基于质量检测与安全监测数据的补强拱坝弹性模量反馈

针对施工期进行补强加固处理的高拱坝在长期服役后真实材料力学参数是否满足设计要求的问题,本文依托某施工期补强碾压混凝土拱坝工程,首先采用钻孔取芯、大坝弹性波CT及表面波法(SASW)和现场普查相结合的方法进行大坝混凝土质量检测;进而基于变形监测资料对拱坝的实测位移进行定性分析;然后通过建立径向位移统计模型进行定量分析;接着采用正交设计-BP神经网络-数值计算相结合的方法,优化反演坝体和坝基的弹性模量。研究表明:该补强拱坝坝体内部混凝土强度基本在30 MPa以上,反演获得的坝体混凝土弹性模量为30.13～33.30 GPa。虽然该补强大坝拱冠梁处测点变形偏大且存在左、右岸变形不对称的现象,但结合运行期大坝质量检测成果以及参数反演结果,可认为目前补强拱坝运行状态良好,坝体混凝土能满足设计要求。

Elastic modulus feedback of reinforced arch dam based on quality inspection and safety monitoring data

In view of the problem of whether the actual material mechanical parameters of the high arch dam that''s reinforced during the construction period can meet the design requirements after long-term service, this paper, based on a reinforced RCC arch dam during the construction period, uses a combination of the methods of core drilling, elastic wave CT of dam, surface wave method (SASW) and field survey to detect the quality of dam concrete. Then,the measured displacement of the arch dam is qualitatively analyzed based on the deformation monitoring data. Next,the statistical model of the radial displacement is established to perform quantitative analysis. Subsequently, orthogonal design, BP neural network, and a numerical calculation method are combined to invert the elastic modulus of dam body and dam foundation. The results show that the strength of the concrete in the arch dam is more than 30MPa, and the elastic modulus of the concrete obtained by inversion is 30.13~33.30 GPa. Although the deformation of the measuring points at the arch crown beam of the arch dam is large and the deformation of the left and right banks is asymmetric, by combining with the dam quality inspection results and parameter inversion results, it can be concluded that the current operation state of the arch dam is good, the dam concrete can meet the design requirements.