摘要
输电铁塔桩基础上部开裂将影响其承载力和耐久性,针对某500 kV输电塔C腿基础上部开裂的实际问题,通过引入量化基础开裂演化过程的损伤因子,提出混凝土-钢筋网-地基土三维一体化建模方法,分别从基础受力状态和开裂状态验证了建模方法的合理性,考虑上拔荷载、水平荷载和纵筋配筋率,探究了基础开裂成因及开裂特性。结果表明:基础上部最先开裂部位为地脚螺栓处,而后向其周围及内部延伸;作用在基础上的上拔荷载为基础上部开裂主控因素,损伤因子随上拔荷载的增大而增大,当施加上拔荷载的比例达到设计荷载的95%时,损伤因子由前一级荷载下的0.28陡增至0.61;水平荷载和纵筋配筋率对基础开裂几乎没有影响,因此,治理输电塔基础上部开裂的关键部位是地脚螺栓处,关键指标是控制上拔荷载。
Cracking in the upper section of transmission tower pile foundations affects both its load-bearing capacity and durability.Addressing the issue of cracking in the upper section of the C-leg foundation of the 500 kV transmission tower,a three-dimensional integrated modeling method of concrete,reinforcing steel mesh,and foundation soil is proposed by introducing a damage factor to quantify the evolution of foundation cracking.The rationality of the modeling method is validated based on the foundation's stress state and cracking state.Uplift loading,horizontal loading,and longitudinal reinforcement ratios are considered to investigate the causes and characteristics of foundation cracking.The results show that the initial cracking occurs at the anchor bolts,and then extends around and inward.Uplift loading is identified as the main factor controlling cracking in the upper section of the foundation,with the damage factor increasing as uplift loading increases.When the proportion of applied uplift loading reaches 95%of the design load,the damage factor sharply increases from 0.28 under the previous load level to 0.61.Horizontal loading and longitudinal reinforcement ratios have minimal impact on foundation cracking.Therefore,the critical area for addressing cracking in the upper section of the transmission tower foundation is the anchor bolt location,and the key parameter is controlling uplift loading.
作者
朱耀中
刘俊红
夏远灿
胡应华
张鹏通
Zhu Yaozhong;Liu Junhong;Xia Yuancan;Hu Yinghua;Zhang Pengtong(Ultra High Voltage Branch,State Grid Chongqing Electric Power Company,Chongqing 400039,China)
出处
《科技通报》
2025年第6期106-111,共6页
Bulletin of Science and Technology
基金
国网重庆市电力公司科技项目(B1201324005C)。
关键词
输电塔桩基础
损伤因子
上拔荷载
开裂成因
transmission tower pile foundation
damage factor
uplift loading
causes of cracking
作者简介
朱耀中(1983-),男,湖北孝感,硕士研究生,高级工程师,研究方向为输电运检。E-mail:573987150@qq.com。
