Researchers and students working in the structural testing laboratories determine how well structures hold up to a variety of environmental conditions through simulating earthquakes; snow drifting; soil dynamics and more!

Additionally, the department has a 300-kip capacity Baldwin Universal Testing Machine and has access to numerous other servohydraulic testing frames.

A student-oriented machine shop is available for fabricating test specimens and a Sensors and Instrumentation Laboratory is available for applying strain gages to test specimens. In addition, laboratory technician support is available to assist with fabrication of test specimens and setting up data acquisition and control systems.

Seismic Shaking Table

Located in the Jonsson Engineering Center High Bay Laboratory, the Seismic Shaking Table is used for both structural testing research projects and as an educational tool for both undergraduates and graduates.

The shaking table offers researchers:

• A 2.59 m x 1.63 m table platform area
• A payload capacity of approximately 45 kN
• A maximum acceleration, velocity, and displacement of approximately 5 g, 30 cm/s, and +/-13 cm.
• A servo-controlled hydraulic actuator with a rated capacity of 100 kN and a stroke capacity of 12.7 cm that drives the table. This actuator is controlled by a closed-loop PIDF controller that utilizes the actuator displacement as the feedback signal.
• A 7.5 ton crane with a clearance of about 4 m from the top of the shaking table platform accomodates large-scale projects.

Reproducing random motions for seismic testing and accurately recording the data

The shaking table is capable of reproducing a variety of input motions including random motion for system identification testing and historical earthquake records for seismic testing. A variety of dynamic measurement sensors are available for data collection including a spectrum analyzer for processing the measured signals and a National Instruments® data acquisition/control system with maximum acquisition and output rates of 333 kHz.

Benchtop Seismic Shaking Table

The benchtop shaking table system allows researchers to perform pilot studies at a small scale. In addition, the benchtop shaking table is an excellent tool for providing instruction to both graduate and undergraduate students on the topics of structural dynamics and earthquake engineering.

Features include:

• A 0.5 m x 0.5 m table platform area
• Operational frequencies from 0 to 20 Hz
• A displacement range of +/-15 cm
• Velocities up to 84 cm/sec
• Accelerations up to 2.5 g
• A maximum payload of 150 N
• Dedicated data acquisition/control system

Hydraulic Flume

Located in the Russell Sage Laboratory, the hydraulic flume is used for studying drifting of snow on low-rise buildings.

How it works:

1. During a test, a physical model of a building (approximately 1:30 scale) is placed in the flume and a suitable substitute for snow is placed on the roof of the building (see lower photo).
2. The flume is filled with water to mimic the effects of air. The water is then forced to flow past the model (to mimic the effect of wind) so as to produce drifting of the snow.
3. The flume is then drained and the measured snow drifts are used to develop recommendations for modifications to existing building code documents.

Split Soil Box

The Split Soil Box is used in conjunction with the department's 100 g-ton centrifuge to study the behavior of buried pipelines subjected to lateral offsets due to earthquake faulting.

How it works:
The split box (100 cm x 35 cm x 20 cm) consists of two regions that can be laterally offset via a hydraulic actuator. A reduced-scale pipeline segment is installed within the box and the two regions are filled with soil. The box is then inserted in a 100 g-ton centrifuge which is spun at high speeds to produce high centrifugal forces so as to induce the appropriate stress conditions within the soil.