40188-4A-RFP - Seismic Table

THE DELIVERABLES
The Multi-Hazard Research Facility at the Water Resources Laboratory of the University of Ottawa aims to provide experimental research infrastructure for simulating the effects of multiple natural hazards, either individually or in combination, on civil engineering infrastructure. An important aspect of the facility is the ability to simulate the effects of seismic-induced ground excitations in combination with either large waves due to wind-generated coastal storms or seismic generated tsunami solitary waves or river currents by means of a Multi-Hazard Simulator (MHS). This will be implemented through the individual or combined use of a seismic table built in the University of Ottawa’s 30 flume with either wave or current generators. The 31 m long flume will also be equipped with a sediment recirculation system to simulate the steady supply of sediment by river flow, although this feature will not be used in combination with the seismic table. Figure 1 illustrates a schematic view of the MHS. The seismic table is envisioned to be positioned in between the existing flap gate dam-break / tsunami wave generator and the new wave generator, i.e., about 5.1 m from either wave generator at approximately 21.5 m from the west lab wall.   

The MHS Flume is built with a concrete wall on the south side of the laboratory and a steel frame with glass panels on the north side. The flume has a total length of about 31 m from the east end to the west wall which delineates the outlet wall. It has a cross-sectional dimension of 1.5 X 1.5 m, with a maximum still water depth of 1.2 m. The flume is serviced by high-capacity pumps (2 x 0.5 m3/s = 1.0 m3/s) that draw from a large (300 m3) water storage reservoir situated below the flume bed. Refer to Figure 1: Multi-Hazards Simulator. For further information regarding the installation site and current infrastructures, please refer to Appendix L – Investigation and Recommendation Study.

Proponents’ proposals must include the manufacture, supply, delivery, installation and training of the unidirectional seismic table capable of operating while submerged in water. The use of the seismic table should permit relocation to outside the flume for in-air testing. Proponents’ proposals must also include the design of an appropriate sealing system to isolate the seismic table’s hydraulic or electro-mechanical components from the surrounding water. In addition, Proponents’ proposals must allow for the removal of the seismic table and all its components to enable hydraulic testing in the absence of the table.

STATEMENT OF WORK 
1. Background 
1.1 - Requirements-Specifications and Environment 

A unidirectional earthquake simulator, in the form of a seismic table is planned to be built in the hydraulic flume for testing scaled models under combined hydraulic and seismic loading. The seismic table should be designed and installed such that it can be used in the presence of wave or current generated hydraulic loads (wet application) or removed and reinstalled outside the flume for in-air testing (dry application) independent of the hydraulic loads. When removed from the flume, the installation should permit the use of the full depth of the flume for hydraulic testing. As such, the sealing of the seismic table from the surrounding water becomes of paramount importance, not only for proper operation of the table, but also for ensuring uninterrupted water flow without any turbulence associated with potential obstructions that may be caused by the sealers, with or without the seismic table in the flume.

The seismic table platform dimensions are envisioned to be 1.5 m wide (north-south direction) and 4.5 m long (east-west direction). It can be powered either by a hydraulic or an electromechanical uni-directional actuator. The actuator can be housed below the surface of the seismic table platform and above the surface of the flume. Hence, the table will be self-contained and secured to the surface of the flume floor. Figure 2 illustrates a generic unidirectional seismic table. The bottom supporting steel plate for the seismic table can be placed on the inside surface of the flume. A false floor with a height equal to that of the seismic table would be installed along the entire length of the flume and be connected to the surface of the seismic table. The latter should be equipped with appropriate flexible water sealants, which should connect it to the false floor and permit the operation of the table without dampening the system. While the University of Ottawa will be responsible for the fabrication and installation of the false floor based on the seismic table specifications, the Supplier shall ensure its proper integration with the surface of the table. The overall depth of the seismic table, between the flume surface and the top platform should ideally be less that 500 mm. 

If a hydraulic system is to be used, a hydraulic pump with sufficient capacity in terms of gallons per minute, should be installed separately to drive the seismic table at specified maximum frequency and stroke limits. If an electromechanical actuator is to be used, the laboratory is equipped with a sufficient power supply to run both the actuator and the wave maker simultaneously.

The testing requirements dictate a minimum payload of 2.0 tons for the seismic table. The maximum acceleration of the table during testing should be at least 1.0 g with a maximum velocity of at least 1.0 m/s.  The minimum range of frequencies range should be 0.1 – 15 Hz. The maximum actuator stroke range should be no less than ∓    150 mm. The movement of the seismic table would be 1-D (one dimensional) in a horizontal direction aligned with the longitudinal axis of the flume.

The seismic table will be computer-controlled with a dedicated controller and a computer, including the necessary transducers and instrumentation for running the system. The software provided should be capable of generating realistic earthquake records based on the ground motion characteristics provided by the user. The proponent is expected to provide information on possible compatibility of the controller and the software with those of the wave maker for potential coupling of the two operations for multi-hazard actions without a time lag. This is also important for recording of the input data that drive the systems, as well as the integration with the data acquisition system that will be used to collect data from the specimen being tested.

It should also be noted that the correctness and precision of the information provided, including the drawings and plans for the laboratory facilities cannot be guaranteed but shall be consider as orientation for preliminary planning. Therefore, it is mandatory for the proponent to confirm all the existing constraints and the precise geometrical dimensions prior to the award of the contract.
 
The technical requirement listed above or proposed alternative should be provided and are expected to be included in the contractual agreement with the selected Proponent and use a performance measurement.

• Electrical power: Where is the power connection needed and how much power does the seismic table system need (diagram for average and peak values)?
• Cooling system, if cooling the motors is necessary.
• Connecting elements between the seismic table and the false floor while ensuring the seismic table is submersible.
• Dynamic forces: The bidders should explain how will, during seismic force generation, occurring forces be transferred into the supporting construction of the MHS flume? How large will these forces be?