关键词: 抗拔桩, 自平衡法, 承载力, 静载试验, 桩顶深埋

Abstract: The head of the uplift piles in the deep excavation of the T2 Shenzhen Qianhai integrated transportation hub are embedded 29 meters below the ground. The tensile capacity of these piles was tested by using a selfbalanced load testing device. The strain gages were installed at the reinforcement bars near the pile head so that effect of the overburden soil above pile on the uplifting capacity could be eliminated. A total of six piles were load tested and the Q-s curves (upliftingdeformation curves) had a shape of gradual change and met the design requirement. It is concluded that the selfbalanced load test has the advantage of simple equipment, no reactions at the ground surface and short testing duration.

Key words: tensile pile, self-balanced load test method, uplift capacity, static load test, pile top deeply embedded