聚合物水泥浆液-煤体界面过渡区力学性能研究

Study on mechanical properties of polymer cement slurry-coal interface transition zone

提出了超前深孔注浆加固技术;利用VAE乳液对水泥基材料进行改性,通过轴拉试验及立方体抗压试验,研究了不同掺量VAE乳液对水泥基材料与煤体界面黏结强度及水泥基材料固结煤体的抗压强度的影响;结合微观电镜扫描,分析了VAE改性水泥基材料结石体与煤体界面过渡区的微观结构特征。研究结果表明:复合浆液水灰比随聚灰比的增大呈现出先降低后增长的趋势,VAE乳液提高了浆液与煤体界面黏结强度及浆液固结煤体试块的抗压强度;掺入VAE乳液,使水泥浆液的孔隙率降低,提高了强效应层结构的密实性;VAE乳液会扩散至普通水泥浆内部形成聚合物薄膜"纽带"结构,改善水泥基材料与煤体界面的组成结构,从而提高了水泥基材料与煤体黏结强度。

Advanced deep hole grouting reinforcement technology is proposed. The effects of VAE emulsion on cement-based materials were studied. The effects of VAE emulsion on the bonding strength between cement based materials and coal and the compressive strength of cement based materials were studied by axial tensile test and cube compression test. The microstructure characteristics of VAE modified cementitious materials and coal interface transition zone were analyzed by scanning electron microscopy. The results showed that the water cement ratio of composite grout showed a trend of first decrease and then increase with the increase of aggregate cement ratio. VAE emulsion increased the interfacial bond strength between slurry and coal and the compressive strength of slurry consolidated coal block. The porosity of cement slurry decreased with the addition of VAE emulsion,and the compactness of the effective layer structure was enhanced. The VAE emulsion diffused into the ordinary cement paste to form a polymer film "tie"structure, which improved the composition structure of the cement based material and coal interface,thus enhancing the bond strength between the cement based material and the coal body.