纳子峡大坝面板服役性能分析及稳定性评价

Service performance analysis and stability evaluation of concrete face slab of Nazixia Dam

为掌握纳子峡纤维素纤维混凝土面板堆石坝在服役期间面板的工作情况,在面板上布置了监测设备,分析了纤维素纤维混凝土面板在2015年1月—2017年1月间温度、应力、应变的监测数据。结果表明:高程3116.18 m以上的测点测值整体较小且受外界气候影响较大,故测点处温度、应力、应变测值变幅较大;高程3116.18 m以下的测点测值整体较大且受外界气候影响较小,故测点处温度、应力、应变测值变幅较小;面板混凝土对寒冷气候的适应性较强,2016年1月21日青海门源6.4级地震对面板工作性能影响不显著。纤维素纤维的掺入能够提高混凝土在高海拔严寒气候下的服役性能,使面板能够保持稳定的工作状态,有利于大坝的安全稳定。

In order to grasp the working condition of the slab of the Nazixia Dam of cellulose fiber concrete face rockfill during service,the monitoring equipment was arranged on it.The monitoring data of temperature,stress and strain change of cellulose fiber concrete face slab from January 2015 to January 2017 were analyzed.The analysis results show that the measured values of the elevation above 3116.18 m are smaller overall and greatly affected by the external climate.Therefore,the temperature,stress and strain measurements at these measuring points vary greatly.The measured values of the elevation below 3116.18 m are larger overall but less affected by the external climate.Therefore,the temperature,stress and strain measurements at these measuring points vary slightly.Slab concrete has strong adaptability to cold weather,and the 6.4-magnitude earthquake in Menyuan,Qinghai province on January 21,2016 has no significant influence on the working performance of the slab.The results show that the incorporation of cellulose fiber can improve the service performance of concrete in cold climate at high altitude,enable the slab to maintain a stable working condition.It indicates that the application of cellulose fiber concrete is beneficial to the safety and stability of the dam.