3.    Laboratory Equipment  29

3.1.     Shake Tables  29

3.1.1.1.  Physical data of Shake Tables  30

3.1.1.2.  Tables Extensions  31

3.1.1.3.  Performance Data   32

3.1.1.4.  Drawings  33

3.1.2.     Shake table O – 6 dof  36

3.1.2.1.  Physical data   37

3.1.2.2.  Capacity data   37

3.1.2.3.  Drawings  37

3.1.3.     Single degree-of-freedom shake table   39

3.1.3.1.  Physical data   39

3.1.3.2.  Capacity data   39

3.1.3.3.  Drawings  40

3.2.     Reaction walls   40

3.2.1.     Reaction Wall –Test Area 2   40

3.2.1.1.  Physical data   40

3.2.1.2.  Capacity data   41

3.2.1.3.  Drawings  43

3.3.     Strong Floors  45

3.3.1.     Strong Floor O – Test Area 1   45

3.3.1.1.  Physical data   45

3.3.1.2.  Capacity data   45

3.3.1.3.  Drawings  45

3.3.1.4.  Simulation Drawings  45

3.3.2.     Strong Floor – Test Area 2   45

3.3.2.1.  Physical data   45

3.3.2.2.  Capacity data   46

3.3.2.3.  Drawings  47

3.4.     Hydraulic Power Supply Systems  47

3.4.1.     Test Area 1   47

3.4.2.     Test Area 2   48

3.4.2.1.  Layout  48

3.4.2.2.  Pumps  49

3.4.2.3.  Service manifolds (ports)  52

3.4.2.4.  Oil Filtration and Cleanliness  53

3.5.     Loading Systems  53

3.5.1.     Hydraulic actuators  53

3.5.1.1.  Hydraulic cylinders  58

3.5.1.2.  Servo-valves  58

3.5.1.3.  Servo-Controllers  59

3.5.1.4.  Hydraulic Service Manifolds  60

3.5.1.5.  Integration options – actuators, controllers, manifolds  61

3.5.2.     Testing Machines  61

3.5.2.1.  MTS Universal Tension Machine - 150 kip (667kN)  61

3.5.2.2.  MTS Axial-Torsion Machine   62

3.5.2.3.  Generic Large Bearing Testing Machine   62

3.5.2.4.  Generic Small Bearing Testing Machine   63

3.5.2.5.  Tinius-Olsen Universal testing Machine–300 kips (1350kN)  63

3.6.     Other Testing Systems  64

3.6.1.     Geotechnical Laminar Box  64

3.6.1.1.  Geometry   64

3.6.1.2.  Features  66

3.7.     Instrumentation   68

3.7.1.     Sensors  68

3.7.1.1.  Motion   68

3.7.1.1.1.  Displacement  68

3.7.1.1.2.  Acceleration   69

3.7.1.1.3.  Rotation   70

3.7.1.2.  Loading   71

3.7.1.3.  Strain   74

3.7.1.4.  Video   75

3.7.1.5.  Images – Still 76

3.7.2.     Conditioners  77

3.7.3.     Electronic Instruments  78

3.7.3.1.  Oscilloscopes  78

3.7.3.2.  Digital Multimeters and Voltage Standards  78

3.7.4.     Instrumentation frames  79

3.7.5.     Instrumentation Databases  80

3.7.5.1.  Instrumentation calibration   80

3.7.5.1.1.  Lab procedures  80

3.7.5.1.2.  Calibration examples and databases  80

3.8.     Data Acquisition Systems  80

3.8.1.     Pacific Instruments  80

3.8.2.     Optim MegaDac   80

3.8.3.     Krypton K600 Portable CMM System    81

3.8.4.     Dell Workstations – Portable DAQ   83

3.8.5.     Dell PC & Data Translation 12 bit Desktop System    84

3.9.     Networks  84

3.9.1.     Description   84

3.9.2.     Schematics  85

3.9.2.1.  Wired   85

3.9.2.2.  Wireless  85

3.9.3.     Servers  86

3.9.3.1.  NEESpop   87

3.9.3.2.  NEES TPM    87

3.9.3.3.  Webserver & Domain Servers  87

3.9.3.4.  Email Server  87

3.9.4.     Mass Storage   88

3.9.4.1.     Data Archival and Organization    88

3.9.5.     Telepresence   89

3.9.6.     Multipurpose Workstations  90

3.9.7.     Computational Workstations  90

 

3.     Laboratory Equipment

3.1.  Shake Tables

Shake table A and B – 6 DOF

Key elements of the SEESL are the two movable, six degrees-of-freedom, shake tables, which can be rapidly repositioned from directly adjacent to one another to positions up to 100 feet apart. Together, these tables can host specimens of up to 100 metric tons and as long as 120 feet, and subject them to fully in-phase or totally uncorrelated dynamic excitations.

Figure 3.1‑1: Shake Table A with Instrumentation Frame and specimen (w/o table extension)

Figure 3.1‑2: Shake Table B (w/o table extension)

 

3.1.1.1.        Physical data of Shake Tables

 

Each shake table has plan dimensions of 3.6 x 3.6 meter and is made of a welded steel construction with a weight of approximately 8 tons. Each table has a painted top surface.

A Parking Frame System consisting of a welded steel frame with electric actuators raises each table for repositioning within the length of the trench. The carrier capable of raising the table with the (4) horizontal actuators, (2) actuator buttresses, and (4) vertical actuators is attached. A steel beam is used for securing the horizontal actuator buttresses to the table during movement. The carrier rides on polyurethane wheels for ease of positioning and tracks along a center rail embedded in the trench floor being moved with a winch system.

Each shake table is driven by the following hydraulic actuators:

1. Longitudinal (X and Y-axis) hydraulic actuators (quantity = 2 each axis)

MTS Model 244.4 Hydraulic Actuator with a dynamic force rating of 21 metric ton and a dynamic stroke of 300 mm (±150 mm). The actuator assembly includes the following:

a. Hollow single piece rod

b. Model 256.25S servovalve rated at 1000lpm

c. LVDT type stroke transducers

d. Swivel heads and bases

e. Close-coupled pressure and return accumulators

f. Differential pressure cells.

2. Vertical (Z-axis) hydraulic actuator (quantity =4)

MTS Model 206.S Hydraulic Actuator with a dynamic force rating of 25 metric ton and a dynamic stroke of 150 mm (±75 mm). The actuator assembly includes the following:

            a. Hollow single piece rod

b. Model 256.18s servovalve rated at 650lpm

c. LVDT type stroke transducers

d. Swivel heads and bases

e. Close-coupled pressure and return accumulators

f. Differential pressure cells

g. Integral static support with 20 ton capacity (total static support capacity is 20 ton x 4 = 80 ton) will all necessary nitrogen supply and control system.

The Hydraulic Power Supply (HPS) subsystem for both shake tables consists of four MTS Model 506.92 pumps rated at 185gpm (700lpm) at 3,000psi (207 bar) each.

3.1.1.2.        Tables Extensions

There are the two 7 x 7 meter shake table extension platforms available for each of the shake tables. The Platforms are of welded steel construction with a weight of approximately 9.8 tons. The extensions have painted top surface.

 

Figure 3.1.1.2‑1: View of both shake tables with extension platforms in place

 

Figure 3.1.1.2‑2: Shake Table B with extension platform

3.1.1.3.        Performance Data

The two six degrees-of-freedom shake tables are designed for the nominal performance shown in Table 1. These performance data are based continuous uniaxial sinusoidal motion with 20-ton rigid specimen. System performance levels will be reduced with payloads larger than nominal.

 

Table 1: Performance data of six degrees-of-freedom shake tables.

3.1.1.4.          Drawings

Figures 1 to 5 present construction drawings for the six degrees-of-freedom shake tables. Figure 1 presents general plan view of the laboratory floor including the two shake tables in the trench next to a reaction wall. Figure 2, 3 and 4 shows top, bottom, and side views of one of the shake tables, respectively. Figure 5 shows details of the mounting bolts used to anchor a test specimen on the shake tables.

