01033570

Component

This paper describes how drilled shafts socketed into rock have been widely used as a foundation for bridges to resist both vertical and lateral loads. Although numerous research efforts on rock socketed drilled shafts under vertical loads have been carried out, research efforts on rock socketed shafts under lateral loads have been lacking. The paper presents the results of a testing program that was designed to validate the calculated design capacity of the drilled shafts socketed into rock for both vertical and lateral loads. The testing was conducted on two 8 feet (2.44 m) diameter drilled shafts. The two shafts were instrumented with Osterberg load cells (O-CellTM) for vertical load testing, and fully instrumented for lateral load testing. The effect of the overburden soil around test shaft 2 was isolated by using 11 feet diameter casing during the load test. Test shaft 1 was terminated in shale while test shaft 2 was constructed 10 feet deeper to bear on siltstone bedrock. The vertical load testing on shaft 2 broke the world record with a maximum applied load of 36,100 Kips (161 MN). The lateral load test was conducted after the vertical testing was completed, and the maximum load induced a movement of approximately 0.25 inches at the top of rock. The results of this load testing program verified the adequacy of the design assumptions, and can be used to verify the existing published analysis methods that are still in their early stage of development due to limited lateral load test data

01020180

06-2683

English

23p

2006

Transportation Research Board 85th Annual Meeting

CD-ROM

Figures (12) ; References (5) ; Tables (2)

Bridge foundations; Data collection; Load tests; Soil tests

Drilled shafts; Lateral loads; Osterberg cells; Rock sockets; Vertical loads

Ohio River

Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls

Transportation Research Board Annual Meeting 2006 Paper #06-2683

PRP, TRIS, TRB

Mar 3 2006 11:05AM