锚注联合支护效果的数值模拟研究

Research on Supporting Effect of Bolt-grouting Combined Support by Means of Numerical Simulation

研究目的:采用数值计算的方法从控制隧道变形、塑性区扩展,提高锚杆锚固力,减少初期支护受力等方面对锚注支护与常规喷锚支护的支护效果进行对比研究。研究结论:以具体工程为例,采用数值计算的方法对破碎软弱围岩条件下锚注支护与常规喷锚支护的支护效果进行了系统分析和对比研究。研究表明:对松散、破碎围岩而言,锚注联合支护通过提高围岩强度、锚杆锚固力,从而提高围岩自承能力及支护结构作用在洞室周边的径向压力,与常规喷锚支护相比可有效限制围岩变形,抑制塑性区的发展,提高锚杆锚固力,减少钢拱架及喷射混凝土层的受力,提高初期支护稳定性,特别适宜于破碎软弱围岩的支护。

Research purposes：By means of numerical simulation,the comparative research is done on supporting effects of bolt-grouting support and bolt-shotcrete support in terms of controlling tunnel deformation and expansion of plastic zone,increasing anchoring force and decreasing the stress on initial support.Research conclusions：Based on the concrete engineering project,in this paper,a systematic analysis is made of and a comparative research is done on the supporting effects of bolt-grouting support and bolt-shotcrete support under condition of fractured soft surrounding rocks by means of numerical method.The research shows that for fracture soft surrounding rock,the bolting-grouting combined support increases the self supporting capacity of surrounding rock and the radial supporting pressure on the tunnel circumference by increasing the strength of surrounding rock and anchoring force of bolt,and it is more efficient than bolt-shotcrete support in terms of confining the deformation of surrounding rock,controlling the expansion of plastic zone,increasing anchoring force,decreasing the stress on steel arch and shotcrete,improving initial support stability.Therefore,the bolt-grouting support is especially used for supporting the fractured soft surrounding rock.