基于有限元的重力坝溢流坝段反弧段裂缝成因分析

Finite element-based analysis of the causes of cracks in the spillway crest curve section of gravity dam

本文主要采用数值模拟的方式,研究了广东省枫树坝水电站溢流坝段反弧段变电洞顶部裂缝成因。通过建立有限元模型,并依据实测数据和工程经验确定模拟参数,模拟了大坝常规运行期的温度场和应力场。研究表明,夏季高温导致大坝内外温差不同,在强结构约束下将产生最大2.64MPa的拉应力,超过抗拉强度是造成变电洞顶部深层裂缝的主要原因。模拟结果和实际观测到的裂缝位置一致,并与测缝计监测得到的裂缝开合度结果吻合。在今后的设计中,需考虑运行期温度应力的影响,避免产生贯穿性裂纹。

This paper primarily employs numerical simulation to investigate the causes of cracks at the top of the transformer tunnel in the spillway crest curve section of the Fengshuba Hydropower Station in Guangdong Province.By establishing a finite element model and determining simulation parameters based on measured data and engineering experience,the temperature field and stress field during the regular operation period of the dam were simulated.The study indicates that the temperature difference between the inside and outside of the dam during the hot summer season,coupled with strong structural constraints,results in a maximum tensile stress of up to 2.64MPa,exceeding the tensile strength.This is identified as the primary cause of deep-seated cracks at the top of the transformer tunnel.The simulation results align with the observed crack locations and are consistent with the crack opening and closing measurements obtained from crack monitors.In future designs,it is essential to consider the influence of temperature-induced stress during operation and to prevent the formation of through-thickness cracks.