多层混凝土结构仿真应力分析的并层算法

Mixed-layer Method for Analysis of Stresses by Simu lating the Construction Process of Multilayered High Concrete Structures

混凝土坝等常分层施工，各层的弹性模量，徐变度和温度都不同，仿真应力分析必须分层进行计算，但混凝土坝常包含几十层甚至一、二百层，使分层计算非常困难。本文提出并层算法，根据混凝土变形特性与龄期的关系，把混凝土坝分为几个区域。上部几层是分层计算的，下部根据混凝土龄期的不同而逐步把几个浇筑展合并起来，使原来的一、二百层，减少到十层左右，计算工作得到极大的简化，但每一个浇筑层都经过了从单层计算到并层计算的全过程，计算中已充分考虑了分层施工的实际影响。本文所提方法，使得按混凝土高坝分层施工实际情况用有限元法进行仿真应力分析成为实际可行的，因而具有较大实用价值。本文给出了并层后的应力计算方法。

The mass concrete structures, such as concrete dams, are constructed layer by layer.The modulus of elasticity, the unit creep and theadiabatic temperatu re rise are differen t tror each layer. In order to simulate the construction process of tile structure, the structure must beanalyzed layer by layer to compute the construction stresses in it. Asthere are 50--200 layers or more in a high concrete dam, it is really verydifficult to co-mpute the stresses in these structures by the finite element method .The mixed layer method is proposed in this paper.Accordingto the relation between the deformation and age of concrete, the structure is divided into several regions. The 2--3 layers in the upper part ofthe structure are computed layer by layer. In the lower part, accordingto the age of coners Le, several layers are combined together, the originalstructure of 50-200 layers are Lransformed to a s Lructure of about 10layers. Thus the computation is simplified remarkably. Each layer hasundergone the whole process from a single layer to the mixed layer, theeffect of construction by layers are fully considered in the stress analysis. Due to this method, it is possible to compute the stresses in a highconcrete structure by simulating the layer by layer construction process. An example is given in this paper for computing the stresses in thestructures after combining of layers.