深埋圆形隧道衬砌-锚杆支护结构弹塑性解答

ELASTOPLASTIC SOLUTION OF SURROUNDING ROCK STRUCTURE OF LINING AND BOLT SUPPORT FOR DEEP BURIED CIRCULAR TUNNEL

文章采用等效材料法,基于Drucker-Prager屈服准则推导了具有衬砌-锚杆支护深埋隧道在不同施工阶段下的弹塑性解答,并进行FLAC3D数值模拟验证。结果表明:塑性区位于衬砌内部,锚杆的锚固作用对其塑性区扩展响应不明显,塑性区扩展到锚固区,软岩中锚杆锚固作用对抑制塑性扩展的响应较好;塑性区扩展到锚固区时,塑性区半径与锚杆的弹性模量呈负相关趋势,塑性区半径与锚杆的支护角度呈正相关趋势,软岩中锚杆锚固作用对抑制塑性区扩展的效果更为明显。

Based on the Drucker-Prager yield criterion,the elastic-plastic solution of deep buried tunnel with lining-anchor support under different construction stages is derived by using the equivalent material method,and the FLAC3D numerical simulation is verified.The results show that the plastic zone is located inside the lining,and the anchoring effect of the bolt has no obvious response to the expansion of the plastic zone.The plastic zone extends to the anchorage zone,and the anchoring effect of the bolt in soft rock has a good response to the inhibition of plastic expansion.When the plastic zone extends to the anchorage zone,the radius of the plastic zone is negatively correlated with the elastic modulus of the bolt,and the radius of the plastic zone is positively correlated with the supporting angle of the bolt.The anchoring effect of the bolt in soft rock is more obvious to inhibit the expansion of the plastic zone.