不同显色试剂测量混凝土碳化深度的研究  

Study of concrete carbonation depth measured by using different color reagents

作　　者：宋守波 朱国飞[1] 崔宏志[1] 

机构地区：[1]深圳大学土木工程学院,广东深圳518060

出　　处：《混凝土》2016年第7期142-144,148,共4页Concrete

摘　　要：目前的国家规范中,用酚酞试剂测量混凝土的碳化深度,但是这种方法不能很好地表征出混凝土的部分碳化区。另外,已有的用于预测混凝土碳化深度的碳化模型正处于不断发展和完善中。鉴于上述背景,本研究中用显色p H值不同的百里酚酞试剂、p H试剂、酚酞试剂分别测量混凝土3、7、14、28、56 d五个碳化龄期的碳化深度。研究发现:不同显色p H值的试剂测得的碳化深度存在较大差异,显色p H值越高的试剂,用其测得的碳化深度值越大;从保护钢筋角度,酚酞试剂作为常用检测试剂来测量混凝土碳化深度结果偏小;碳化的混凝土存在部分碳化区,利用不同试剂测量的碳化深度相减,可以近似地得到混凝土部分碳化区的大小;三种试剂测得的碳化深度值与碳化龄期的平方根成正比关系,与混凝土碳化深度预测模型D_c=Kt^(1/2)基本一致,但预测模型的K值不同。In the current national standard,carbonation depth of concrete is measured by using phenolphthalein reagent,but this method can not characterize the partly carbonated zone of carbonated concrete well.In addition,the carbonation depth models for predicting car-bonation depth are in the state of development and improvement continuously.In view of the above background,after five different peri-ods′carbonation including 3,7,14,28,56 days,carbonation depth of concrete was measured by using thymolphthalein reagent,pH reagent and phenolphthalein reagent,these reagents having different value of color pH.The study show that carbonation depth of concrete measured by using different reagents that have different value of color pH exists large difference,the higher value of color pH of the reagent with the bigger value of measured carbonation depth.From the perspective of protecting rebar,phenolphthalein reagent used as a commonly detec-tion reagent to measure concrete carbonation depth,the result is smaller.The partly carbonated zone of carbonated concrete is existed,and the size of partly carbonated zone can be gotten approximately by using subtraction of carbonation depths measured by using different reagents.Carbonation depth of concrete measured by using three reagents is proportional to the square root of the carbonization age,and it approximately agrees with the prediction modelDc=K√tof carbonation depth of carbonated concrete,but with different values ofKof prediction model for each reagent.

关 键 词：混凝土碳化深度 显色试剂 部分碳化区 碳化深度预测模型 

分 类 号：TU528.07[建筑科学—建筑技术科学]