拉力型岩石锚杆临界锚固长度的试验研究

Experimental Study of Critical Anchorage Length of Tensile-type Rock Anchor

按照临界锚固长度理论,通过在低、中和高3种强度混凝土中不同长度锚杆的拉拔试验,研究了岩石中拉力型锚杆临界锚固长度的试验条件和方法,并且与其他研究成果相结合,进一步分析了临界锚固长度的试验和判别方法。此次试验结果表明:峰值应力转移、零值剪应力转移大体是同时发生的,此时峰值和零值点间的空间距离就是临界锚固长度。拉力型岩石锚杆临界锚固长度是普遍存在的,而且在试验条件都一致时,可以按照本文的试验方法测得相同的临界锚固长度安全值,并且采用此值为依据进行工程设计是科学合理的。

According critical anchorage length theory, and different pull out test with different length rock bolts in three differentstrength concretes, which include low, middle and high, experimental condition and distinguish method of tensile type rock anchorcritical anchorage length in rock were studied, with other studying results, experiment condition and distinguish of critical anchoragelength were studied future. The results showed that peak value stress transfer and zero value shear stress transfer appeared almost at thesame time, the space distance between peak value and zero value is critical anchorage length. Critical anchorage length of tensile typerock anchor is ubiquitous, and in the same experiment situations, the same safety value of critical anchorage length could be obtained,and engineering design is reasonable based on it.