Model tests on uplift behaviors of single batter piles in sand
CAO Weiping1，QIN Qiangyi1，2，ZHAO Min3
(1. School of Civil Engineering，Xi?an University of Architecture and Technology，Xi?an，Shaanxi 710055，China；
2. SCEGC No. 1 Construction Engineering Group Company Ltd.，Xi?an，Shaanxi 710068，China；3. School of Civil and Architecture Engineering，Xi?an Technological University，Xi?an，Shaanxi 710032，China)
Abstract：In order to reveal the uplift bearing behaviors and load transfer mechanism of vertically loaded batter piles, 10 model tests were conducted for single batter piles embedded in dry medium dense sand. The influence of shaft inclined angle and the ratio of the pile length to shaft diameter(L/D) on the uplift bearing capacity was investigated；and the characteristics of the axial force，the bending moment，the shear force and the average skin friction on pile shaft was analyzed. The difference of the uplift bearing capacity between the batter piles and its vertical counterparts was also studied. Results indicate that the uplift bearing capacity of the batter pile is not always bigger than that of the vertical pile，which notably depends on the shaft inclined angle and the ratio of the L/D. The magnitude of the axial force in batter pile induced by uplift is greater than that in vertical pile，the bigger the inclined angle，the greater the axial force of the batter piles over that of the vertical piles. Both the bending moment and shear force caused by uplifting on the upper segment of batter piles are influenced by the inclined angle and the ratio of L/D. With the exception of a maximum shear force occurring on the pile head for batter pile，an extreme value of shear force will also be caused in the inclined shaft below the pile head. Negative skin friction exists on the upper segment while positive skin friction on the lower segment of the inclined piles.
曹卫平1，秦强毅1，2，赵 敏3. 砂土中抗拔斜桩性状模型试验研究[J]. 岩石力学与工程学报, 2019, 38(S1): 3124-3133.
CAO Weiping1，QIN Qiangyi1，2，ZHAO Min3. Model tests on uplift behaviors of single batter piles in sand. , 2019, 38(S1): 3124-3133.
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2019, Vol. 38 
