基于破坏模式的长芯劲性搅拌桩竖向承载力计算方法研究  

Study on Calculation Method of Vertical Bearing Capacity of Long Core Strength Mixing Pile Based on Failure Mode

作　　者：程博华[1] 

机构地区：[1]中国铁建股份有限公司,北京100855

出　　处：《铁道建筑技术》2016年第6期102-106,共5页Railway Construction Technology

摘　　要：长芯劲性搅拌桩是一种钢筋混凝土预制桩长大于水泥土搅拌桩的新型劲性复合桩。鉴于该桩型的应用正处于起步阶段,现有规程中竖向承载力的计算方法各有不同,本文对其进行了综合分析,并提出了一种基于破坏模式的单桩竖向承载力计算方法,后应用工程实例加以验证。结果表明:单桩竖向承载力需依据该桩型的三种破坏模式进行选取;考虑复合段桩端阻力对承载力的贡献,会使计算结果明显大于实测值,造成安全隐患;未考虑复合段的挤土效应,会使侧摩阻力调整系数取值偏小,忽略部分侧摩阻力对承载力的贡献,导致设计保守。Long core strength mixing pile is a new type of strength composite pile which reinforced concrete precast pile is longer than cement mixing pile. Because this kind of pile is in its infancy and the calculations of vertical bearing capacity of single pile failure mode in existing industry specifications are different, comprehensive analysis was conducted and a calcu- lation of vertical bearing capacity of single pile which was based on three failure modes was proposed, and verified by prac- tical engineering. The main results showed that vertical bearing capacity of single pile should be selected according to its failure mode; the calculation value would be larger than the measured value if considering the effect of pile tip resistance of composite sections which may cause potential safety hazard. The coefficient of the lateral friction would be relatively small and the contribution of lateral friction to the capacity would be partly ignored if not considering squeezing effect, which may cause over-designed.

关 键 词：长芯劲性搅拌桩 竖向承载力 破坏模式 

分 类 号：TU411[建筑科学—岩土工程]