摘要
某水库工程拟在进行堆石料和过渡料填筑后再挖槽浇筑混凝土心墙。由于混凝土心墙高度达47.5 m,心墙与周围土体的协调变位,以及蓄水后心墙内力分布是工程关注的问题。对5种不同刚度材料的心墙应力应变特征计算分析表明:不同材料心墙的最大沉降均出现在坝体中部高程附近,最大沉降量约-18.909 cm(占坝高40.5 m的0.467%)。柔性好的塑性混凝土与坝体协调变位最好,刚性混凝土C25心墙的坝体与心墙变形协调性最差。坝体及心墙应力极值随心墙模量降低而降低。刚性最大的C25心墙在覆盖层和基岩交界处应力值超标,拉应力最大值达到-6.0 MPa,呈现出显著的悬臂效应;而塑性混凝土变形协调性良好,心墙上下游面拉应力均小于-0.5 MPa,应力水平也最优。建议设计施工优先采用塑性混凝土方案,而若要采用C25混凝土作为心墙材料,则需要对心墙做好配筋设计。
A project is proposed to excavate a channel and develop a concrete core wall with filling the rock-fill and transition material.As the height of concrete core wall reaches 47.5 m,the harmonic displacement of the core wall with the surrounding soil and the internal force distribution of the core wall is of great concern of the project.The calculation and analysis of the stress and strain of five different concrete core walls show that the maximum subsidence appears in the middle of the dam height,which is about 18.909 cm（0.467% of the dam height）.The results show that plastic concrete has the best flexibility to deform harmonically with the dam.And the dam with rigid C25 concrete core wall presents the worst deformation coordination.The stress decreases as the modulus of the core wall reduces.Tensile stress of the core wall exceeds standard requirement in many places near the juncture and the bedrock when C25 is used as core wall.In this case,the maximum tensile stress is-6.0 MPa,showing significant cantilever effect.If plastic concrete is adopted as core wall,the deformation and stress distribution is much better,and the tensile stress of upstream and downstream faces of the core wall is less than-0.5 MPa.So the plastic concrete construction scheme is strongly recommended,and if the scheme of C25 concrete core material is used,core wall reinforcement is essential.
出处
《水利与建筑工程学报》
2016年第3期59-64,112,共7页
Journal of Water Resources and Architectural Engineering
关键词
塑性混凝土心墙
非线性有限元
应力应变
应力水平
plastic concrete core wall
nonlinear finite element
stress and strain
stress level
