Abstract of the final report "Force deflection characteristics of guardrail posts; FHWA-RD-88-193": Fifty-seven pendulum, 6 static and 4 full-scale tests were conducted using instrumented posts and standard and non-standard full-scale installations in order to create and validate a post-soil interaction model and a chart of post length vs. foreslope rate and distance to slope. Pendulum tests were conducted in flat and level soil and in soil with a foreslope. Full-scale tests were conducted with standard and non-standard installations. A full-scale test conducted with a 7-ft post G4(1S) system redirected a 4500S vehicle at 60 mi/h and 25 degrees. A test with a standard 6-ft post G4(1S) system also redirected the vehicle but with more vehicle penetration. The full-scale test results validated the pendulum test results. The 6-ft posts pushed away without bending while the 7-ft posts yielded before the soil pushed away. The report presents details on the instrumented post design, the laboratory testing, the analytical model work and the full-scale testing. (A)
Abstract