Figure 3.1.1.4‑1: General plan view of laboratory floor

Figure 3.1.1.4‑2: Top view of six degrees-of-freedom shake tables

 

Figure 3.1.1.4‑3: Bottom view of six degrees-of-freedom shake tables

Figure 3.1.1.4‑4: Side view of six degrees-of-freedom shake tables

Figure 3.1.1.4‑5: Mounting bolts details of six degrees-of-freedom shake tables

 

Figure 3.1.1.4‑6: Plan view of table extension

 

Figure 3.1.1.4‑7: Plan view of table extension, Detail 1

3.1.2.   Shake table O – 6 dof

Located in the original SEESL, the 3.66 by 3.66 m shake table has six controlled degrees of freedom (excluding the transverse translational movement). The longitudinal (horizontal), vertical and roll degrees of freedom are programmable with feedback control to simultaneously control displacement, velocity, and acceleration.

 

3.1.2.1.        Physical data

 The five degree-of-freedom shake table has payload capacity of 50 tons and a useful frequency range of 0 to 50 Hz. The table is normally furnished with a reinforced concrete testing platform of 6.1 m by 3.66 m plan dimensions that extends the useful testing area beyond the table's dimensions but limits the payload to 42.5 tons. The testing platform has holes on a one foot square grid for attaching test specimens.

3.1.2.2.        Capacity data

The five degrees-of-freedom shake table is designed for the nominal performance shown in Table 2. These performance data are based continuous uniaxial sinusoidal motion with 20-ton rigid specimen. System performance levels will be reduced with payloads larger than nominal.

 

Table 2 : Performance data of five degrees-of-freedom shake tables

3.1.2.3.        Drawings

Figure 3.1.2.3‑1 represents a perspective view of the five degrees-of-freedom shake table and foundation Figure 3.1.2.3‑2 presents a top view of the testing platform of the five degrees-of-freedom shake table. Figure 3.1.2.3‑3 presents a photograph of the five degrees-of-freedom shake table with a test specimen installed on it.

 

Figure 3.1.2.3‑1: Five degrees-of-freedom shake table and foundation

Figure 3.1.2.3‑2: Top view of testing platform of five degrees-of-freedom shake table

 

 

Figure 3.1.2.3‑3: Photograph of five degrees-of-freedom shake table with specimen

3.1.3.   Single degree-of-freedom shake table

The SEESL also hosts a smaller (0.91m x 1.52m) single degree-of-freedom (horizontal) shake table that has a payload capacity of at least 3 tons. The specimen height for the single degree-of-freedom shake table is restricted by uplift conditions since the table rides on slide bearings. The single degree-of-freedom shake table is suitable for use with an available three-story, 3 tons steel model structure.

3.1.3.1.        Physical data

The single degree-of-freedom shake table is driven by a 25kN actuator equipped with two 15gpm (56.78lpm) servovalves.

3.1.3.2.        Capacity data

The single degree-of-freedom shake table is designed for the nominal performance shown in Table 3. These performance data are based continuous uniaxial sinusoidal motion with a 3 ton rigid specimen. System performance levels will be reduced with payloads larger than nominal.

 

Table 3: Performance data of single degree-of-freedom shake tables

 

3.1.3.3.        Drawings

Figure 3.1.3.3‑1: Photograph of single degree-of-freedom shake table with dedicated 3-ton specimen

3.2. Reaction walls

3.2.1.   Reaction Wall –Test Area 2

Reaction Walls and Strong Floors allow 2 for testing of structual components such as steel trusses and concrete slabs.

3.2.1.1.        Physical data

Reaction Wall next to Strong Floor:

·         Length: 41'-0''

·         Height: 30'-0'’

·         Thickness: 2'-0''

 

Reaction Wall next to Shake Table Trench:

·         Length: 23'-0''

·         Height: 30'-0''

·         Thickness: 2'-0''

 

3.2.1.2.        Capacity data

 

Table 4: Strong Wall Capacity Data

3.2.1.3.        Drawings

 

Figure 3.2.1.3‑1: Reaction Wall next to Shake Table Trench

 

Figure 3.2.1.3‑2: Reaction Wall next to Shake Table Trench

Figure 3.2.1.3‑3: Plan view of Reaction Walls in Testing Area 2

Figure 3.2.1.3‑4: Cross-section of Reaction Walls in Testing Area 2

3.3. Strong Floors

3.3.1.   Strong Floor O – Test Area 1

3.3.1.1.        Physical data

The test floor is a five cell reinforced concrete box girder 40 ft. (12.2m) long, 60 ft. (18.3m) wide, and 8 ft. (2.5m) overall in height. The thickness of the top test floor slab is 18 in. (46 cm). Tie down points consist of (4) 2 ½" holes which are arranged symmetrically in both directions.

3.3.1.2.        Capacity data

Each tie down point has an axial load allowable capacity of 250 kips (1112kN). Figure 2 presents a view of the strong floor including the layout of the tie down points.

3.3.1.3.        Drawings

 

Figure 3.3.1.3‑1: Strong Floor in Testing Area 1

 

3.3.1.4.        Simulation Drawings

3.3.2.   Strong Floor – Test Area 2

3.3.2.1.        Physical data

The test floor is a reinforced concrete box girder 79 ft. (24m) long, 39 ft. (11.8 m) wide. The thickness of the top test floor slab is 24 in. (60 cm).

 

 

 

 

3.3.2.2.        Capacity data

Table 5: Strong Floor Capacity Data

3.3.2.3.        Drawings

Figure 3.3.2.3‑1: Plan view of Strong Floor in Testing Area 2

 

 

Figure 3.3.2.3‑2: Cross-section view of Strong Floor in Testing Area 2

3.4. Hydraulic Power Supply Systems

3.4.1.   Test Area 1

Table 6: Flow Rate Data of HPS in Testing Area 1

Device Type	Quantity	Flow Rate (per unit) gpm [lpm]	Equipment Designation
MTS506.81 HPS	2	140* [1245.5]	Non-NEES
MTS Manifold 290 Series	3	50 [189]	Non-NEES
MTS Manifold 290 Series	2	100 [378.54]	Non-NEES
MTS Manifold 290 Series	1	250[946.35]	Non-NEES

* Flow Rate available in increments of 70 gpm (265 lpm)

 

3.4.2.   Test Area 2

3.4.2.1.        Layout

The pump room, located in the basement of the Ketter Hall NEES lab addition, houses four MTS 506.92 Hydraulic Power Supply (HPS) units, each rated at 185gpm (700lpm) flow with 3,000psi (207 bar) working pressure. Each HPS consists of two high-pressure, variable volume main pumps and a low pressure “supercharge” pump that draws oil from the reservoir and supplies a constant oil pressure and flow to the inlets of the main pumps. These units have oversized reservoirs to accommodate the additional accumulator oil volume required for high performance dynamic testing. Hydraulic system oil is cooled by pumping hydraulic fluid through a system of heat exchangers (one located on each HPS) that are connected to the campus chilled water system. The chilled water is supplied at an average year-round temperature of 50 deg. F. Temperature-sensitive flow control valves are provided by MTS as part of the HPS assembly. These valves regulate the flow of chilled water through the heat exchangers as a function of hydraulic fluid system temperature. The hydraulic fluid is maintained at an optimum working temperature of 100 – 110 deg F.

 

Figure 3.4.2.1‑1: MTS 506.92 Hydraulic Power Supply

3.4.2.2.        Pumps

The laboratory hydraulic distribution system is an integrated solution for the combined functions of seismic and structural testing.  The system was designed to minimize system expenditure (by reducing the use of duplication) and to maximize performance and capabilities.

The pump room piping segment is connected to the outputs of the four HPS units and runs directly to the through an opening in the table trench wall. The diameter of the common piping in the HPS room area is 130 mm pressure and 220 mm return line with 2 inch drain lines. The reservoirs of the HPS units are connected together with large diameter piping to provide a common reservoir from which all 8 pumps on the 4 HPS units can draw oil.

