摘要
在城市地铁勘察中,岩溶、断裂及软土等不良地质是主要工程隐患,严重威胁着工程后续的施工建设安全,在常规地质勘察之外,有必要采用有效且适宜于城市环境的物探手段予以查明,提高勘察资料的可靠度和覆盖面。城市环境复杂,场地条件限制多,不同物性干扰强,整体物探环境恶劣。笔者以徐州地铁4、5号线勘察为例,首先针对具体场地条件进行物探环境评估;其次对各种物探方法进行技术适应性分析,提出场地环境与技术方法的最佳耦合;最后,总结出一套适用性与操作性强的物探技术模式。综合对比分析结果表明:①微动、瞬变电磁等技术可作为城区主要的地面物探手段,能初步查明岩溶、断裂等地质体的位置与赋存特征;②在岩溶精细探测上,孔间CT(电磁波)技术能进一步圈定岩溶的发育规模和空间位置;③地面与孔间物探的合理选用或联合应用,能够提供不同勘察阶段、不同勘察精度所需的地质资料,满足城市地铁勘察需求。
In subway investigation,undesirable geological conditions such as karst,fracture,and soft soil are the main hidden dangers of the project,which seriously threaten the safety of the subsequent construction of the project.In addition to the conventional geological survey,it is necessary to adopt effective and suitable geophysical methods for the urban environment to improve the reliability and coverage of survey data.The urban environment is complex,the site conditions are limited,the interference of different physical properties is substantial,and the overall geophysical environment is harsh.Taking the survey of Xuzhou Metro Lines 4 and 5 as an example,this paper firstly evaluates the geophysical environment according to the specific site conditions;secondly,analyzes the technical adaptability of various geophysical methods,and proposes the best coupling of the site environment and technical methods;finally,summarizes the set of geophysical technology models with strong applicability and operability.The results of the comprehensive comparative analysis show that①microtremor,transient electromagnetic,and other technologies can be used as the main ground geophysical means of urban areas and can preliminarily identify the location and occurrence characteristics of karst,fracture,and other geological bodies;②in the fine detection of karst,Interhole CT(electromagnetic wave)technology can further delineate the development scale and spatial location of karst;③Reasonable selection or combined application of ground and inter-pore geophysical exploration can provide geological data required for different survey stages and different survey accuracy,and meet the needs of urban subways.
作者
李乾坤
胡清茂
赵晓亮
郑江波
LI Qiankun;HU Qingmao;ZHAO Xiaoliang;ZHENG Jiangbo(Xuzhou Urban Rail Transit CO.,LTD.Xuzhou 221000,China;China Railway Liuyuan Group CO.,LTD.Engineering Survey Institute,Tianjin 300308,China)
出处
《物探化探计算技术》
CAS
2024年第2期206-214,共9页
Computing Techniques For Geophysical and Geochemical Exploration
关键词
不良地质体
徐州地铁4、5号线
地铁勘察
微动
瞬变电磁
地震映像
孔间CT
undesirable geological body
Xuzhou metro line 4 and 5
subway exploration
mircrotremor
transient electromagnetic
seismic image
interhole CT
