摘要
为了解决河道护岸和基坑围护工程中普通预应力混凝土管桩水平承载力低及变形延性差的问题,研发了预应力钢绞线超高强混凝土H型桩.通过对2种规格的8根H型桩试件进行足尺抗弯及抗剪性能试验,研究H型桩的抗裂性能、抗弯(剪)承载力、变形延性及破坏特征.结果表明:预应力钢绞线超高强混凝土H型桩抗弯破坏模式为受压区混凝土压溃,抗剪破坏模式为斜截面剪压破坏;抗弯试验桩身竖向裂缝较多且分布均匀,抗剪试验桩身裂缝较少且斜裂缝出现滞后于竖向裂缝;试件抗裂弯矩和开裂剪力试验值与规范公式计算值相近,极限抗弯承载力较计算值偏大约30%.对比预应力超高强混凝土管桩抗弯试验结果表明,H型桩具有更好的变形延性和整体性.
Prestressed steel strand ultra-high strength concrete H-type piles were developed to solve the problem of low horizontal load-carrying capacity and poor deformation ductility of ordinary prestressed concrete pipe piles in river bank protection and foundation pit retaining engineering. The anti-cracking performance, flexural and shear load-carrying capacity, deformation ductility and failure characteristics of H-type piles were analyzed through fullscale flexural and shear performance experiments of eight H-type pile test specimens of two kinds of specifications. Results show that the flexural failure mode of prestressed ultra-high strength concrete H-type piles is the concrete crushing in the compression zone, and the shear failure mode is the shear-compression failure of the oblique section. The flexural test piles have more uniformly-distributed vertical cracks, while the shear test piles have fewer cracks and the oblique crack lags behind the vertical cracks. The experimental results of the cracking bending moment and the cracking shear force for test specimens are close to the calculated values of the code formula, and the ultimate bending bearing capacity is about 30% larger than the calculated value. The comparison with the flexural test results of prestressed ultra-high strength concrete pipe piles shows that the H-type piles have better deformation ductility and integrity.
作者
张正旋
陈刚
徐铨彪
龚顺风
肖志斌
刘承斌
ZHANG Zheng-xuan;CHEN Gang;XU Quan-biao;GONG Shun-feng;XIAO Zhi-bin;LIU Cheng-bin(Institute of Structural Engineering, Zhejiang University, Hangzhou 310058, China;The Architectural Design and Research Institute of Zhejiang University Co. Ltd, Hangzhou 310028, China)
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2019年第1期31-39,共9页
Journal of Zhejiang University：Engineering Science
基金
浙江省重点研发资助项目(2018C03033-1)
国家自然科学基金资助项目(51479176
51009122
51779223)
关键词
H型桩
超高强混凝土
钢绞线
抗弯性能
抗剪性能
H-type pile
ultra-high strength concrete
steel strand
flexural performance
shear performance
