阳江沥青混凝土心墙堆石坝应力变形特性研究

Research of stress and deformation characteristics of Yangjiang asphalt concrete core rockfill dam

为了评价阳江抽水蓄能电站下水库沥青混凝土心墙堆石坝的安全性,采用非线性有限元法对覆盖层最厚的大坝断面开展应力变形计算,详细模拟大坝的施工和蓄水过程。计算结果表明:竣工期和蓄水期坝体应力变形分布规律总体合理,竣工期坝体水平位移极值分别为-22.74 cm和26.18 cm,沉降极值为-73.80 cm,沉降率为0.91%。蓄水后,坝体水平变形变化较为明显,沉降极值稍有增加;坝体大、小主应力极值分别约为1.30 MPa和0.63 MPa,位于坝基全风化层。蓄水期,心墙挠度变化范围为73.76~77.83 cm。蓄水前后,心墙大、小主应力小幅变化,均为压应力,应力水平均较小,极值为0.68,心墙不会出现剪切破坏。总体上,大坝应力变形在正常范围内,整体安全性高,大坝断面设计合理。

In order to evaluate the safety of the electronic asphalt concrete core rockfill dam of Yangjiang Pumped Storage Power Station,the nonlinear finite element method was used to calculate the stress and deformation of the dam section with the largest overburden.The construction and water storage process of the dam were simulated in detail.The calculation shows that the distribution law of stress and deformation of the dam body in the completion period and water storage period is generally reasonable.The extreme values of horizontal displacements and settlement of the dam body in the completion period are-22.74 cm,26.18 cm,and-73.80 cm,respectively,and the corresponding settlement rate is 0.91%.After impoundment,the horizontal deformation of the dam body changes significantly,and the extreme value of settlement increases slightly.The corresponding extreme values of major and minor principal stresses of the dam body are about 1.30 MPa and 0.63 MPa,respectively,which are located in the fully weathered layer of the dam foundation.The settlement deformation of the core wall caused by water storage is very small.During water storage period,the deflection range of core wall is 73.76~77.83 cm.Before and after water storage,the major and minor principal stresses of the core wall changed slightly,all of which were compressive stresses,and the stress levels were small,with the extreme value of 0.68,and the core wall would not be damaged by shear.On the whole,the stress and deformation of the dam are within the normal range,the overall safety is high,and the dam section design is reasonable.