大坝观测中测点处混凝土的应变重分布  

Strain Re-distribution near Measuring Point in Dam Observation

作　　者：陈灿明[1,2] 黄卫兰[1,2] 唐崇钊[1,2] 张大伟[1,2] 

机构地区：[1]南京水利科学研究院,江苏南京210029 [2]水利部水科学与水工程重点实验室,江苏南京210029

出　　处：《中国水能及电气化》2010年第5期41-45,共5页China Water Power & Electrification

摘　　要：用湿筛法剔除混凝土部分粗骨料,湿筛后混凝土徐变增加,弹模有所降低,因而大坝应变观测中测点局部位置混凝土与周围原级配混凝土之间成为非均质变形特征的粘-弹性联体,将引起应变和应力的重分布(或调整),实测应变可能不能真实反映原级配混凝土的应变。本文首先讨论了混凝土徐变和弹性模量湿筛前、后关系的现有试验成果及其量值变化,再以大平面体内嵌入一个异性圆核为模型,分析两种非均质线粘-弹性联体圆内(应变测点位置)的应变重分布,并提出作应力应变分析时应依据灰浆率比和弹性模量比对应变观测值作相应的调整或修正。In dam observation, coarse aggregate is sieved out near measuring point. When coarse aggregate is removed by wet sieving, concrete creep increases while elastic modulus decreases. In this case, it is assumed as non-homogeneous viscoelastic compound and it causes strain and stress re-distribution. Therefore, the observed value can not response the strain of the dam. In this paper, the present outcomes of concrete creep and elastic modulus before and after wet sieving are discussed. Then, a model, a pellet is embedded in the big plane, is established to analyze the strain re-distribution in non-homogeneous viscoelastic compound. It is pointed out that the measured value should be adjusted and revised according to mortar rate and elastic modulus ratio in stress and strain analysis.

关 键 词：湿筛混凝土 徐变比 应变重分布 

分 类 号：TV698.11[水利工程—水利水电工程]