The seismic piping system runs along the length of the shake table trench. This piping is sized to allow both the seismic table and structural actuators to run simultaneously for hybrid testing applications with table-mounted specimens coupled with the strong wall at the east end of the trench. Hydraulic outlets with manual valves are located along the trench for positioning of the movable tables, offering maximum flexibility. Outlets are also located along the strong wall for connecting the Hydraulic Service Manifolds for the high flow structural actuators. Flexible hoses are used to connect the table system and the structural actuators to the main hard line distribution outlets.

Four hydraulic outlet stations are located along the table trench for connection of hoses. Two stations are used to connect to the moveable tables at any one time and any free stations can be used to allow connection of structural actuators to the strong floor along the north side of the floor for certain configurations. By design, one trench distribution manifold station will allow one table to be positioned to any one of four locations without breaking hose connections. This helps simplify repositioning of the table system.

The main branch line running from the HPS piping manifold in the table trench area to the east end of the trench is sized to provide in excess of 1200 GPM pressure and 1600 GPM return (average) of oil flow using 150 mm pressure piping and 220 mm return piping with 2 inch drain lines. Wall openings are cast into the concrete structure of the basement and the table trench, through which the hard line is routed.

Over 700 gallons of oil volume accumulation (Figure 3.4.2.2‑1) is provided through four distributed accumulation bank systems. These accumulators are located in the basement below the strong floor adjacent to the high flow hydraulic distribution manifolds (see figure x). These are engineered to operate in a horizontal manner to provide maximum accessibility for maintenance in the basement.

Figure 3.4.2.2‑1 MTS Accumulator System (Qty: 4)

Figure 3.4.2.2‑2 Hydraulic Distribution System

 

At the end run of the main branch line, a secondary piping distribution runs south below the strong floor along the strong wall to service the structural testing area. This secondary branch line for structural testing also consists of 150 mm pressure piping and 220 mm return line piping with 2 inch drain lines along the length of the strong wall. Line accumulation from the individual Hydraulic Service Manifolds and the basement accumulation banks supplements the flow above the 800 GPM output from the HPS units as needed. Vertical risers run from the basement level through the strong floor to the four distribution manifolds mentioned earlier. The pressure risers are 130 mm and the return risers 140 mm in diameter. Strong floor cut outs (precast in the floor) allow the passage of the piping system from the basement to the top of the strong floor.

 

At the strong floor surface, adjacent to the strong wall, four high flow manual distribution manifolds (Error! Reference source not found.) are located, with four sets of 2 inch hand and check valves to allow connection to the three moveable Hydraulic Service Manifolds. This arrangement will supply the highest available volume flow to the structural actuators for their demanding applications for real time hybrid and other high-demand testing. These high flow manual distribution manifolds can also be used as general purpose distribution manifolds to connect other actuators for more traditional structural testing applications (when the high flow structural actuators are not in use) adding setup flexibility along the strong wall area.

 

Figure 3.4.2.2‑3: MTS High Flow Hydraulic Distribution Manifold

 

Beginning at the fourth high flow structural testing distribution manifold location, approximately 60 feet of 75 mm diameter piping runs below the strong floor along the south edge of the floor. Three low flow distribution manifolds (Error! Reference source not found.) are evenly spaced along this piping run and each is provided with two sets of hand and check valves on the testing floor level. The vertical risers consist of 2 inch SST piping (pressure and return) to each distribution manifold.

Figure 3.4.2.2‑4: MTS Low Flow Hydraulic Distribution Manifold

 

When considered as a single system, the hard line runs and outlet stations in the table trench, and the hard line runs and manifolds along the strong wall and south strong floor allow hydraulic power to be distributed to three sides of the strong floor area. This distribution scheme allows hydraulic power coverage over the majority of the strong floor area.

3.4.2.3.        Service manifolds (ports)

Three high flow (800gpm) Hydraulic Service Manifolds with additional accumulation are typically located near the lab reaction wall to provide full flow capacity to the high speed structural actuators. For structural testing applications, these Hydraulic Service Manifolds are used for on/off control with 40 gallons each of pressure and return accumulator banks. These service manifolds each support a single actuator assembly with an 800 GPM servo valve. These Hydraulic Service Manifolds can be positioned throughout the testing Laboratory, with high speed testing typically performed at the lab reaction wall where the distribution piping and accumulator systems will maximize the flow capabilities. They can also be positioned at any free station located at the seismic table trench area if needed.

Figure 3.4.2.3‑1: MTS 800 GPM Hydraulic Service Manifold

 

Each table system has a dedicated integral Hydraulic Service Manifold with 30 gallons each of pressure and return accumulators.

Two (2) 50gpm hydraulic service manifold are available for connecting the static actuators. Typically these manifolds are connected to the south strong floor distribution manifolds; however they can be used throughout the laboratory wherever a connection point exists.

 

Figure 3.4.2.3‑2: MTS 293.12 50 GPM Hydraulic Service Manifold

 

 

3.4.2.4.        Oil Filtration and Cleanliness

The hydraulic distribution system is designed to meet an oil filtration quality of ISO 13/10. This level of cleanliness is critical for high fidelity servo valve systems. The system is designed to use Mobil DTE 25 hydraulic fluid or the equivalent. Oil samples are taken at 3 month intervals and sent to MTS for evaluation. If particle counts exceed the ISO 13/10 specification, corrective action is immediately taken. This typically involves flushing the hydraulic distribution system at high flow rates for several hours or days, after which oil samples are again drawn for evaluation.

 

3.5. Loading Systems

3.5.1.   Hydraulic actuators

The laboratories feature numerous actuators suitable for a variety of different testing procedures. A detailed listing of the different actuators is presented in table 1 in the lab manual.

MTS Systems Corporation servo-controlled static rated actuator (x2) with a load capacity of 440 kips (1962 kN) and an available stroke of 40 in. The actuator's servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 0.393 in./sec (9.982 mm/sec) with that particular valve.

Miller servo-controlled static rated actuators (x2) with a load capacity of 250 kips (1112.06 kN) and an available stroke of 8 in. (203.2 mm). The actuator's servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 0.65 in./sec (16.5 mm/sec) with that particular valve. Force is measured using manufacture supplied load cells and displacement is measured using internally mounted LVDTs.

MTS Systems Corporation servo-controlled dynamic rated actuator (x3) with a load capacity of 220 kips (978.61 kN) and an available stroke of 40 in.. The actuator's servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 0.75 in./sec (19.1 mm/sec) with that particular valve. This particular actuator is equipped with an alternate servovalve for high speed testing which has a flow rate of 800 gpm (3000 lpm), and the actuator has a maximum velocity of 42in./sec (1066.8 mm/sec). Force is measured using a manufacture supplied load cell and displacement is measured using internally mounted LVDTs.

MTS Systems Corporation servo-controlled dynamic rated actuator (x1) with a load capacity of 220 kips (978.61 kN) and an available stroke of 10 in. (254.0 mm). The actuator's servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 0.75 in./sec (19.1 mm/sec) with that particular valve. This particular actuator is equipped with an alternate servovalve for high speed testing which has a flow rate of 250 gpm (946.35 lpm), and the actuator has a maximum velocity of 12.5 in./sec (317.5 mm/sec). Force is measured using a manufacture supplied load cell and displacement is measured using internally mounted LVDTs.

MTS Systems Corporation servo-controlled dynamic rated actuator (x1) with a load capacity of 110 kips (489.30 kN) and an available stroke of 10 in. (254.0 mm). The actuator's servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 1.5 in./sec (38.1 mm/sec) with that particular valve. This particular actuator is equipped with an alternate servovalve for high speed testing which has a flow rate of 250 gpm (946.35 lpm), and the actuator has a maximum velocity of 25 in./sec (635.0 mm/sec). Force is measured using a manufacture supplied load cell and displacements is determined using internally mounted LVDTs.

Parker servo-controlled static rated actuators (x4) with a load capacity of 70 kips (311.38 kN) and an available stroke of 4 in. (101.60 mm). The actuator's servovalves have flow rates of 15 gpm (56.78 lpm), and the actuators have a maximum velocity of 2.4 in./sec (60.96 mm/sec) with that particular valve. Due to the fact that the actuators are single-ended, they are primarily used for vertical load application. Force is measured using in-house custom built load cells and displacement is measured using external displacement transducers.

