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为了研究碳纤维水泥基复合材料对节理岩体的加固效果、加固机理及最优碳纤维掺量值,在超细水泥、粉煤灰、矿粉、硅灰等修复材料中,考虑0、0.25％、0.50％、0.75％、1.00％这5种不同的碳纤维掺量,对加固前、后节理岩样分别进行了直剪试验.研究结果表明:加固前、后节理岩样的剪切力-剪切位移曲线变化特征明显,由无峰值强度曲线转变为有峰值强度曲线,并出现明显的应变软化阶段和残余强度阶段;碳纤维掺量(质量分数)从0增加到1.00％时,节理岩样的峰值抗剪强度、残余抗剪强度在5种法向应力下分别提高13.0％～54.1％和0.61％～44.7％,剪切刚度增大32.4％～216.8％,黏聚力和摩擦角分别增大127.3％～266.5％和4.3％～20.4％;当碳纤维掺量为0.75％左右时,节理岩样加固后抗剪性能的综合增强效果最为明显;结合节理面形貌特征和加固后剪切破坏面特征分析发现,水泥浆复合材料对节理面具有较好的充填作用和胶结作用;在水泥基材中掺入碳纤维时,一方面类似于“加筋”材料,可在纯水泥浆的基础上进一步提高浆体的强度和整体性,限制节理面剪切过程中微裂纹的开展,另一方面碳纤维对受剪浆体提供了较好的“锚固”作用,进一步增加浆体与节理面的粘结性能,使得浆体本身、浆体与节理面之间胶结面的抗剪性能明显增强,从而显著提升加固后节理岩体的综合抗剪性能.“,”In order to investigate the reinforcement effect,mechanism and the optimum carbon fiber content of carbon fiber cement-based composite material,taking 0,0.25％,0.50％,0.75％,1.00％ as five different kinds of carbon fiber content into consideration,the direct shear test was conducted on the rock specimens before and after reinforcement by dint of the ultrafine cement,fly ash,mineral powder,silica fume and other repair materials.The results show that:the shear stress-shear displacement curves of the jointed rock specimens before and after reinforcement are obviously changed,which are transformed from the absence of peak intensity to peak intensity curves.And there are significant strain softening stages and residual strength stages.With the carbon fiber content increases from 0 to 1.00％,the peak shear strength and residual shear strength of jointed rock specimens under five kinds of normal stress cases increase by 13.0％-54.1％ and 0.61％-44.7 ％ respectively.The shear stiffness increases from 32.4％ to 216.8％.The cohesion and friction angle of the shear strength parameters increase by 3.4％-20.4％ and 127.3％-266.5％,respectively.In comparison,when the carbon fiber content is 0.75％,the comprehensive enhancement effect of the shear resistance after reinforcement is obvious.According to the morphological features of joints and shear failure characteristics after reinforcement,it is found that the cement composite has a good filling and cementation effect on the jointed surfaces.When the carbon fibers are incorporated into the cement matrix,on the one hand,it is similar to “stiffened” material,and the strength and integrity of the slurry can be further enhanced on the basis of pure water slurry to limit the development of micro-cracks during the shear process of the jointed surface.On the other hand,carbon fiber provides a good “anchorage” effect on the sheared slurry,which can further increases the bonding performance of the slurry and the jointed surfaces to significantly increase the shear resistance of the slurry itself and the cementing surface of slurry and jointed surface.Hence,after consolidation,the comprehensive shear resistance of the jointed rock mass can be improved significantly.