大型地下厂房岩锚梁爆破安全控制标准研究  

RESEARCH ON SAFETY STANDARD FOR ROCK ANCHOR BEAM UNDER BLASTING VIBRATION IN LARGE UNDERGROUND POWERHOUSE

作　　者：陈明[1] 卢文波[1] 易长平[1] 唐浩[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《岩石力学与工程学报》2006年第3期499-504,共6页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金重点项目(50239070);教育部科学技术研究重点项目(02133);湖北省自然科学基金项目(2002AB006)

摘　　要：利用动力有限元数值模拟,研究爆破震动荷载作用下岩锚梁的动态响应特性,研究结果表明爆破震动作用下保证岩锚梁的安全关键在于防止岩锚梁与岩台黏结面被拉裂,应严格控制岩锚梁水平向质点峰值振动速度。结合龙滩水电站地下厂房开挖爆破震动对岩锚梁影响控制的工程实例分析,综合考虑岩锚梁的结构特点、混凝土的强度性能、强度随龄期的增长规律、岩锚梁与岩台黏结面的微观结构及强度等因素,探讨大型地下厂房岩锚梁龄期小于28d条件下进行下层岩体开挖的可行性及不同龄期的爆破安全质点振动速度控制标准。认为岩锚梁浇注后28d内,爆破安全振动速度可以按新浇混凝土的控制标准确定;龄期大于28d的岩锚梁,振动速度不超过7cm/s的控制标准有一定安全储备。On the basis of the numerical simulation of dynamic finite element method（DFEM）, the dynamic response of rock-anchored beam of large underground powerhouse under blasting vibration is studied. It is found that the key to ensure the safety of the rock-anchored beam under blasting vibration is to prevent the cracking of the bonding interface between the beam and the vertical rock wall, and to control the horizontal peak particle velocity, which is vertical to the side wall. Combined with the blasting vibration control practice of the rock-anchored beam at Longtan Hydropower Station, considering the comprehensive factors such as the structure characteristic of rock-anchored beam, the strength properties of concrete, the strength development with the increase of the cured age of young concrete, the microstructure and the strength of the bonding interface, the feasibility of rock excavation by blasting in underground powerhouse below the beam is studied under the condition that the cured age of concrete is no older than 28 d; the control standard of peak particle velocity（PPV） for rock-anchored beam in different cured ages is proposed. It is concluded that the PPV control standard for young concrete proposed by code could be used to rock-anchored beam with an age no older than 28 d; and the PPV of 7 cm/s for rock-anchored beam with an age older than 28 d has certain safety mar^in.

关 键 词：岩石力学 地下厂房 岩锚梁 爆破震动 质点峰值振动速度 控制标准 

分 类 号：TU45[建筑科学—岩土工程]