钢纤维混凝土桩承载特性模型试验  

Analysis of Load Capacity Behaviors of Steel Fiber Reinforced Concrete Piles Through Model Tests

作　　者：欧阳芳[1] 张建经[1] 邓小宁 韩建伟[1] 毕俊伟 杜林[1] 

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]中国郑州中核岩土工程有限公司,郑州450002

出　　处：《上海交通大学学报》2016年第3期364-369,376,共7页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金重点项目(41030742);国防基础科研计划(B0220133003)资助项目;海上风电工程地质勘测关键技术研究(GW-KJ-2011-18)

摘　　要：为研究钢纤维混凝土桩在竖向荷载作用下的承载力、桩身应变特点以及桩体的破坏现象,就不同直径的钢纤维混凝土桩和素混凝土桩进行了静载试验.沿桩体纵向布置应变片,监测其应变.试验完成后,开挖出桩体,对比分析钢纤维混凝土桩和素混凝土桩的破坏特点.结果表明:掺入钢纤维能有效增大桩体抵抗压缩变形的能力;钢纤维混凝土桩桩径由4.5cm增至7.0cm时,桩体抵抗压缩变形的能力增大,单桩极限承载力增大,但当桩径由7.0cm增至8.0cm时,桩体的压缩变形和极限承载力变化较小;2种桩体发生破坏时均为桩体两端出现裂缝甚至破损,钢纤维有效地提高了素混凝土桩的抗裂性能.根据试验结果,给出了设计钢纤维混凝土桩的几点建议.Static load tests of concrete piles of different diameters with and without steel fiber were conduc- ted to study the hearing capacity, the characteristics of strain, and the damage phenomenon of steel fiber reinforced concrete piles under vertical loads. Strain gauges were arranged along the longitudinal direction of the piles in order to measure the strain. Besides, a comparative analysis of the damage features between the steel fiber reinforced concrete pile and the concrete pile was conducted with the excavated piles after the completion of the tests. It is found that the compression deformation of the concrete pile can be effectively decreased with the steel fiber. The steel fiber reinforced concrete pile of the diameter equal to 7.0 cm has less compression and larger ultimate bearing capacity compared to that of the pile with the diameter equal to 4.5 cm. However, the compression and the ultimate bearing capacity vary little when the diameter of the piles changes from 7.0 cm to 8.0 cm. Moreover, the cracks or damage appear at the bottom or top of these piles, and the crack resistance of the concrete pile is improved with the steel fiber. Based on the re-sults, some suggestions were proposed for the design of the steel fiber reinforced concrete pile.

关 键 词：钢纤维混凝土桩 承载力 应变 破坏现象 

分 类 号：TU473[建筑科学—结构工程]