MTS Systems Corporation servo-controlled dynamic rated actuator (x1) with a load capacity of 55 kips (244.65 kN) and an available stroke of 12 in. (304.8 mm). The actuator's servovalve has a flow rate of 90 gpm (340.69 lpm), and the actuator has a maximum velocity of 17 in./sec (431.8 mm/sec) with that particular valve. Force is measured using a manufacture supplied load cell and displacement is measured using internally mounted LVDTs.

MTS Systems Corporation servo-controlled dynamic rated actuator (x1) with a load capacity of 55 kips (244.65 kN) and an available stroke of 24 in. (609.6 mm). The actuator's servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 2.95 in./sec (74.9 mm/sec) with that particular valve. Force is measured using a manufacture supplied load cell and displacement is measured using internally mounted LVDTs.

MTS Systems Corporation servo-controlled dynamic rated actuator (x1) with a load capacity of 22 kips (97.86 kN) and an available stroke of 6 in. (152.4 mm). The actuator's servovalve has a flow rate of 10 gpm (37.85 lpm), and the actuator has a maximum velocity of 5 in./sec (127.0 mm/sec) with that particular valve. Force is measured using an in-house custom built load cell and displacement is measured using internally mounted LVDTs

MTS Systems Corporation servo-controlled dynamic rated actuators (x2) with load capacities of 5.5 kips (24.47 kN) and an available stroke of 6 in. (152.4 mm). One actuators servovalve has a flow rate of 30 gpm (113.56 lpm), and the actuator has a maximum velocity of 50 in./sec (1270.0 mm/sec) with that particular valve. The other actuators servovalve has a flow rate of 15 gpm (56.78 lpm), and the actuator has a maximum velocity of 27 in./sec (685.8 mm/sec) with that particular valve. Force is measured using in-house custom built load cells and displacement is measured using internally mounted LVDTs.

MTS Systems Corporation servo-controlled dynamic rated actuator (x1) with a load capacity of 2.2 kips (9.79 kN) and an available stroke of 4 in. (101.6 mm). The actuators servovalve has a flow rate of 10 gpm (37.85 lpm), and the actuator has a maximum velocity of 49 in./sec (1244.6 mm/sec) with that particular valve. Force is measured using a manufacture supplied load cell and displacement is measured using internally mounted LVDTs.

Figure 3.5.1‑1: Static Actuators MTS 243.90T

 

Figure 3.5.1‑2: Dynamic Actuators MTS 244.51S

 

Table 7: Performance Data of Actuators

* Velocity assumes no load on actuator
** Same as previously listed actuator with different servovalve
*** Fees will not be applied to scheduled NEES projects. Fees wil be charged for extra unscheduled time. Disclaimer: The rates are direct costs only and DO NOT include a 57% Department fee for administration and university fees. This overhead has to be added in estimates.
**** MTS 256.80S servovalve be controlled with MTS 469D controller ONLY

 

3.5.1.1.        Hydraulic cylinders

3.5.1.2.        Servo-valves

Table 8: Performance data of Servo-valves

* Permanent Servovalve for seismic simulator
** Fees are for servovalve substitutions only. Fees will not be applied to scheduled NEES projects. Fees wil be charged for extra unscheduled time. Disclaimer: The rates are direct costs only and DO NOT include a 57% Department fee for administration and university fees. This overhead has to be added in estimates.

3.5.1.3.        Servo-Controllers

MTS 433 Servo-Controllers

These controllers consist of rack mounted card cages (one cage for each controlled channel). Each cage contains modular circuit cards for program input to the actuator, command vs. feedback comparison, load cell conditioning, strain gage bridge completion and conditioning, LVDT conditioning, and program error and limit detection. Due to the size and relative immobility of these controllers, they are dedicated to each of the two MTS Hydraulic Testing Machines (see table 5). While not technically part of the servo controller, a multi-waveform function generator is integral to each of the racks these controllers are mounted in.

A subset of modified MTS 433 controllers (labeled as MTS 469 controllers) is incorporated into the control system for the lab's seismic simulator. This control system provides acceleration, velocity and displacement control for the five active degrees of freedom in which the table is capable of moving. Provisions are also made for cross-coupling control to minimize the error encountered during the testing of tall and/or heavy structures.

MTS 406 Servo-Controllers

These controllers consist of portable, table top boxes which contain a main circuit board that provides program input to the actuator, command vs. feedback comparison, error/limit detection and LVDT conditioning. Plug-in cards provide load cell conditioning, third stage valve control, and other custom features as required per application. The portability of these controllers enables them to be moved and reconfigured easily and interfaced with a variety of actuators.

MTS 458 Servo Controllers

These are hybrid controllers, consisting of analog and digital technology. They can be configured as either rack mounted or free standing. They consist of a card cage with a fixed hydraulic manifold control module, and interchangeable actuator controllers. These controllers are highly configurable, providing servo control error, limit detection and signal conditioning on each card. Typically, a 458 AC Controller module is configured as the master controller, with an actuator AC LVDT as the feedback device. DC controllers for load and strain feedback (or other AC controllers) are slaved to the master controller, and switching between control modes (displacement, force, strain) is accomplished with a series of push buttons and digital readouts of the controlled variables. Generally speaking, these controllers are dedicated to specific actuators or testing machines, although they can be reconfigured with relative ease.

 

Table 9: Performance Data of Servo-Controllers

* Dedicated controller for MTS 150 kip Tension Machine
** Dedicated controller for MTS Axial / Torsion Testing Machine
*** Dedicated controllers for MTS/SUNY Seismic Simulator
**** Fees will not be applied to scheduled NEES projects. Fees wil be charged for extra unscheduled time. Servo controller substitution is availible for one time fee of $1200. Disclaimer: The rates are direct costs only and DO NOT include a 57% Department fee for administration and university fees. This overhead has to be added in estimates.

3.5.1.4.        Hydraulic Service Manifolds

Hydraulic Service Manifold (HSM) is a hydraulic pressure and flow regulation device that controls pressure to a single test station from the main hydraulic power unit (HPU).

 

Table 10: Performance Data of Hydraulic Service manifolds

Flow Rate available in increments of 70 gpm (265 lpm) , ** Flow Rate available in increments of 90 gpm (340 lpm)

3.5.1.5.        Integration options – actuators, controllers, manifolds

It is important to understand that the laboratory is not restricted to the specifications of each particular hydraulic actuator. In an actual experiment a hydraulic actuator system is composed of three major components including the hydraulic cylinder, servovalve, and servo-controller. Due to the fact that the majority of the equipment used in the laboratories is manufactured by MTS Systems, the components of each actuator can be interchanged. Different servovalves can be used on the same hydraulic cylinder to produce low and high speed velocities. This in turn may change the rating of the hydraulic actuator from static to dynamic and vice versa.

Moreover, different servo-controllers may be used depending on the desired experimental set up. For example, an experiment may entail applying a force to a horizontal beam and at the same time ensuring that the beam is kept horizontal. This would require an initial actuator to apply force to the system as well as a second actuator to ensure that the position of the beam is correct. Different servo-controllers can be used that will allow the system to obtain actual feedback from the two actuators so that any necessary corrections can be made immediately. Refer to Table 2 for a complete list of the available servo controllers.

3.5.2.   Testing Machines

3.5.2.1.          MTS Universal Tension Machine - 150 kip (667kN)

This is a low speed machine capable of tension or compression testing of specimens or components composed of steel, concrete, rubber or other materials. The force range is adjustable to calibrated ranges of 200, 100, 40, and 20 kips, and the displacement range is adjustable to ± 4, 2, 1, and .5 in. for applications where greater sensitivity is required. The machine can be controlled in either force or displacement mode

Figure 3.5.2.1‑1: MTS Universal Tension Machine

3.5.2.2.           MTS Axial-Torsion Machine

This machine is capable of biaxial testing of specimens and components of many sizes, up to 4 ft. (1.22 m) in length. Control modes available are force, strain and displacement in axial mode, and torque (in/lb.), strain and rotation (degrees) in torsion mode. The machine has calibrated ranges of 100, 50, 20, and 10 kips, and ± 5, 2.5, 1, and .5 in. axially, as well as 50000, 25000, 10000, and 5000 inch-pounds, and 50, 25, 10, and 5 degrees in the torsion mode.

