3-D FEM Analysis On Temperature Field And Thermal Creep Stresses Field In The Masonry Arc Dam

There are some advantages using masonary arc dam, that is obtaining raw materials locally, coming through flood period easily, construction simply, saving investment and having good safety feature. So the local material dam has been widely promoted in the course of dam construction. The construction ways of one storey pouring and rising wholly generally are used during the masonry arch dam construction. Masonry arch dam forms the whole promptly after each level finished and doesn't have a clear closure position and closure temperature. The big thermal stresses which build up in the construction period will have great impact on the stresses in the operating period. It is necessary to simulate and analyse the thermal stresses caused by constructionFocusing on some problems in thermal stress simulation analysis on masonry arc dam, adopting 3-D FEM models, some research works have been done as follows:1. Hydration heat of cement is a major force in the development of thermal stresses in the course of construction. Changes in temperature prick up the thermal stresses in the dam. Thermal stresses may pull apart masonry joint of stone masonry structure and even lead to through crack in the mass of dam. And so it threatens to stabilization and safety of dam.2. Thermal field and thermal creep stress field were made of masonry arc dam by 3-D FEM. It is difficult to deal with complicated heat radiating boundary conditions during the simulation analysis. The paper introduced a method that can find heat radiating boundary automatically during different stages of construction.3. How to chose material parameter directly affect the result of calculation. Soffit materials of pea gravel concrete is mixtintite of pea concrete and stone. The paper use equivalent elastic modulus to denote soffit mixtintite materials.4. In this paper, encrypting mesh programme was complied to partition surface rag mesh for Shuangkoudu Masonry Arc Dam and encrypt the mesh of imbankment. Compatible displacement method of different mesh was applied to solve incompatible mesh of dam basement and imbankment.5. Based on the practical project Shuangkoudu Masonry Arc Dam, the dam's construction process was simulated by a small time step,0.5 or 1 days. The environmental temperature change, hydration heat rise, creep, and other implementation details were all considered. The simulation of thermal stresses for masonry arc dam was accomplished for the first time. The characteristics of temperature and stesses in masonry arc dam with sequence construction were studied. The research results are valuable for designers to choose the optimum construction schedule to decrease the thermal stresses.