大体积混凝土温度裂缝扩展过程模拟

大体积混凝土的温度裂缝是关系到水电工程中混凝土大坝安全的重要问题，它贯穿混凝土坝的施工期直至运行期。重点探讨了应用无网格法求解大体积混凝土温度裂缝扩展过程的模拟方法。无网格法采用节点来离散求解域，特别适用于裂缝开裂过程的模拟。结合混凝土热传导问题推导了伽辽金无网格方法控制方程和基本算法步骤，编制了混凝土温度场计算和温度裂缝扩展过程模拟的无网格法程序，通过具体的算例验证了所编制的伽辽金无网格程序的正确性。数值算例的计算结果表明，无网格法能够有效地模拟混凝土块在温度应力作用下的开裂发展过程，计算结果符合大体积混凝土块在均匀温降和基础强约束条件下的裂缝分布规律。

Simulation of mass concrete temperature cracking propagation process

Mass concrete temperature cracking is an important problem of concrete dam safety in hydropower projects, which exists from construction process of concrete dam to operation period. This paper introduces the simulation method of mass concrete temperature cracking propagation process by element-free Galerkin method(EFGM). Due to its no-remeshing property, EFGM is very suitable for cracking problem. The governing equation of EFGM is presented for concrete heat conduction problem. It is discussed how concrete cracking process brought from temperature decrease is simulated by EFGM. The algorithm process is also presented. Then a numerical simulating program is developed; and an example including an initial crack is computed to validate the program. Result shows good accuracy and reliability of this method; and concrete cracking process brought from temperature decrease may be simulated effectively by EFGM. The cracking propagation process of concrete block accords with general crack distribution rule.