FIELD TEST STUDY ON ULTIMATE SIDE RESISTANCE OF UPLIFT PILES IN WEATHERED SANDSTONE

In order to study the distribution characteristics of ultimate side resistance of even-section piles in weathered sandstone, field tests were carried out on the basis of the national network Pingfule 500 kilovolt double-circuit project. According to the test results, the ultimate side resistance of 11 even-section piles was analyzed. The results show that the value of ultimate side resistance of pile increases linearly with the increase of soil depth; in strong/moderately weathered sandstone, the ultimate side resistance of pile increases with the increase of embedded rock depth. In this test site, the average ultimate side resistance of soil layer, strongly weathered sandstone layer and moderately weathered sandstone layer is 91.3 kPa, 456.83 kPa and 1015.3 kPa respectively. Comparing with the current codes, it is found that the calculation results of the codes are conservative. The test results in this paper have certain reference significance for the design of uplift piles in similar strata.