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郑秀培(水利电力部昆明勘测设计院):原文具有很大的理论与实用价值,文中的优点很多,与几种比较典型的方法比较,全面和周密的考虑了各种因素的影响,推理清楚明了,便于掌握,而且应用范围甚广,学习后有下述二点想法.(一)根据原文的分析法,在计算时假定外荷载是集中作用在每个格栅的结点上,代用格栅的分格便不宜过稀,否则会影响计算的精度,特别是想用原文式(88)至(95)直接计算内力和应力时尤甚,同时格栅分格过稀,也不宜于详细了解坝体和壳体各部分的应力分布,将格栅分格密一些则能解决上述存在的问题,但将加大计算的工作量,我想用类似于差分网格法的方法,将格栅相对分密一些,每一结点用三个线变位未知数代替原文的五个变位未知数(三个线变位和二个角变位),即将原文的二个角变位,分别用径向位移一次偏导数的有限差分公式表示,并从平衡方程中消去二个角变位未知数,得出三组表示三个线变位的线性方程,这三组方程和某些用壳体理论得到的差分方程相类似,但却包含了原文所全面考虑到的各种因素,这样似有助于问题的简化,今分述如
Zheng Xiupei (Ministry of Water Conservancy and Electric Power Kunming Institute of Surveying and Design): The original text has great theoretical and practical value. The advantages in the text are many. Compared with several typical methods, comprehensive and careful consideration of the influence of various factors makes the reasoning clear , Easy to grasp, and a wide range of applications, after learning the following two ideas. (A) According to the original analysis method, in the calculation assume that the external load is concentrated on each node of the grille, substitute grille The sub-grid should not be too dilute, otherwise it will affect the accuracy of the calculation, especially when you want to directly calculate the internal forces and stress using the original formulas (88) to (95). At the same time, the grid grid is too thin to be understood in detail. The stress distribution of various parts of the dam body and the shell, which can be used to solve the existing problems mentioned above, will increase the workload of calculations. I would like to use a method similar to the differential mesh method to put the grid. Relatively dense, each node replaces the five unknowns of the original text (three line displacements and two angular displacements) with the three line displacement unknowns, that is, the two corners of the original text are shifted, respectively. The finite difference formula for the first-order partial derivative of the displacement is expressed and the equilibrium equation In the elimination of the two corners of the unknown, we obtain three sets of linear equations that represent three line displacements. These three sets of equations are similar to some of the difference equations obtained using the shell theory, but they contain the full consideration of the original text. Various factors, this seems to help simplify the problem.