Abstract: According to the preloading destructive test on small diameter steel pipe rowed piles, with a landslide worksite as the pile load test area, the horizontal load-displacement curve of different combinations of the structures was obtained. During the preloading test, when the load was increased to a limited value, the infection point of deformation curve appeared; when the load reached the ultimate value, large deformation of pile tops and partial outflow of the soil between piles appeared. However, the whole collapse or buckling failure of the steel pipe pile did not occur. According to the slow loading method, the ultimate horizontal bearing capacity of two rows of piles and three rows of piles was determined with different pile spacing and row spacing. The conclusions are drown by the tests that a composite bearing system is built through interaction of the steel pipe piles and soil between piles, and it greatly increases the bearing capacity of the small diameter steel pipe piles compared with the system without considering the action of soil between piles. Such factors as the bent structure strength, rows of steel pipe piles and reasonable row spacing affect its bearing capacity.

Key words: getechnical engineering;landslides, small diameter steel pipe piles, prototype test, horizontal bearing capacity, soil between piles

摘要： 以某滑坡工点作为堆载试验场地进行小直径钢管排桩原型结构堆载破坏试验，获取了不同组合结构的水平荷载-位移曲线。加载试验中，钢管排桩在荷载增大至一定限值，变形曲线出现拐点，达极限破坏时，桩顶出现大变形，桩间土局部溜出破坏，但钢管桩未发生整体垮塌或溃屈破坏。按照慢速维持荷载法，确定了两排桩、三排桩不同间排距结构的水平极限承载能力。试验表明：钢管排桩通过桩体与桩间土相互作用形成复合承载体系，承载能力较不考虑桩间土的排架结构大幅提高，其承载能力影响因素包括排架结构强度、钢管桩排数及合理间排距等。

关键词: 岩土工程, 滑坡, 小直径钢管桩, 原型试验, 水平承载力, 桩间土