泥质灰砂岩地质条件下低应变检测摩擦桩桩身完整性为Ⅰ、Ⅱ类的判定方法研究  

Research on the Method for Evaluating the Integrity of Friction Piles Using Low-strain Testing in Muddy Lime Stone Geological Conditions

作　　者：孙巍 彭亚 吴汉 钱海龙 刘翔 Sun Wei;Peng Ya;Wu Han;Qian Hailong;Liu Xiang(Jiangxi Huaheng Engineering Testing Co.Ltd.,Nanchang,Jiangxi 330001)

机构地区：[1]江西华恒工程检测有限公司,江西南昌330001

出　　处：《江西建材》2024年第11期255-259,共5页

摘　　要：在低应变反射波法中,桩底反射信号的取得与否是桩身质量评判的一个重要判据。若测桩波形中没有明显的桩底反射信号,根据现行规范很难判别Ⅰ、Ⅱ类桩,也无法确定桩长是否达到设计要求。通过对桩身阻抗和岩体阻抗差异变化下桩底反射的特征和泥质灰砂岩与混凝土结合面的反应机制的理论研究,同时结合低应变法与钻芯法、声波透射法的判定结果比对,提出了在桩身阻抗和岩体阻抗差异不大条件下低应变法判定Ⅰ、Ⅱ类桩的方法和流程。该判定方法在浙西地区泥质灰砂岩地质条件下对检测单位桩检工作以及施工单位了解基桩的施工质量均有指导作用。In the low strain reflected wave method,obtaining the reflected signals of the pile bottom or not is an important criterion to judge the quality of the pile.However,If there are no obvious pile bottom reflected signals in the measured pile waveform,it is difficult to differentiate between Class I and II piles according to current standards,and it is also impossible to determine whether the pile length meets the design specification.This paper presents a theoretical study on the characteristics of pile bottom reflection under varying pile shaft and rock mass impedance differences,as well as the reaction mechanisms at the interface between muddy limestone and concrete.A method and procedure for determining Class I and II piles using the low-strain method under conditions of small differences in pile shaft and rock mass impedance are proposed by comparing the results of the low-strain method with those of the drilling core method and the ultrasonic transmission method.This determination method has guiding significance for pile inspection work by testing units and for construction units to understand the construction quality of foundation piles in the geological conditions of muddy limestone in western Zhejiang province.

关 键 词：低应变 桩底反射 泥质灰砂岩 桩身完整性 

分 类 号：TU195[建筑科学—建筑理论]