Figure 3.5.2.2‑1: MTS Axial-Torsion Machine

3.5.2.3.        Generic Large Bearing Testing Machine

This machine has been developed for the testing of sliding bearings. It is capable of 1600 (7117.2kN) kips compression (expandable to 2200 kips / 9786.1kN), lateral load of up to 220 kips (978.6kN), stroke of ± 5 in. (12.7 cm) and velocities of up to 10 in./sec (254 mm/sec). Bearing plan dimensions can be up to 45 in. (114.3 cm) by 45 in. (114.3 cm). It can be used for the seismic testing of sliding bearings and the characterization of frictional properties of large-dimension material interfaces. The machine can also be used for the testing of elastomeric bearings. The machine is capable of testing pairs of bearings, or a single bearing with the use of rolling cylinders. Figure 9 presents a view of this testing machine.

Figure 3.5.2.3‑1: Large Bearing Testing Machine

3.5.2.4.          Generic Small Bearing Testing Machine

This machine has been developed for the testing of single bearings under controlled conditions of vertical load, lateral movement and rotational movement. It has a 140 kip (622.8kN) vertical load capacity, 55 kip (244.7 kN) horizontal load capacity, ± 6 in. (15.24 cm) horizontal movement capacity with up to 15 in./sec (381 mm/sec) velocity, and rotational capability of ± 2 degrees. Reaction forces can be directly measured by a multi-component load cell which currently has a rated capacity of 20 kips (89 kN) shear and 50 kips (222.4 kN) axial load. The machine can been used in the testing of elastomeric and sliding bearings, including tests under variable axial load and tests of bearings pre-stressed by tendons to prevent uplift. Figure 10 presents a view of the testing machine during testing of an elastomeric bearing.

Figure 3.5.2.4‑1: Small Bearing Testing Machine

3.5.2.5.        Tinius-Olsen Universal testing Machine–300 kips (1350kN)

This machine has been used primarily for testing concrete cylinders, structural steel members, and standard steel test specimens. The machine consists of a dual crosshead, mechanical screw load frame, with a test surface platen having an effective area of 31 in. (79 cm) x 43 in. (109 cm). The platen is 45 in. (114.3) from the lab floor. The crossheads can be placed at any height along the screws to allow testing of specimens up to 72 in. (183 cm) long in tension. The upper crosshead is locked in place during testing, while the lower crosshead moves along the machine's screws to apply tension or compression to the specimen. Compression testing capacity is limited by the tendency of tall specimens to buckle, but theoretically a 72 in.(183 cm) specimen can also be tested in compression. The machine is capable of testing specimens in tension or compression to 300 kips (1334kN). Force readout is provided by a dial indicator calibrated in ranges of 3, 12, 60 and 300 kips (13. 53, 267, and 1334kN). For electronic readout, any suitable load cell can be mounted in series with the test specimen. Alternatively, a Temposonic displacement transducer is mounted on the gear rack assembly which drives the dial indicator, providing a linear voltage readout proportional to the position (force readout) of the dial indicator. Displacement readout is accomplished by using displacement transducers of suitable range mounted parallel to (or directly on) the test specimen.

Figure 3.5.2.5‑1: Tinius-Olsen Universal Testing Machine

3.6. Other Testing Systems

3.6.1.   Geotechnical Laminar Box

3.6.1.1.        Geometry

The UB Full-scale prototype 1-g soil and soil-structure interaction testing facility consists of a 2-D modular laminar box (Module A1: 2.75x5x6.2m, internal dimensions). The 2-D laminar box is made of 24 laminates, separated and supported by ball bearings, facilitating 2-D motions, including ability to simulate sloping ground subjected to large deformations. The box can simulate boundary stresses closely to that of a free ground. The laminar box can also be reconfigured into two other configurations or modules (module B1: two boxes 2.75x2.5x3.1m each or module B2: 2.75x2.5x6.2m) or at a reduced height. The box can allow up to 15% shear strain in general, larger deformations for selected cases of loadings, and large permanent deformations on a case-by-case basis, subject to safety and other limitations. Figures 3.6.1.1-1-3 present schematic diagrams of the laminar box modules. Figure 3.6.1.1‑4 shows a picture of the laminar box.

                               

(a) Module B1: 2.75x 2.5x3.1 m       (b) Module B2: 2.75x 2.5x6.2 m        (c) Module A1: 2.75x5x6.2m           (d) 2-D Bearing

(e) Module A2: 2.75x5x3.2 m (not shown)

Figure 3.6.1.1‑1:  2D Laminar Box Modules at SEESL

Figure 3.6.1.1‑2: Laminar Box (1-g Full scale Tests) on the Strong Floor

 

Figure 3.6.1.1‑3: A typical pile test configuration

 

Figure 3.6.1.1‑4: Laminar Box in Test Area 2

 

3.6.1.2.        Features

Table 11: Laminar Box Module Dimensions & Details

 

Table 11 presents the dimensions and details of the various modules. The load capacity characteristics are to be considered preliminary, subject to verification and update. In its largest configuration (Module A1: 2.75x5x6.2m), the laminar box is supported on the strong floor, on a steel shaking base frame supported on rubber/sliding bearings. It can be actuated in 1-D using one or more of the UB-NEES 100 ton fast dynamic actuators (MTS), or in 2-D by using two or more 100 tons fast actuators mounted at 45 degrees on the new UB-NEES reaction wall (30ft high, 41ft wide). The total weight of the box filled with sand is about 150-170 tons, whereas the maximum horizontal dynamic actuator capacity is 90 tons in each horizontal direction simultaneously or 180 tons in any one direction. Thus very large shaking g levels are possible. The actuators can be fed with any recorded motion and the controllers can be set to compensate for any compliance effects to accurately shake the base of the soil to meet any desired recorded earthquake motion. Data acquisition systems are available to monitor up to 256 channels at high frequencies. High resolution imaging tools can be positioned to capture deformation patterns at any selected zone in the soil box.

In its smaller configurations (modules A2, B1 and B2), the laminar box may be mounted on a shake table with a maximum payload capacity of 50 tons weight including the box weight. Where higher weights are expected the box may be assembled over a steel base frame supported by two identical shake tables allowing up to 100 tons maximum weight, including the weight of the box and the steel base frame. The shake table payload-acceleration characteristics are presented elsewhere. Typically each shake table can operate at up to 1.15g at a nominal payload weight of 20 tons, and the acceleration decreases with an increase in payload weight. The shake tables have 6 degrees of freedom, but the 1-g soil tests are limited to 1-D or 2-D at this time.

Sand may placed inside the box by air pluviation, wet pluviation, or hydraulic filling. Due to dust control considerations the hydraulic filling method is preferred. A close-loop system has been developed to pump sand-slurry using sand-slurry pump from sand containers located just outside the Test Area 2 building. In the case of dry pluviation, soil saturation may be achieved by percolating by CO₂ through the soil and seeping water with the aid of vacuum suction.

The facility also has capability to simulate the inertial effects of the building/bridge pier etc. on the foundation/pile cap via mass-spring system and/or hybrid system where the loads/moments from the building/bridge pier can be applied via fast actuators mounted on the reaction wall. The soil experiments also can be coupled with other physical experiments at UB or elsewhere and/or computational models that simulate the response of the system or structure supported on the soil.

 

3.7. Instrumentation

3.7.1.   Sensors

3.7.1.1.        Motion

3.7.1.1.1. Displacement

The laboratory uses many different types of displacement transducers that each have various attributes and limitations which determine their suitability for different applications. The following is a list of each different displacement transducer and a brief summary of its mechanics.

