预制高强混凝土薄壁钢管桩受弯性能试验研究

Experimental study on behavior of TSC pile subjected to pure bending

本文结合直径400 mm长5 m、直径600 mm长5 m和直径800 mm长15 m的预制高强混凝土薄壁钢管桩的纯弯试验,研究了不同桩径、桩长对预制高强混凝土薄壁钢管桩抗弯性能的影响,同时对预制高强混凝土薄壁钢管桩在纯弯作用下的破坏机理进行了分析,并对《预制高强混凝土薄壁钢管桩》中的预制高强混凝土薄壁钢管桩桩身极限弯矩的计算公式进行了可靠性分析。试验结果表明,预制高强混凝土薄壁钢管桩具有良好的抗弯工作性能,在挠度发展较大的情况下仍能继续承载。然后分析了跨中截面应变的变化规律,弯矩-挠度曲线没有出现下降段,构件体现出良好的延性。最后对预制高强混凝土薄壁钢管桩桩身极限弯矩计算公式进行了验证,经对比,吻合较好,说明使用该公式计算预制高强混凝土薄壁钢管桩抗弯承载力是可行的。

Based on the experimental results of TSC pile（ Precast thin-wall steel and spun concrete composite pile） with the diameter 400 mm and the length 5 m, TSC pile with the diameter 600 mm and the length 5 m, TSC pile with the diameter 800 mm and the length 15 m, in this paper the influence of the diameter and the length on pure bending bearing capacity of TSC pile was analyzed, the deformed mechanism of the pile was studied, and the reliability of the design formula for TSC tension members in ＂Precast thin-wall steel and spun concrete composite pile＂ was analyzed. Experimental results show that the capacity of TSC pile subjected to pure bending is satisfactory with the practice. Concrete strain in the middle section of the pile is studied, and curves of bending moment-deflection shows no descending segments, which means the outstanding ductility of TSC pile. The formula of capacity of TSC pile subjected to pure bending with the experimental data was also compared, and the results are acceptable.