Earthquake Shake Test
Overcast Innovations recently travelled to the Structural Engineering and Earthquake Simulation Laboratory (SEESL) of the University at Buffalo and subjected our Overcast Cloud product line to incremented levels of triaxial earthquake shaking. The objective of the test(s) was to seismically qualify the torsion spring design of our integrated ceiling assembly per the International Building Code (ICC, 2018) as detailed in ICC ES ACI 156 (ICC, 2020). The torsion spring system (designed to hold finish panels tight against our frame during a seismic event) held panels in place under the most rigorous test at a short period spectral acceleration (Ss) of 3.0 g.
Overcast’s torsion spring systems’ capability of withstanding short period spectral acceleration test of 3.0 g exceeds areas in the country with the highest earthquake hazards like Los Angeles, California at 2.26 g. See the Los Angeles map and data below from the ASCE 7 Hazard Tool below as an example.
Many vertical and horizontal accelerations were tested from 0.25 g to 3.0g. The random multi-frequency seismic simulation experiments supporting the test frame included triaxial acceleration time series characterized by motions at the level of the platform of the earthquake simulator extension (i.e., floor motions) (pictured below).
The test frame increased the movement from the level of the simulator platform to the points of attachments of the frame to the suspension and ceiling system. Visual inspection was used to assess the ceiling system after each test. Findings revealed no visual damage throughout the course of testing.
Safety is at the forefront of everything we do at Overcast and we subject our products to this type of testing so that we have confidence that they exceed the highest industry standards.