声波及井间层析与地震波衰减探究地面沉降机理——以成都地铁火车南站为例
Acoustic Cross-well Tomography and the Seismic Wave Attenuation to Explore the Mechanism of Land Subsidence,Taking Chengdu Metro South Railway Station as an Example
唐杰生 1黄韬 2龚春荣 3黄强1
作者信息
- 1. 中国建筑材料工业地质勘查中心四川总队,成都 610052;四川省地质工程勘察院集团有限公司,成都 610032
- 2. 四川省地质工程勘察院集团有限公司,成都 610032
- 3. 中国建筑材料工业地质勘查中心四川总队,成都 610052
- 折叠
摘要
利用场地内4个勘探孔,采用井间地震层析成像方法,并结合井间地震波衰减分析,查明了成都轨道交通18号线火车南站沉降原因.成都地铁火车南站基坑东侧泥岩声波速度比西侧低,且穿透泥岩的地震波低频能量强,高频弱,高频成份衰减大;而西侧穿透泥岩的地震波高频能量强,高频成份衰减小.说明基坑东侧,泥岩裂隙较发育,泥岩强度较低,西侧泥岩层则较完整.由于东侧有许多废弃地源热泵深井,泥岩在长期的热交换作用下使岩体产生物理风化.同时,地下水沿泥岩节理裂隙运动,进一步软化泥岩,降低岩体承载能力,导致地面沉陷.在传统的地震波层析成像中引入地震波衰减的分析更加有利于查明岩体性质,从而查明地面沉降病因,采取针对性的工程治理措施.
Abstract
By using 4 exploration holes in the site,cross-well seismic tomography method and cross-well seismic wave attenuation analysis are used to find out the subsidence reason of Chengdu Metro Line 18 South Railway station.The acoustic velocity of mudstone on the east side of foundation pit of Chengdu Metro South Railway Station is lower than that on the west side,and the seismic wave penetrating mudstone has strong low frequency energy,weak high frequency,and large attenuation of high frequency components.On the west side,the seismic wave penetrating mudstone has strong high-frequency energy and small attenuation of high-frequency components.It shows that the mudstone fracture is more developed and the mudstone strength is lower on the east side of the foundation pit,while the mudstone layer is more complete on the west side.There are many abandoned ground source heat pump deep Wells on the east side,mudstone physical weathering occurs under the action of long-term heat exchange.At the same time,groundwater moves along the mudstone joints and fissures,further softening the mudstone,reducing the bearing capacity of the rock mass and leading to ground subsidence.The introduction of seismic wave attenuation analysis into traditional seismic wave tomography is more conducive to identifying the properties of rock mass,thus identifying the cause of ground subsidence and taking targeted engineering treatment measures
关键词
异常沉降/井间地震层析成像/井间地震波衰减/泥岩裂隙Key words
abnormal settlement/cross-well seismic tomography/cross-well seismic wave attenuation/mudstone fissure引用本文复制引用
出版年
2024
NETL
NSTL
万方数据