温度荷载是拱坝的主要设计荷载之一,与封拱温度、环境气温、库水水温等关系密切,实际温度荷载难免与设计温度荷载存在一定差异,传统点式温度计监测数据信息量少,难以进行合理有效的拱坝温度荷载反馈。结合溪洛渡特高拱坝典型坝段分布式光纤顺河向实测温度,基于矩法进行高拱坝实际温度荷载反馈,即采用多项式表示等效温度,根据等效温度的各阶矩与分布式光纤顺河向实测温度相应的各阶矩相等,确定多项式的系数,进而得到等效温度的分布。分析表明,现有规范采用的全截面线性化等效温度仅是非线性等效温度在一次矩等效时的特例,通过计算2阶和3阶矩等效温度,获得坝段截面非线性温度分布,更加全面反映高拱坝从封拱灌浆到水库正常运行期间坝体温度的调整过程,可为拱坝设计提供有益的技术补充。
Temperature load is one of the main design loads of the arch dam,which is closely related to closure grouting temperature and environment temperature and water temperature of reservoir. However,there are some differences between the actual temperature loads and the design temperature loads. As the traditional point thermometer monitoring data is far from enough,it is difficult to make reasonable and effective feedback of the arch dam temperature load. Combining with the measured temperature monitored by a distributed optical fiber placed on a typical dam section of the Xiluodu high arch dam,based on a moment method,the actual temperature load of the high arch dam got feedback. The equivalent temperature can be expressed by polynomial with the moment method.Based on the equivalence principle of moments of the equivalent temperature and the measured temperature given by the distributed optical fiber,the coefficients of the polynomial and distribution of the equivalent temperature can be obtained. Analysis results show that the whole cross-section of the equivalent linear temperature in the existing specifications is only a special case of the nonlinear equivalent temperature which is 1 moment. By calculating 2 and3 moments equivalent temperature of the actual temperature and obtaining the nonlinear temperature distribution of the dam sections,the adjustment process of the arch dam temperature from the closure grouting to the normal operation can be more fully understood,and it can provide a useful supplement to the arch dam design.