应力反射波在注浆微型钢管桩中的波速研究  

Behaviour of the Wave Velocity during Low-strain Integrity Test for Grouting Micro-steel-pipe Pile

作　　者：何忠意 朱佩宁 周亚东 齐昌广[3] HE Zhongyi;ZHU Peining;ZHOU Yadong;QI Changguang(Guangdong Tianxin Electric Power Engineering Testing Co.,L td.,Guangzhou 510663,China;School of Civil Engineering,Tianjin Chengjian University,Tianjin 300384,China;Faculty of Architectural,Civil Engineering and Environment,Ningbo University,Ningbo 315211,China)

机构地区：[1]广东天信电力工程检测有限公司,广东广州510663 [2]天津城建大学土木工程学院,天津300384 [3]宁波大学建筑工程与环境学院,浙江宁波315211

出　　处：《防灾减灾工程学报》2020年第1期9-17,共9页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(51508282);浙江省自然科学基金青年基金项目(LY18E080010);天津市自然科学基金项目(18JCYBJC22600)资助。

摘　　要：基于三维波动理论,考虑对长细比较大的注浆微型钢管桩(GMSP桩)满足一维弹性杆件条件,对应力反射波运动方程进行简化分析;利用材料对强冲荷载的动态响应研究成果,结合物质运动学LOVE方程及弹性力学ST.Venant原理,推导出低应变法反射波在GMSP桩注浆体与钢管共同组成的复合胶结体中的传播波速理论计算模型;设计及开展了三个不同地质条件场地的9条试桩低应变反射波试验;并对现场试验与理论模型计算波速进行对比与分析,得出以下结论:GMSP桩完整性可采用低应变动测检测;文中提出的理论模型计算波速与现场实测波速吻合度高,相对可靠性、准确性。建议在GMSP桩工程桩进行低应变应力反射波检测时,可结合提出的理论计算模型,先对其低应变波速进行计算,以此对桩长、缺陷位置以及完整性进行判定。A motion equation of stress reflection wave,based on three-dimensional wave theory,was proposed in this paper to provide insight into the low-strain integrity behaviour of grouting Micro-steelpipe with large slenderness ratio which satisfy the one-dimensional elastic member condition.This new analytical solution can be used to calculate the propagation velocity of the reflected waves in the composite cementation composed of the cement grouting and steel tube in GMvSP pile.This analytical solutions have advantage of previous research results in dynamic response of materials to strong impact loads,which combines with the LOVE equation of material kinematics and the ST.Venant principle of elasticity.Three low-strain reflected wave tests for nine piles under different geological conditions have been conducted to examine the behaviour of low-strain integrity of GMSP pile.And then,the analytical solution were validated against field tests,with good agreement obtained.Following conclusions are drawn:(i)the integrity of GMSP pile can be tested by low-strain integrity test;(ii)the calculated wave velocity by this new analytical solution proposed in this paper coincides with measured wave velocity,which proved that it is relatively reliable and accurate.It is suggested that,in the detection of engineering piles by the low-strain integrity test,the wave velocity can be calculated firstly through this new analytical solution.And,this new analytical solution,can provide guidance for low-strain integrity test of GMSP pile,which can determine and analyze the length,defect location and then estimate the integrity of GMSP pile.

关 键 词：注浆微型钢管桩 波动理论 桩身完整性 低应变反射波法 波速理论计算模型 

分 类 号：TU443[建筑科学—岩土工程]