29th October, 1989
Sydney Geological and Mining Museum
Earthquake Exhibit #9, Status Report
SIMULATOR DESCRIPTION
Under direction from the Museum, and with reference to the shortcomings of earthquake simulators in The London Geological and Mining Museum and The National Science and Technology Centre in Canberra, Latitudes has produced a concept for the design of a simulator that will provide the Museum with a major attraction that will both entertain and provide information on the nature of earthquakes.
The concept is a modular walkway system that is an integral part of the total exhibit area. The system is a paved, polyurethane walkway overlaying an array of transverse support beams, with each beam connected at either end to an airbag actuator. These airbags can be inflated sequencially to induce a peristaltic wave form through the walkway. This peristaltic movement will simulate the surface waves associated with an earthquake. The vertical movement of the floor is up to 75mm.
Compression and shear waves will be simulated by additional hydraulic actuators operating horizontally to provide approximately 10mm to 20mm movement along the X and Y axes.
The flooring system will operate in conjunction with a number of associated special effects to heighten the experience. These will include:
1. A section of false airconditioning ducting and a false beam that will become dislodged and fall partially into the exhibit space.
2. A cable tray that will become dislodged and spill a bundle of electrical wiring which will appear to throw a shower of sparks into the exhibit space, possibly with an associated smell of ozone.
3. Lights that will flicker and dim and projected images of earthquake destruction that will chase across the walls of the exhibit to increase the feeling of dislocation.
4. A soundscape that begins with distant rumbling and builds in intensity to the sound of falling buildings etc.
The simulator will be coupled to a device which describes the exponential nature of the Richter scale of intensity. A series of 10 spheres ranging from 3mm to 3000mm in diameter, each representing a point on the Richter scale, will illuminate progressively to show the relationship of the floor movement to intensity.
Two interactive displays are to be included describing:
1. The function of a seismograph. This will comprise two working model seismographs, one to measure vertical movement and one to measure lateral movement on a resiliently mounted baseboard. The vistor will be able to shake the baseboard and observe the measured movement.
2. The way in which earthquake waves are propagated. This will be a mechanical wave model which will be activated by the visitor and allow them to observe the three types of waveforms associated with an earthquake and the way in which they are propagated.
CURRENT STATUS
As requested by the Museum, a preliminary design stage has been completed by Latitudes and a prototype of approximately 2500mm by 1000mm has been built and tested. The test results have been encouraging and functionally the flooring system will provide the basis of a prime attraction for the Museum. A period of accelerated life testing should now be undertaken in parallel with the detail design of the exhibit.
As a result of the rationalisation of the Formation Floor it has been proposed that the Earthquake be relocated to an area where it will benefit greatly from additional floor space. This will allow improved visitor access to the Earthquake, the contextual integration of the exhibit into the Formation Floor, and in conjunction with the new visual treatment of the space will greatly enhance the experience.
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