混凝土中fCaO引起的体积安定性鉴定方法

Method for Concrete Volume Stability Determination due to f CaO

摘要:

结合检测实例介绍了混凝土中ｆＣａＯ 引起的体积安定性的两种鉴定方法．膨胀应力法：定量分析混凝土中残存的ｆＣａＯ，估测ｆＣａＯ水化产生的膨胀应力，比较膨胀应力与混凝土抗拉强度的大小，据此评定混凝土体积安定性；沸煮法：根据沸煮前后混凝土超声波声速、劈裂抗拉强度及混凝土薄切片的变化，评定混凝土体积安定性．

Abstract:

Two methods for concrete volume stability determination due to f CaO are introduced.One is the expansive stress analysis.In this method,the residual f CaO in concrete was analysed quantitatively,then the expansive stress due to f CaO hydration was deduced,finally,the tensile strength of concrete core was tested.If the expansive stress is smaller than the tensile strength,the stability of concrete will be fine.Another one is boiling method which is similar to the test method for cement stability.The concrete sample was boiled for several hours to accelerate f CaO hydration.The ultrasonic velocity of concrete sample before and after boiling was measured and the tensile strength of concrete core was tested.According to the difference of ultrasonic velocity before and after boiling,the volume stability of concrete can be determined.