注浆对岩体节理面加固作用的试验研究

Experimental study on the effect of grouting on the joint surface of rock mass

为了确定裂隙注浆后对围岩理化性质的影响,通过现场采样,制作了5个红砂岩尺寸相同试件,在试件进行模拟注浆,借助激光扫描仪对试件在不同配比注浆材料和保养天数后,注浆材料对注浆岩体的节理面影响。结果表明:随水灰比的增大,红砂岩试件的最大剪切应力呈不断减小的趋势,且养护天数越长剪切应力越大,水泥—岩体的黏聚力先增大后减小,而内摩擦角先减小后增大;对试件施加的法向应力越大剪切应力越大,相同法向应力下添加减水剂的水泥—岩体大于未添加减水剂的最大剪切应力;节理面注浆宽度越大,红砂岩试件的最大剪切应力越大,且随水泥水灰比的增大试件的最大剪切应力逐渐减小;随结构面粗糙度的增大,剪切应力呈不断上升的趋势。

In order to determine the influence of the fracture grouting on the physical and chemical properties of the surrounding rock,five red sandstone specimens of the same size were produced through on-site sampling.Simulated grouting was performed on the specimens,and the specimens were grouted in different proportions with the aid of a laser scanner.After the materials and maintenance days,the grouting material affected the joint surface of the grouted rock mass.The results showed that with the increase of the water-cement ratio,the maximum shear stress of the red sandstone specimens was continuously decreasing,and the longer the curing time,the greater the shear stress,and the cement-rock cohesive force first increased and then decreased,and the internal friction angle first decreased and then increased;the greater the normal stress applied to the specimen,the greater the shear stress,and the cement-rock mass with water-reducing agent added under the same normal stress was larger than that without water-reducing agent,The maximum shear stress of the specimen;the greater the grouting width of the joint surface,the greater the maximum shear stress of the red sandstone specimen,and the maximum shear stress of the specimen gradually decreased with the increase of the cement-water-cement ratio;with the roughness of the structural surface with the increase of the degree,the shear stress had a rising trend.