Monitoring On Field Of High Rock Slopes And Their Stability Research

The advanced monitoring, the limited equilibrium method and the numerical simulation are applied to study the high rock slopes of super bridge in Weijiazhou which has two tunnels to be dug at the top and two foundation pits of piers to be excavated on the hillside. Study on deformation tendency, steady condition, damage mechanism and damage pattern, the effect of anchor rope on the slope are presented. The major results are as follows:1. The general damage pattern of the bedding rock slope and the specific damage pattern of slope in Weijiazhou based on its engineering geology are analyzed.2. Based on the theoretical analysis and the research on damage pattern, Weijiazhou slope's stability is evaluated by the limited equilibrium method. The result shows that factor of safety(FS) is 1.133 in natural condition and is only 0.977 by VII earthquake;As 2# foundation pits of piers and tunnels been excavated, some damages happens in the unloading zone and the 2# foundation pits of piers;FS is 1.294 after the anchor ropes are fixed in the slope, thus proved that anchor rope is actually in favor of the stability of slope.3. After the monitoring system was established in Weijiazhou bridge slope, the surface and deep displacements and the loss of stress in anchor rope are measured. According to the obtained data, the deformation feature of rock body and the damage pattern of the slope have been discussed in detail. Finally, the rules of slope deformation are given.4. The stress distribution in Weijiazhou slope is analyzed by a FLAC3D numerical model. Under the role of gravity, the compressive stress and tensile stress appeared at the bottom of slope and on the surface of slope, respectively, especially the top of tunnels and the foot of the slope where stress concentration exists. If a load is applied on the slope, some results are obtained, including:â‘  the slope surface have a large tensile stress which may result in the damage of the 2# foundation pits of piers.â‘¡ the maximum unbalanced force shows that the stress will be redistribute after the load is applied.â‘¢ the displacement along Z axis is larger than that along X, Y axis after the load is applied.â‘£ the deep displacement near 2# foundation pits of piers and the surfacedisplacement under the tunnels are larger than the other zones.