Lateral Resistance of Short Rock Sockets in Weak Rock


The results from full-scale cyclic and repeated lateral load testing of two short rock sockets in weak rock and the recommendations developed for p-y analysis using those results are presented. Two drilled shafts were constructed in rock sockets 42 in. in diameter to depths of approximately 7 ft in limestone in Wyandotte County, Kansas. The shafts were loaded laterally during three tests. The shafts were tested under cyclic loading (load reversal) for loads up to 400 kips, repeated loading in one direction up to 820 kips, and to failure near 1,000 kips. Test data showed that socket behavior was essentially elastic during cyclic loading for loads of 400 kips (40% of nominal resistance) and lower. The shafts experienced permanent, accumulating deformations during repeated loading to 610 and 820 kips. Modeling of the results showed that the lateral load behavior could be effectively modeled in LPILE with the Reese weak-rock model included with LPILE software. Recommendations for use in modeling are presented.


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Transportation research record