钻芯法检测薄壁预制构件混凝土抗压强度的试验研究  

Experimental research on concrete compressive strength of thin-walled precast component by core drilling method

作　　者：李雪雪 孙彬 毛诗洋 张晋峰 LI Xuexue;SUN Bin;MAO Shiyang;ZHANG Jinfeng(China Academy of Building Research,Beijing 100013,China)

机构地区：[1]中国建筑科学研究院有限公司,北京100013

出　　处：《建筑结构》2023年第24期74-79,共6页Building Structure

基　　金：中国建筑科学研究院有限公司青年科研基金资助(20200112331030033)。

摘　　要：为解决薄壁预制构件混凝土强度检测的技术难题,考虑到薄壁构件厚度一般不大于70mm,设计制作DH50(直径50mm、高度50mm)、D70H50(直径70mm、高度50mm)和DH100(直径100mm、高度100mm)三种芯样试件,开展钻芯法检测混凝土抗压强度的试验研究。结果表明:DH50芯样试件和DH100标准芯样试件均呈两端锥角为50°左右正倒相接的圆锥体破坏形态,而D70H50芯样试件两端锥角接近80°;小尺寸芯样试件和DH100标准芯样试件的抗压强度值均服从正态分布;D70H50芯样试件较DH50芯样试件、DH100标准芯样试件的抗压强度高,且其抗压强度离散性最小;基于最小二乘法建立的小尺寸芯样试件与DH100标准芯样试件的抗压强度换算关系具有较好的线性相关性。通过模拟抽样方法,研究确定了DH50、D70H50芯样试件的最小合理取样数量;综合考虑拟合效果和取样经济性,建议钻取高径比小于1的D70H50芯样试件检测薄壁预制构件的混凝土抗压强度。In order to solve the technical problem of concrete strength detection of thin-walled precast component,considering that the thickness of thin-walled component is generally no more than 70mm,three kinds of core samples about DH50(diameter 50mm,height 50mm),D70H50(diameter 70mm,height 50mm)and DH100(diameter 100mm,height 100 mm)were designed and manufactured.The experimental research on the detection of concrete compressive strength by core drilling method was carried out.The results show that both DH50 core sample and DH100 standard core sample are in the form of cone failure with a cone angle of about 50°at both ends,while the cone angle of D70H50 core sample is close to 80°.The compressive strength of small-size core sample and DH100 standard core sample obey normal distribution.The compressive strength of D70H50 core sample is highest than that of DH50 core sample and DH100 standard core sample,and its compressive strength dispersion is the smallest.The compressive strength conversion relationship between small-size core sample and DH100 core sample established based on the least square method has a good linear correlation.Through the simulation sampling method,the minimum reasonable sampling quantity of DH50 and D70H50 core sample was determined.Comprehensively considering the fitting effect and sampling economy,it is recommended to drill D70H50 core sample with height diameter ratio less than 1 to detect the concrete compressive strength of thin-walled precast component.

关 键 词：薄壁预制构件 钻芯法 混凝土抗压强度 换算关系 取样数量 

分 类 号：TU375[建筑科学—结构工程]