Linear Potentiometers

The most readily available and simplest position transducer is a linear potentiometer excited by a DC source such as a battery. It may be hooked up to deliver an output voltage that is essentially proportional to a straight-line position varying between zero and a maximum. Alternatively, a potentiometer may be hooked up to deliver an output varying between a negative and positive voltage in proportion to a mechanical displacement that also varies between a maximum negative and a maximum positive value relative to a defined null position.

Linear Variable Differential Transformer (LVDT)

The word "linear" appears in the name of the LVDT to denote straight-line motion as opposed to a linear relationship between input and output. Three coils of electrically conducting wire are wound on an insulating form. By the principle of mutual inductance an AC voltage across the terminals of the primary coil induces a voltage of the same frequency in each of the two secondary coils. If the moveable ferromagnetic core is centered, the two secondary voltages are of the same amplitude. For a positive displacement of the core, the voltage appearing across the number 1 secondary coil is greater in amplitude than at the null condition, while the amplitude across the number 2 secondary coil is less.

MTS Temposonic Displacement Transducer

Initially a current pulse is applied to the conductor within the waveguide over its entire length. There is another magnetic field generated by the permanent magnet that exists only where the magnet is located. This field has a longitudinal component. These two fields join vectorially to form a helical field near the magnet which in turn causes the waveguide to experience a minute torsional strain or twist only at the location of the magnet. This torsional strain pulses propagates along the waveguide at the speed of sound in this material. When this torsional pulse arrives at the tapes in the head it is converted into a dynamic longitudinal pulse injected into the tapes. The longitudinal pulses cause the tapes to experience a momentary change in reluctance. Two coils coupling these tapes mounted in the field of two bias magnets will generate a momentary electrical pulse caused by the change in reluctance in the tapes. In order to extract the useful position information we measure the time between when we launch the initial current pulse and the time we receive the signal from the output coils. This time is a very precise function of the position of the moving magnet.

Figure 3.7.1.1.1‑1: Temposonic 1 Dimension Drawing

3.7.1.1.2. Acceleration

Piezoresistive Accelerometer

This type of accelerometer, also known as a strain gage accelerometer, is similar in principle to a piezoelectric accelerometer except it is equipped with a built in resistor, which allows it to be used with a standard signal conditioner.

Table 7 presents a summary of the available transducers (excluding load cells) and their range of measurement.

Table 12: Available Transducers

* Fees will not be applied to scheduled NEES projects. Fees will be charged for extra unscheduled time. Disclaimer: The rates are direct costs only and DO NOT include a

3.7.1.1.3. Rotation

The laboratory uses rotational transducers that also have various attributes and limitations which determine their suitability for different applications. The following is a brief summary of its mechanics.

Rotary Variable Differential Transformer (RVDT)

RVDTs incorporate a proprietary noncontact design that dramatically improves long term reliability when compared to other traditional rotary devices such as syncros, resolvers and potentiometers. This unique design eliminates assemblies that degrade over time, such as slip rings, rotor windings, contact brushes and wipers, without sacrificing accuracy.

High reliability and performance are achieved through the use of a specially shaped rotor and wound coil that together simulates the linear displacement of a Linear Variable Differential Transformer (LVDT). Rotational movement of the rotor shaft results in a linear output signal that shifts ±60 (120 total) degrees around a factory preset null position. The phase of this output signal indicates the direction of displacement from the null point. Noncontact electromagnetic coupling of the rotor provides infinite resolution, thus enabling absolute measurements to a fraction of a degree.

Although capable of continuous rotation, most RVDTs are calibrated over a range of ±30 degrees, with nominal nonlinearity of less than ±0.25% of full scale (FS). Extended range operation up to a maximum of ±90 degrees is possible with compromised linearity.

R30D

The R30D RVDT is a DC operated noncontacting rotary transducer. Integrated signal conditioning enables the R30D to operate from a bipolar ±15 VDC source with a high level DC output that is proportional to the full range of the device. Calibrated for operation to ±30 degrees, the R30D provides a constant scale factor of 125 mVDC/degree. Nonlinearity error of less than ±0.25% FS is achieved while maintaining superior thermal performance over -18°C to 75°C.

3.7.1.2.        Loading

Load Cells

Due to the fact that many of the test apparatuses are specifically developed for single experiments, in-house custom built load cells are often used. The geometric layout of a typical load cell is shown in Figure 11. They are fabricated from a thick wall cylindrical steel tube. The turned down wall thickness, height, and radius are determined based on the expected maximum stresses in the load cells during testing.

Figure 3.7.1.2‑1: Geometric Layout of Typical Load Cell

 

The attachment plates ensure a uniform stress distribution over the entire load cell and provide anchorage into the columns. In the most complicated custom built load cells, axial, shear, and moment stresses can be measured from Wheatstone bridge circuits wired according to Figure 12. Simpler compression-tension load cells are also commonly built using only an axial Wheatstone bridge circuit.
In addition a majority of the MTS, Miller, and Parker Actuators were purchased with a load cell provided by the manufacturer. These load cells are often used in experimentation.

For more detail on our 6” Five-Component Load Cell in-house made Load Cells please refer to this document:

            Load Cells Drawings and Calibrations

 

Delta P Cells

Delta P cells are used on many of the actuators available in the laboratories. The MTS servo controllers utilize the Delta P (differential pressure) measured across the actuator piston as a stabilizing variable during the control of an actuator's motion.

Table 6 lists the different available load measuring devices.

 

 

 

Table 13 : Available Load Measuring Devices

Load Units Kips[kN], Moment Units Kips-Inch [kN-m]

Figure 3.7.1.2‑2: Typical Strain Gage Positioning and Wiring for Multidirectional Load Cells

 

 

3.7.1.3.        Strain

The Strain Gauge

While there are several methods of measuring strain, the most common is with a strain gauge, a device whose electrical resistance varies in proportion to the amount of strain in the device. The most widely used gauge is the bonded metallic strain gauge.

The metallic strain gauge consists of a very fine wire or, more commonly, metallic foil arranged in a grid pattern. The grid pattern maximizes the amount of metallic wire or foil subject to strain in the parallel direction (Figure 3.7.1.3-1). The cross sectional area of the grid is minimized to reduce the effect of shear strain and Poisson Strain. The grid is bonded to a thin backing, called the carrier, which is attached directly to the test specimen. Therefore, the strain experienced by the test specimen is transferred directly to the strain gauge, which responds with a linear change in electrical resistance. Strain gauges are available commercially with nominal resistance values from 30 to 3000 Ω, with 120, 350, and 1000 Ω being the most common values.

 

Figure 3.7.1.3-1: Bonded Metallic Strain Gauge

 

It is very important that the strain gauge be properly mounted onto the test specimen so that the strain is accurately transferred from the test specimen, though the adhesive and strain gauge backing, to the foil itself. A fundamental parameter of the strain gauge is its sensitivity to strain, expressed quantitatively as the gauge factor (GF). Gauge factor is defined as the ratio of fractional change in electrical resistance to the fractional change in length (strain):

The Gauge Factor for metallic strain gauges is typically around 2.

 

Table 14: Available strain gauges

 

 

3.7.1.4.        Video

For video recording of experiments, lab is equipped with three HD (High Definition) camcorder, 12 PTZ cameras and 10 CCD cameras with integrated microphones.

