The calculation of thermal stress and thermal crack propagation remains a tough problem for hydraulic structure engineering. Due to its node discretization and no-remeshing property, the EFGM (Element free Galerkin Method) is very suitable for simulating cracking problems. Based on the EFGM, the approach for calculating the thermal stress and thermal crack propagation is studied, and a diffraction method is presented to simulate the multi-line discontinuity as well as the contour integral method for SIFs (Stress Intensity Factors) calculation. Then a VC++ program is developed. Samples including a surface thermal shock problem, a straight side cracking plane problem and a slope side cracking plane problem are computed to validate the program. All results show good accuracy and reliability. Then taking a bottom-restrained concrete block suffering thermal stress as an example, the crack propagation is simulated by the proposed approach. Finally some key problems for crack propagation simulation are discussed.
