Materials Used:
Existing pilot simulation centrifuge structure with cast-in-place piles and concrete wing walls.

Project Highlights:
Phase 1 of this project consisted of a finite element fatigue stress analysis of the structure along with instrumented testing by Technicon Engineering Services.

Phase 2 resulted from an upgrade to the pilot simulation centrifuge. In order to achieve a faster application of flight “G” forces, a new motor with a larger torque and a new transmission were installed into the existing module. Our office analyzed the CFET structure with the new motor. We determined if the deflections of the structure were within allowable tolerances if the counter-weights were removed and unbalanced forces were resisted. The cast-in-place piles and concrete wing walls were modeled using compression only soil springs using elastic foundation parameters that varied with the depth and soil type.

Materials Used:
The test set-up included typical materials and connections used on Southern Bleacher projects for the past 25 years: aluminum planking, wide flange steel frame members, and typical rod bracing.

Project Highlights:
Sand bags were used to simulate vertical loads at 240 pounds per lineal foot, two times the magnitude of code requirements. Sway loads were imposed at each seat level by hydraulic rams at force levels exceeding three times the code required sway loads. Electric potentiometers were placed along the top and bottom flange of the stringers at five points along the length of each stringer. The objective of the test was to verify the performance of a typical Southern Bleacher Grandstand and more specifically, to verify the load path for lateral loads applied at the seat board level. The 17 row bleacher test specimen performed very well and was able to support the two times code prescribed gravity live loads in combination with over three times the prescribed sway loads.

Project Highlights:
This project consisted of devising a method to remove the existing spillway gates and prepare the dam for the installation of upgraded gates in order to assure the dam’s ability to function properly in case of a flood. The dam was built in 1941 and was beginning to show signs of wear. Our firm utilized the crane capacities on-site to prepare the removal plan for the enormous gates. Our role also included analysis of all the existing walkway structures. The walkways and their connections were retrofitted as required to create a safe construction environment during the spillway gate change-outs.