HD camcorder is JVC DIGITAL HD CAMCORDER JY-HD10U that has following features:

·         High Definition Recording Capability:

o        720/30P (MPEG2)

o        480/60P (MPEG2)

·         High Definition Playback Capability:

o        1080/60i

o        720/60P

o        480/60isn

o        480/60i 4:3

·         Standard definition Recording/Playback

·         480/60i 4:3 Recording on Standard Mini DV Tape

·         Lens for HD video image x10, F1.8

·         Optical image stabilizer system: with on/off switch

·         1/3-inch 1.18 Mega-pixel progressive scan CCD (Single chip)

·         16:9 still image capture, MPEG-4 clip capture with SD memory card

·         Real time video streaming possible via USB interface to PC

Figure 3.7.1.4‑1: JY-HD10U Camera

 

12 PTZ cameras are  4 Canon VC-C4R Cameras and 8 Canon VC-C4 Cameras.

 

Table 15: Canon VC-C4/VC-C4R Camera Specification

 

Figure 3.7.1.4‑2: Canon VC-C4 and VC-C4R Cameras

 

10 CCD cameras are VC-806b-audio models with following features:

·         Audio: AUDIO MAX 2Vp-p 50 Ohm

·         Signal System: NTSC

·         Image Sensor: 1/4” SONY Super HAD CCD

·         Effective Pixels: 510 x 492

·         Horizontal Resolution: 380TV lines

·         Lens: 3.6mm/92° Angle of View

·         S/N Ratio: > 48dB

·         Min. Illumination: 1.0Lux/F1.2

·         White Balance: Auto tracking

·         Shutter Speed: 1/50(1/60)-1/100,000 sec

·         Video Output: 1.0Vp-p 75 Ohm

·         Power Consumption: 12VDC, 120mA

·         Dimensions: 1.44" x 1.44" x 0.82"

 

Figure 3.7.1.4‑3: VC-806b-Audio Camera

3.7.1.5.        Images – Still

Lab is equipped with two Digital SLR cameras: Canon EOS 10D and 20D for still image photography of the experiments.

 

Table 16: 10D and 20D Specifications

 

Figure 3.7.1.6-1: 20D and 10D side by side

Figure 3.7.1.6-2: 20D and 10D back to back top view

3.7.2.   Conditioners

Listed below are the available signal-conditioning channels, charge amplifiers and power supplies. Table 8 presents a summary of the available equipment.

90 channels of Measurement Group 2300 DC Series signal conditioning which can be used with full, half, and quarter bridge configurations. This signal conditioner allows the use of either 120 or 350 ohm strain gages in a quarter bridge configuration and the amplification can be set in the range of 1 to 11000. The excitation voltage can be easily adjusted using a front panel control in the range of 0.7 to 15.0 volts.

24 channels of Measurement Group 2100 DC series signal conditioning which can be used with full, half, and quarter bridge configurations. This signal conditioner allows the use of either 120 or 350 ohm strain gages in a quarter bridge configuration and the amplification can be set in the range of 1 to 220. The excitation voltage can be easily adjusted using a front panel control in the range of 0.0 to 10.0 volts.

Miscellaneous DC power supplies, built in - house, are used to supply input voltage to linear potentiometers and Temposonic Displacement Transducers (section 2.5.2). They are built, configured and maintained as needed.

 

Table 17 : Available Signal Conditioners

Signal Conditioner Type	Number of Channels	Gain Range	Bridge Configurations Supported	Quarter Bridge Strain Gage Resistance (Ohms)	Excitation (volts)	Equipment Designation
Measurement Group 2300 DC	90	1-11000	Full, Half, Quarter	120, 350	0.7-15.0	Non-NEES
Measurement Group 2100 DC	20	1-220	Full, Half, Quarter	120, 350	0.0-10.0	Non-NEES
Generic Potentiometer power supply	20	NA	NA	NA	± 10.0	Non-NEES
Generic Temposonic power supply	35	NA	NA	± 15.0	15.0	Non-NEES
Misc. (standalone charge amps, etc.)	15	NA	NA	NA	NA	Non-NEES

 

3.7.3.   Electronic Instruments

3.7.3.1.        Oscilloscopes

The laboratories currently support one 4-channel storage oscilloscope, used mostly for instrumentation calibration and verification of signal integrity. The oscilloscope is a Tektronix model TDS224, and has storage and data acquisition functionality.

3.7.3.2.        Digital Multimeters and Voltage Standards

The lab maintains several digital multimeters, all of which are calibrated annually and are used as reference standards for in-house calibrations. Calibration data sheets are available to users who wish to verify quality of measurements

3.7.4.   Instrumentation frames

SEESL is equipped with 3 instrumentation frames. One orange frame is located next to Shake Table O in Test Area 1. Two blue frames are located next to Shake Tables A and B in Test Area 2. These frames are reference frames and are used in specimen instrumentation.

Figure 3.7.4‑1: Orange Instrumentation Frame

Figure 3.7.4‑2: Blue Instrumentation Frame

3.7.5.   Instrumentation Databases

3.7.5.1.        Instrumentation calibration

3.7.5.1.1. Lab procedures

Most of the in-house built lab equipment is calibrated on need to basis. The most recent calibration certificates as well as calibration procedures can be accessed at calibration section of SEESL (nees@buffalo) website. 

3.7.5.1.2. Calibration examples and databases

Calibration records as well as procedures can be accessed through the calibration section on SEESL (nees@buffalo) website.

3.8. Data Acquisition Systems

3.8.1.    Pacific Instruments

The 6000 Mainframe has an IEEE-488 interface for control and data output with mounting for 16 input and output modules. It supports up to 31 additional slave enclosures or up to 32,000 channels. Currently it is configured for 132 channels.

The Mainframe is running Version 8.1 of PI660 software for the 6000 DAS. That includes a variety of new features. Among the new features is the ability to acquire data simultaneously from multiple input sources. Version 8.1 includes support for the ICS-610 and ICS-645 high-speed sigma-delta digitizer boards. Each ICS-610 has the ability to digitize up to 32 channels of analog signals at a rate of 100,000 samples per second per channel. Each ICS-645 has the ability to digitize up to 32 channels of analog signals at a rate of 2,500,000 samples per second per channel. The PI660 software currently supports up to 10 of the ICS boards per system.

 

Figure 3.8.1‑1: Pacific Instruments 6000 Data Acquisition Mainframe

3.8.2.   Optim MegaDac

This is a modular, expandable system, currently configured with 128 channels of sample & hold A/D input, along with 8 channels of thermocouple conditioning and 8 output channels for playback. The Megadac is primarily used in the original Seismic laboratory for various test programs.

Figure 3.8.2‑1: Optim Megadac DAQ

 

3.8.3.   Krypton K600 Portable CMM System

The K600 is a new generation of high performance dynamic mobile coordinate measurement machine. The system combines high accuracy, a large measurement volume and full freedom of Space Probe manipulation. This solid-state system is extremely reliable.

Figure 3.8.3‑1: Krypton K600 Portable CMM System

 

Capabilities (abbreviated):

 

Measurement system / probes capabilities:

 

            1 LED                          3 degrees of freedom

            3 (or more) LED          6 degrees of freedom

 

Sampling rate:

 

            Rate  =  3000  /  # of LED  (in samples per second)

            i.e.       for 20 active LED’s  the Rate = 150 samples per second

for 50 active LED’s  the Rate = 60 samples per second

 

Field of view for K600:

 

            Minimum distance (D) from camera 1.5 m; Maximum distance (D) from camera xx m.

The field of view is defined as noted below (H = height of image, W- width of image, D = the distance from which the max view can be captured). H and W can be interchanged.  Here are the manufacturer specified field views:

Table 18: Field of view for K600         

	H	W	D
0	0.9m	0.5m	1.5m (min)
I	1.7m	1.8m	3.5m (max)
II	2.4m	3.3m	5.0m (max)
III	2.6m	3.6m	6.0m (max)

                                    Additional performance limitations see Figure 3.8.3‑2:

 

Figure 3.8.3‑2: Performance limitations of K600

3.8.4.   Dell Workstations – Portable DAQ

These systems (3 total) each consist of 16 channels of National Instruments 16 bit data acquisition input channels, 4 analog output channels, and LabView 7 Express data acquisition development system. The systems are portable and can be used in the NEES/SEESL environment as well as in the various teaching labs located throughout CSEE. To take a look at Labview user manual, as well as the manuals for other equipment available on site please refer to training manuals section of SEESL (nees@buffalo) website.

3.8.5.   Dell PC & Data Translation 12 bit Desktop System

The lab supports a varying number of these systems. They are configured as needed for up to 32 channels per PC. As the previously mentioned Dell/LabView systems are being phased into service, these systems will gradually be taken out of service due to obsolescence of hardware and software components.

