Research On Construction Process In The Simulation Of Concrete Structures’ Thermal Stress

Water conservancy construction is an important means in the reasonable development of water resources, and concrete plays an important role in the water conservancy construction and hydropower projects. Temperature has a significantly influence on the mass concrete structures’stress field during construction period. In order to ensure the safe and efficient operation of the water conservancy projects, simulating thermal stress field of the massive concrete structures is significant.Simulating temperature field and thermal stress field of the massive concrete structures during construction period with finite element method, take into account the casting billet layer. By calculating the temperature field and thermal stress field under different conditions of casting billet thickness and casting billet interval, their effect will be reflected.The results show that casting billet layer has a remarkable influence on temperature field and thermal stress field. Especially for the thermal stress field, the stress has a big change after considering the casting billet layer. The results also show that the hydration speed of concrete decided the heat transfer of casting billet layer. For n is small (n represents age of hydration heat of concrete reaction half), the max temperature decreased as casting billet interval increased and increased as casting billet thickness increased, and the maximum tensile stress decreased as casting billet interval increased and increased as casting billet thickness increased. For n is large, the max temperature increased as casting billet interval increased and decreased as casting billet thickness increased. The maximum tensile stress increased as casting billet thickness increased, and, in some cases,it first increased and then decreasesd as casting billet interval increased, in other cases, it always increased as casting billet interval increased.At present, as casting billet layer is not consider in the simulation of thermal stress field of the massive concrete structures, there are some differences between theoretical results and practical results. The results of simulation calculations that considering casting billet layer show that casting billet layer has a remarkable influence on thermal stress field under some cases. In these cases, casting billet layer should be considered in simulation model. In other cases, casting billet layer could be ignored in simulation model.