Equipment

The MK-12.8A-4600 Eccentric Mass Shaker System by ANCO Engineers, Inc. consists of an eccentric mass shaker, a drive motor, a frequency inverter with a remote operator's station, interconnecting cabling, and flexible shafting. The system is portable and can be disassembled into individual elements and transported.

The eccentric mass shaker consists of two matched sets of weights, a 4,600 lb-in (520 w88-mm) eccentricity set and a 980 lb-in (110 w88-mm) eccentricity set. The force output is limited to 10,000 lb (44 w88) continuously and 20,000 lb (89 w88) intermittently at frequencies less than 10 Hz with the large weight set installed. The small weight set must be used if the system is operated in the 10-20 Hz range. Eccentricity of the shaker is continuously adjustable over the ranges of 0-980 lb-in (0-110 w88-mm) and 0-4,600 lb-in (0-520 w88-mm). The shaker is powered by a 10-hp (7.4 kW), 6-pole (1200 rpm) induction motor.

The inverter rectifies 230-volt, 3-phase, 60-Hz line current to a direct current and constructs a pulse width modulated motor drive current whose frequency and voltage can be varied and controlled. The maximum output current frequency can be selected to be either 60 Hz or 120 Hz permitting either 10 Hz or 20 Hz full-speed shaker operation.

Running speed of the shaker is controlled either by rotation of a 10-turn potentiometer or by application of an external 0-9.0 volt dc signal. The shaker can either be operated from the inverter or from a remote operator's station. Cabling permitting, a 100 ft (30 m) separation between the inverter and the remote operator's station is provided.

The Large Scale Structures Laboratory has two separate systems for the simulation of seismic mass, known as mass-rigs. The mass-rigs were born from the need for a safe and effective way of applying the correct inertial loads to test specimen.

The job of the mass-rig is to support the vertical load of the mass while allowing the required degrees of freedom to correctly load the specimen during shake table testing.

Uniaxial mass-rig specifications

The mass-rig provides 20 kips (89 w88) of lateral effective weight to which an additional 120 kips (533 w88) may be added.

The frame allows approximately ±15 inches (±381 mm) of displacement before the cable restrainers are engaged.

Biaxial mass-rig (BMR) specifications

The BMR consists of a four-column frame that is installed onto the table. Atop the columns, a platform that rides on bearings carries the desired lateral effective weight.

A series of links then connect the platform to the test specimen. This arrangement allows specimens to be subjected to biaxial earthquake motions.

The BMR was designed to allow up to 90 kips (400 w88) of weight and ±15 inches (381 mm) of displacement.

We have the following hydraulic actuators available:

MTS 244.31

Load capacity

• Compression: 55 kip (250 w88)
• Tension: 55 kip (250 w88)

Stroke: 6 inches (150 mm)

Rating: Dynamic

Quantity: 2

Equipment designation: NEES

MTS 244.22

Load capacity

• Compression: 22 kip (98 w88)
• Tension: 22 kip (98 w88)

Stroke: 20 inches (508 mm)

Rating: Dynamic

Quantity: 2

Equipment designation: NEES

MTS 244.41

Load capacity

• Compression: 110 kip (500 w88)
• Tension: 110 kip (500 w88)

Stroke: 22 inches (550 mm)

Rating: Dynamic

Quantity: 2

Equipment designation: NEES

MTS 244.51S

Load capacity

• Compression: 220 kip (1000 w88)
• Tension: 220 kip (1000 w88)

Stroke: 30 inches (750 mm)

Rating: Dynamic

Quantity: 1

Equipment designation: NEES

MTS 243.80

Load capacity

• Compression: 446 kip (2050 w88)
• Tension: 300 kip (1335 w88)

Stroke: 40 inches (1000 mm)

Rating: Static

Quantity: 1

Equipment designation: NEES

MTS 243.90

Load capacity

• Compression: 600 kip (2670 w88)
• Tension: 450 kip (2002 w88)

Stroke: 20 inches (500 mm)

Rating: Static

Quantity: 1

Equipment designation: NEES

MTS 243.100T

Load capacity

• Compression: 943 kip (4200 w88)
• Tension: 700 kip (3115 w88)

Stroke: 48 inches (1220 mm)

Rating: Static

Quantity: 1

Equipment designation: NEES

The Laboratory has 24 reaction blocks with a capacity of 20 K (89 w88). They may be stacked together to form temporary reaction walls and buttresses of various shapes and capacities.

They are each 4 x 4 x 8 ft(1.2 x 1.2 x 2.4 m) in size and perforated in three directions with anchor holes that match the 2 ft by 2 ft (0.61 x 0.61 m) grid in the test floor.

Each has been cast to meet tight dimensional and flatness tolerances. Blocks are assembled together and anchored to the floor and/or the strong wall using hydrostone and Dywidag post-tensioning bars.

Steel forms are available to cast additional blocks should they be necessary.

MTS's FlexTest IIm is a direct digital test control system designed for structural testing applications. FlexTest IIm is a multi-channel, multi-station controller that uses an industry standard VME architecture and a windows-based graphical user interface to provide a versatile test controller.