3.9. Networks

3.9.1.   Description

The lab is equipped with a gigabit local area network (LAN) connected to the campus backbone with a fiber gigabit link. All IP addresses on this network are in the 128.205.20.0/24 range. Network ports are located through the lab including ports on the strong floor area, along the shake table trench, and the balcony.

 

Networking Hardware Configuration:

·         4 x Nortel Baystack 380 10/100/1000 switches

·         3 x Nortel Baystack 450 10/100 switches

·         96 1000Mbps port activations

·         72 100 Mbps port activations

A wireless network (802.11b) covering the entire lab area, collaboration room, and telepresence room is accessible to all NEES users. For security reasons, this network is firewalled and requires authorization. A VPN client is provided for secure communications, and is recommended for all users.

Figure 3.9.1‑1:Wireless access point

 

Wireless Configuration:

·         2 x Cisco Aironet 1200 Access Points

·         UB VPN Client (localized version of Cisco VPN Client)

3.9.2.   Schematics

3.9.2.1.        Wired

The 20net has connections to both Internet1 and Internet2 through the campus backbone. All network connections for the 20net originate at the switching closet in XXX Ketter.

Figure 3.9.2.1‑1: Ketter Hall network diagram

3.9.2.2.        Wireless

 

There are two wireless access points located around the SEESL laboratory. Below is a coverage map indicating the quality of the wireless signal within the lab and surrounding areas.

Figure 3.9.2.2‑1: Ketter Hall wireless coverage map

 

3.9.3.   Servers

All servers are housed in the server room (161 Ketter Hall), located on the first floor of the lab. Servers are mounted in racks with redundant and backup power supply. Dual gigabit Ethernet connections are provided to each server. There is an integrated LCD/keyboard console to locally administer all servers in the rack.

Figure 3.9.3‑1: Server room

3.9.3.1.        NEESpop

NEESgrid Point of Presence. The gateway for authorized and secure access to local site resources including telepresence, telecontrol, local data repository, and other collaboration services.

Hardware specifications:

·         Dell PowerEdge 2650

·         Dual Xenon 2.4GHz Processors

·         100GB RAID 5 Storage

·         2 x Gigabit Ethernet NICs

·         2GB of RAM

Software Specifications:

·         Red Hat Enterprise Linux 3.0

·         NEESpop 2.2

URL: http://pop.nees.buffalo.edu/

3.9.3.2.        NEES TPM

Telepresence server. Manages and provides remote access to all telepresence video/audio streams.

Hardware Specifications:

·         Dell PowerEdge 2650

·         Dual Xenon 2.4GHz Processors

·         100GB RAID 5 Storage

·         2 x Gigabit Ethernet NICs

·         2GB of RAM

Software Specifications:

·         Red Hat Enterprise Linux 3.0

·         flexTPS 1.0

URL: http://tpm.nees.buffalo.edu/

3.9.3.3.        Webserver & Domain Servers

Host for the nees@Buffalo website and controller of the NEES domain. The domain is controlled by two identical computers to act as backup for each other in case the other one fails.

Hardware Specifications:

·         Dell PowerEdge 2650

·         Dual Xenon 2.4GHz Processors

·         100GB RAID 5 Storage

·         2 x Gigabit Ethernet NICs

·         2GB of RAM

Software Specifications:

·         Windows Server 2003

·         IIS 6.0

URL: http://nees.buffalo.edu/

3.9.3.4.        Email Server

Hardware Specifications:

·         Dell PowerEdge 2600

·         Intel Xenon 2.8GHz Processor

·         36GB Storage

·         2 x Gigabit Ethernet NICs

·         2GB of RAM

Software Specifications:

·         Windows Server 2003

·         CommuniGate Pro

·         IIS 6.0

URL: http://webmail.nees.buffalo.edu/

3.9.4.   Mass Storage

The lab is equipped with 3.5 TB network-attached storage (NAS) system, Netstor MVD by Excel Meridian.  All the data in the storage is being backed up daily on Tape Drives and once a week these backup tapes are taken to an off-site storage site.

Hardware Specification:

·        Intel Pentium 4 Xeon 2.4 GHz CPU

·        2 GB DDR PC2100 ECC memory

·        400W hot-swap redundant power

·        (2) 10/100/1000Mb Gigabit Copper Ethernet built-in

·        (2) Ultra160 SCSI channels, one for external RAID array, one for external Tape Backup device

·        (1) 16-bay SATA IDE-to-SCSI RAID solution configured with 16 250 GB SATA drives in RAID5 configuration with hot spare, totaling in 3.5TB capacity.

 

Figure 3.9.4‑1: Front view of Netstor MVD

 

3.9.4.1   Data Archival and Organization

All test data is archived to the local data repository. Additionally, all configuration information from the data acquisition and control systems is archived there. The local repository is hosted on our NAS system and utilizes our redundant mass storage and backup capabilities.

Access to the data will be provided only to the project members. The project data can be made public or additional users granted access if the project members request it. The data is kept on the local repository for a time determined by the project members. Older data my be moved from the local repository to offline media to ensure the newest data is available online. But all offline data will be made available, on request, in a reasonable time period.

After a test, all data is collected from data acquisition and control systems, and transfered to the local repository. This data includes all the data and configuration files collected from the various data systems, in their original (raw) format. The data is then converted into standard formats, such as ASCII or DADiSP, for use by the researcher. Additional processing may be performed by the researcher and archived in the local repository.

The lab provides a standard template for organization of experimental data. The template provides for archival of additional information used to describe the experiment, such as description of model, instrumentation, data acquisition, and loading system. The template also captures the test plan and implementation details. The local repository may be used by the researcher to store all this additional information in the template.

3.9.5.   Telepresence

All test data is archived to the local data repository. Additionally, all configuration information from the data acquisition and control systems is archived there. The local repository is hosted on our NAS system and utilizes our redundant mass storage and backup capabilities.

Access to the data will be provided only to the project members. The project data can be made public or additional users granted access if the project members request it. The data is kept on the local repository for a time determined by the project members. Older data my be moved from the local repository to offline media to ensure the newest data is available online. But all offline data will be made available, on request, in a reasonable time period.

After a test, all data is collected from data acquisition and control systems, and transfered to the local repository. This data includes all the data and configuration files collected from the various data systems, in their original (raw) format. The data is then converted into standard formats, such as ASCII or DADiSP, for use by the researcher. Additional processing may be performed by the researcher and archived in the local repository.

The lab provides a standard template for organization of experimental data. The template provides for archival of additional information used to describe the experiment, such as description of model, instrumentation, data acquisition, and loading system. The template also captures the test plan and implementation details. The local repository may be used by the researcher to store all this additional information in the template.

 

Figure 3.9.5‑1: Camera platform mounted in SE corner of lab

 

Figure 3.9.5‑2: Telescopic tripod with camera platform

 

Hardware Specifications:

·         2 x Axis 2401 Video Servers

·         6 x Axis 2401+ Video Servers

·         4 x Axis 2191 Audio Servers

·         4 x Canon VC-C4R Cameras

·         8 x Canon VC-C4 Cameras

All telepresence video streams are accessible through the flexTPS website. High frame rate video and PTZ camera control require username and password authorization.

3.9.6.   Multipurpose Workstations

Workstations capable of controlling any data acquisition or control system in the lab. Preloaded with all the necessary software for any system in the lab. Additionally, software to quickly visualize and analyze captured data is preinstalled.

 

Hardware Specifications:

·         Dell Precision 650

·         Intel Xeon 2.66Ghz Processor

·         36GB SCSI Storage

·         2GB of RAM

·         20” Flat Panel Monitor

Software Specifications:

·         Windows XP Professional

·         PI6000

·         LabView

·         DADiSP

3.9.7.   Computational Workstations

Hardware Specifications:

·         Dell Precision 650

·         Intel Xeon 2.66Ghz Processor

·         36GB SCSI Storage

·         2GB of RAM

·         20” Flat Panel Monitor

Software Specifications:

·         Windows XP Professional

·         Matlab

·         Microsoft Visual Studio

·         SAP

·         Larsa

·         Idarc

·         OpenSees