钢管-桩心配筋微型桩极限抗弯承载力研究

Study on Ultimate Flexural Bearing Capacity of Mini Pile Featuring Steel Tube and Centered Steel Bar

钢管-桩心配筋微型桩是在微型钢管桩的基础上加入桩心钢筋组合而成。对钢管-桩心配筋微型桩进行了室内极限抗弯承载力试验。结果表明:随着弯矩增大,试件中性轴往受压侧移动,承载力不断提高;设计时应考虑桩心钢筋对抗弯承载力的贡献;钢管-桩心配筋微型桩试件在纯弯矩作用下表现出较好的延性。与无桩心配筋的微型钢管桩极限抗弯承载力对比后发现,桩心钢筋的存在使得钢管-桩心配筋微型桩极限抗弯承载力提高了50%,可在工程中推广应用。

The mini pile featuring steel tube and centered steel bar is on the basis of mini steel tube pile to add centered steel bar.Through the indoor ultimate flexural bearing capacity test of mini pile featuring steel tube and centered steel bar,it is concluded that with the increase of bending moment,the neutral axis of the specimen moves to the compressive side,and the bearing capacity increases continuously.The contribution of the centered steel bar to the flexural bearing capacity should be considered in the design.The results show that the specimen of steel tube and centered steel bar pile under pure bending moment is showing good ductility performance.Comparing the experimental results with the ultimate flexural bearing capacity of mini steel tube pile,it is found that the existence of centered steel bar makes the ultimate flexural bearing capacity of steel tube and centered steel bar pile increases by 50%on the basis of mini steel tube pile,which can be popularized and applied in engineering.