三峡茅坪溪防护坝沥青混凝土心墙变形监测

Deformation monitoring on asphalt concrete core wall of TGP's protection dam for Maoping brook valley

在对茅坪溪防护坝施工期沥青混凝土心墙进行安全监测时 ,对心墙应变、应力、变形及温度状态等观测资料进行了较详细的分析探讨。目前监测结果为 :心墙底部压应力测值增长与心墙高程升高关系协调。心墙不同高程处的应变主要受温度、上部荷载及两侧过渡料性质影响 ,从测值分析 ,心墙中上部应变随高程升高其值增长较快。心墙与过渡料间位错变形为 -0 .3 2～ -3 2 .95mm ,反映心墙压缩变形大于两侧过渡料沉降变形 ,且心墙中部变形较上下部变形要大。底部心墙与基座间水平变形为 -1.85～ 17.89mm ,变形初期主要受施工影响 ,后期施工对其影响较小 ,总体变形稳定。分析表明心墙现阶段变形稳定 。

In the process of safety monitoring on asphalt concrete core wall of TGP's protection dam for Maopingxi brook valley during construction period, the thorough analysis and discussion were carried out on monitored data of the core wall, such as strain and stress, deformation and temperature etc. At present, the monitored results demonstrate that compressive stress at the core wall bottom increases well coordinately with top elevation increment of the core wall, the core wall strain at different elevation is mainly affected by temperature, upper loading and the material behavior in transitional zone on both sides, and the strain of the middle and upper core wall increases quickly with the uprising of the wall, the displacement deformation between the core wall and transitional material is -0.32～-32.95mm, reflecting that the compressive deformation of the core wall is larger than the settlement deformation of transitional material on both sides and the deformation of the middle core wall is larger than that of the upper and lower core wall, the horizontal displacement deformation between core wall bottom and foundation mat is -1.85～17.89mm, the early-stage deformation was mainly affected by construction, but later-stage construction imposed less influence on the deformation, in general, the deformation is stable. The analysis demonstrates that the present-stage core wall deformation is stable and in accordance with the general deformation law of earth rock dam.