摘要
当地下厂房岩梁壁座缺失或超挖较大时,岩壁吊车梁与修补混凝土需要同期浇筑和施工,岩壁吊车梁与常规岩梁体型相比有了较大变化、受力十分复杂。为此,采用能较好地模拟不连续面的非连续力学方法,对岩梁与岩壁结合面采用接触面单元进行模拟,分析了标准设计断面和壁座修补断面两种情况下的岩壁吊车梁锚杆受力、岩梁与岩壁结合面的应力与变形,以及修补断面岩梁的潜在破坏形式,并对促进岩梁稳定的措施进行了探讨。结果表明:采用非连续力学方法计算出的岩梁锚杆受力、岩梁和岩壁结合面上的应力和变形分布特征与实际情况较为接近;对于岩梁壁座缺失的情况,采用混凝土修补以及附壁墙加强措施是合适的,轮压荷载引起的锚杆应力、岩梁与岩壁结合面法向变形和切向变形在可接受范围内;在超载情况下,修补断面岩梁的破坏是以锚杆先出现受拉破坏,进而岩梁与岩壁结合面剪切破坏的破坏型式;在岩梁的稳定性分析中,不仅要考虑厂房开挖变形引起的锚杆释放应力,也要考虑其引起的岩梁和岩壁结合面应力变化的影响。
For the condition of that the concrete placements and constructions for both the rock-bolted crane beam and concrete mending are to be synchronously carried out for the case without walling crib for the rock-bolted crane beam or the case of over-excavation,the contact-plane element of the joint-plane between rock-bolted crane beam and rock wall is simulated with the discontinuous mechanical method that can better simulate discontinuous plane,from which the stress of the anchor-bolt for the rock-bolted crane beam and the stress and deformation of the joint-plane between rock-bolted crane beam and rock wall as well as the potential failure mode of the rock-bolted crane beam in the mended section under both the conditions of the standard design section and the mended section of the walling crib are analysed herein,while the measures for improve the stability of the rock-bolted crane beam are discussed as well.The result shows that the stress of the anchor-bolt for the rock-bolted crane beam and the distribution characteristics of the stress and deformation of the joint-plane between rock-bolted crane beam and rock wall are more approachable to those of the actual conditions.For the case without walling crib for the rock-bolted crane beam,adopting the reinforcing measures of mending with concrete and attached wall is suitable,for which the stress of anchor-bolt,the normal deformation and tangential deformation of the joint-plane between rock-bolted crane beam and rock wall caused by wheeling load are within the acceptable range.Under the overload condition,the failure mode of the rock-bolted crane beam occurred at the section to be mended is that tensile failure of anchor-bolt occurs at first and then shear failure of the joint-plane between rock-bolted crane beam and rock wall occurs in turn.In the analysis of the stability of rock-bolted crane beam,it is not only necessary to consider the stress release from the anchor-bolt caused by the deformation from the excavation of powerhouse,but influence from the stress va
作者
李良权
万祥兵
陈建林
应和平
LI Liangquan;WAN Xiangbing;CHEN Jianlin;YING Heping(PowerChina Huadong Engineering Corporation Limited,Hangzhou 311122,Zhejiang,China)
出处
《水利水电技术》
北大核心
2019年第5期124-135,共12页
Water Resources and Hydropower Engineering
基金
国家自然科学基金资助项目(51309243,51779251)
关键词
岩石力学
地下厂房
岩壁吊车梁
稳定性分析
安全系数
rock mechanics
underground powerhouse
rock-bolted crane beam
stability analysis
safety factor
