隧道开挖及爆破对地表高压铁塔影响的flacd分析.docVIP

隧道开挖及爆破对地表高压铁塔影响的FLACD分析 ———————————————————————————————— 作者： ———————————————————————————————— 日期： 隧道开挖及爆破对地表高压铁塔影响的FLAC3D分析 肖欣欣 李夕兵 宫凤强 〔中南大学 资源与平安工程学院，湖南 长沙 410083〕 摘要：以长湘高速公路李家冲隧道工程为背景，针对地表高压铁塔塔基受到隧道开挖及爆破影响的情况，运用FLAC3D对铁塔4个塔基的沉降及质点振动速度进展了数值分析。并与现场实测数据进展比照分析，结果说明：〔1〕隧道开挖后铁塔塔基发生沉降，最大沉降量发生在测点3即1号塔基处，为3.55mm。〔2〕施加爆破动载荷后，最大沉降量增量出现在1号塔基为2.23mm ，其他塔基沉降量也有不同程度的增大，在允许的平安振速范围之内。质点振动速度与隧道开挖中线距离有关，距隧道开挖中线距离越近质点振速越大，反之那么越小。分析结果与实际观测结果相吻合，并给出了防止爆破震动诱发地表铁塔塔基失稳塌陷的几条建议。 关键词：塔基沉降；质点振速；FLAC3D；数值分析 中图分类号：TU454 文献标识码：A 文献编号： Analysis of Tunnel Excavation and Explosion Influence on High-pressure Tower with FLAC3D Xiao Xinxin , Li Xibing Gong Fengqiang (School of Resource and Safety Engineering, Central South University, Changsha, Hunan 410083, China) Abstract: Set in Li Jiachong tunnel project in ChangXiang express way, in a reference to the influence of tunnel excavation and explosion on high-pressure tower foundations, this paper uses FLAC3D software to numerically simulate settlement and particle velocity of four foundations in the iron tower and the conclusion in comparison with field data states as follows:〔1〕Foundation settlement in iron tower after tunnel excavation do exists and the maximum settlement value is greatest in Foundation 1, that is 3.55mm. 〔2〕When exposed on dynamic explosive load, the maximum displacement increment exists in Foundation 1, whose value is 2.23mm, and appearances of other different foundation increment are also found.〔3〕The amplitude of particle velocity of foundations is , which is within the safety velocity range. Particle velocity has something to do with straight-line distance under excavation and the nearer the distance from the particle to the excavation middle-line is, the greater the particle velocity value is and vice versa. The analytical results coincide with field results and suggestions on how to avoid instability and subsidence of iron tower foundations after explosion are made. Key words: subsidence of tower foundat