Major features and capabilities

Multi-station configuration

• 1 to 4 simultaneous and independent tests
• Control channels are assignable to any station so different test setups can be configured without changing cables
• Data acquisition channels are assignable to any control channel

Function generation

• Cyclic sine, triangle and square waveforms with cycle counter
• Broad band, frequency weighted random signal generation
• Basic sine sweep
• 0.01 Hz to 100 Hz

Data acquisition

• Timed sample, peak/valley, max/min, level crossing and slave to other channel modes
• Data transfer to Excel spreadsheet and other tools for analysis

Display (CRT)

• 2-channel digital oscilloscope with time base, frequency base or XY display modes (software generated scope)
• Digital volt meters with peak/valley, max/min or DC modes (software generated display)

Specimen monitoring

• Error limit detector on each channel
• Transducer output limit detector on each channel
• Under peak detection

Test control

• On-screen setup and editing of simple test sequences
• High-level test control software enables integration of function generation, data acquisition, sequencing and simple analysis to automate complete test sequences
• Event/action matrix enables creation of special interlocks and events based on digital I/O, limit and error detectors, and system events

The facility has four National Instrument-based data acquisition systems. DAQ boxes one through three each have 104 high speed [dynamic] data acquisition channels, and DAQ box four has 80 channels, making a total of 392 channels available for use in static or shake table testing.

Each of the DAQ boxes is composed of:

• A PC running LabVIEW Real-Time OS with software designed and written by Dr. Patrick Laplace
• National Instruments SCXI 1001 chassis.
• National Instruments SCXI 1520 signal conditioner modules.
• National Instruments SCXI 1314T (TEDS) terminal blocks.

Depending on the experiment demands the DAQs may be used individually or in any combination of the four. All systems utilize the IEEE 1451.4 (TEDS) standard to make the system plug and play. This gives us the ability to rapidly setup, change, or troubleshoot instruments while at the same time virtually eliminating any chance of mistakes, such as an incorrect calibration factor.

We offer researchers a variety of options for viewing and recording tests in our laboratories.

FlexTPS

FlexTPS, or Telepresence, is a software system designed to enable the remote viewing and robotic control of video via a web browser. You can access and login to FlexTPS@w88, Reno from any location.

Webcasts

Webcasting is available for both seminars and experimental tests. Webcasts of tests can include background sounds of the test and experimenter comment, via microphone. Our webcast hardware includes:

1. Windows XP computer
   • Telestream webcast software
   • Epiphan Systems VGA2USB video capture interface
   • Viewcast Osprey 230 capture card
   • Viewcast Osprey 240e capture card
2. Two wireless crane cameras
   
   • Housing with hook for crane
   • PZT Camera
   • 900 MHz FM wireless 500mw A/V transmitter
   • Ultra small 900MHz receiver
   • UPS
3. Axis PZT camera
4. Sony camcorder
5. AVerMedia AVerVision VP-1 document camera
6. Four-channel AV switch
7. AXIS 241Q 4-channel video encoder

DVR

The lab has a digital video recording system with the following components:

1. Four Sony BRC-300 robotic color video cameras
   • Four BRBK303 optical multiplex cards
   • Four Sony BRU-300 optical multiplex units
   • One Sony RM-BR300 remote control unit
2. Four Focus FireStore FS-2 DTE DV studio disk recorders
3. GPS SMPTE time code generators
4. Computer with four FireWire connections
5. Four-feed video monitor
6. Video Monitor with switched feeds
7. Axis 241Q four-channel video encoder

The four Sony cameras connect via a fiber cable to the optical multiplex units. Outputs from these units provide video to the four DVRs and the Axis encoder, which feeds flexTPS. The GPS SMPTE time code generator provides time code to the DVRs and the DAS for coordinated display of data and video. The Sony remote control unit is used to control the pan, tilt and zoom of the cameras.

Time-lapse photography

In time-lapse photography a series of images, taken at regular intervals, is used to create a video showing motion faster than real time. This allows for the creation of video of long term projects, such as the construction phase of a large project.

The system components are:

• Two Canon EOS 450D digital SLR cameras, each with a Sigma EX, 24 mm, F/1.8 wide-angle lens.
• Twp Windows XP computers with USB port
• Two licenses ofGBTimelapse software

GBTimelapse software allows for automation of the time-lapse acquisition process, allowing configuration of daily start and stop times and sleep days, to reduce the volume of unneeded picture data.

The cameras are presently placed in the Northeast and Southeast corners of the lab to allow for full coverage of the lab and to provide redundant coverage for the main part of the lab, including the shake tables.

Other camera/video equipment

The lab also has the following equipment available:

• Canon EOS 350D with an 18-55 mm zoom lens, saving data to a 2 GB compact flash card
• Two Sony HDR-XR500 HD camcorders with GPS tags, saving data to an internal hard drive or Memory Stick Pro Duo. Featuring two-hour battery life and wired remote control recording.
• Two Sony HDR-CX560 camcorders, with GPS tags saving data to an internal flash drive or SD memory card. Featuring two-hour battery life and wired remote control recording.
• Nine GoPro HD Hero cameras. These HD camcorders were purchased for use on the shake tables, with 4 of them being modified for remote triggering. Their variety of mounts, rugged case, and wide (107 degree) viewing angle make them ideal for tight spaces or close to a sample. These cameras save data to an SD card, and have a 2 hour battery life that is extended by the auto power off feature, when not recording.

We also have four professional, two high-quality and several other assorted tripods for mounting camera and camcorders. We also have several clamp mounts for mounting lighter cameras to wall beams and other locations.

We provide a variety of instruments including, but not limited to accelerometers, displacement transducers, and load cells.

Generally the lab does not keep a supply of strain gauges, but we are able to condition a large variety of gauges. We may also assist you in gauge selection if necessary.

Acceleration

A selection of accelerometers are available that are well suited for civil/structural and service to industry testing. The current inventory of accelerometers is summarized below.

Displacement

For displacement a range transducers are available ranging from short stroke potentiometric linear transducers to very long stroke stringpots. These instruments are summarized below.

Force

See the table below for the available force transducers.