Study on Longitudinal Deformation Profile of Rock Mass in a Subsea Tunnel     

Shu-Guang Song  Shu-Cai Li  Li-Ping Li  Qian-Qing Zhang  Kai Wang  Yi Zhou 《Marine Georesources & Geotechnology》2016,34(4):376-383

During tunnel excavation, the deformation of surrounding rock due to the unloading of rock mass will vary with time. However, the measured displacement of surrounding rock is only a part of the actual longitudinal deformation profile. There is a need to analyze the longitudinal deformation profile to identify the deformation state and evaluate the stability of surrounding rock mass. In the present article, the variation of pre-deformation of surrounding rock due to excavation was analyzed, and the release coefficient was obtained from the measured results. For the Qingdao subsea tunnel, the measured crown settlement of surrounding rock was analyzed using the regression analysis method, and the longitudinal deformation profile of rock mass was simulated using the numerical calculation method. Moreover, based on the conditions of the subsea tunnel, a solid-fluid coupling model test was carried out to check the reliability of the numerical calculation results. The results of the model test were consistent with the numerical calculation results.  相似文献   

广西近海灾害地质因素及声学反射特征          下载免费PDF全文

李海东  许江  郑江龙  胡毅  张汉女  钟贵才 《应用海洋学学报》2016,35(2):275-283

利用高分辨率地球物理资料及相关历史资料,对北部湾北部的广西近海灾害地质因素进行了地质地球物理解译,识别出海底沙波、海底沙脊、塌陷洼地、冲刷沟槽、浅层气、残积砂体、地层间断、埋藏丘、埋藏古河道等多种灾害地质因素.根据它们出现的频率、规模及声学特征可知:浅层气和埋藏古河道是广西近海最为发育的灾害地质因素,其对海洋工程的施工与建设有较大的危害性.  相似文献   

软岩隧道中双层初期支护的应力情况分析     

姚正源 《探矿工程》2018,45(7):73-76

两水隧道穿越的地层主要岩性为炭质千枚岩,地质情况较差,围岩破碎度高,节理发育。自2009年两水隧道开工建设以来,隧道工程问题层出不穷,出现了初期支护开裂、破坏,甚至出现二衬开裂、掉块,仰拱隆起等严重的隧道结构破坏现象,施工进度缓慢。在进口桩号为DK359+712～ DK359+742段采用双层初期支护和单层二次衬砌的支护方式,取得了良好的效果。通过应力情况分析为炭质千枚岩隧道的支护选型提供了依据。  相似文献   

铺前—清澜断裂西支晚更新世活动特征     

刘风香  苗雨雁  荆振杰  杜海娥 《世界地质》2018,37(1):148-153

海域浅层地震探测调查表明,铺前—清澜断裂向北西海域方向延伸,断裂走向NW-SE,倾向SW,为高倾角的正断层;在地震剖面上,断裂断错了第四系地层;进一步应用钻探技术对铺前—清澜断裂进行探测研究,结合层序地层学、岩性岩相分析与年代测定等方法建立了钻孔联合剖面,揭示断层性质为正断层,倾向SW,断距4.0 m,断层的最新活动时代为晚更新世,第四纪表现为张性活动,断裂的平均垂直速率为0.15 mm/a。  相似文献   

黄骅坳陷古生界潜山储层沥青成因判识     

王鑫  周立宏  金凤鸣  付立新  楼达 《地质论评》2021,67(Z1):67z1123-67z1124

正黄骅坳陷古生界潜山是大港油田重要的油气勘探领域,近年来,先后在王官屯、乌马营潜山古生界发现油气流,且均为石炭—二叠系煤系源岩供烃成藏,如王官屯潜山王古1井二叠系石盒子组发现天然气,同位素特征判断为煤成天然气。这些发现拓展了古生界潜山的勘探领域,表明了石炭—二叠系煤系烃源岩的油气充注范围不仅仅局限于奥陶系碳酸盐岩储层,石炭—二叠系的碎屑岩储层也可以充注成藏,证实了古生界潜山具有更大的油气勘探价值。随着勘探进程与理论认识的不断深化,  相似文献   

渤海湾盆地大型基岩潜山储层特征及其控制因素——以渤中19- 6凝析气田为例     

叶涛  牛成民  王清斌  代黎明  李飞 《地质学报》2021,95(6):1889-1902

渤中19-6气田是渤海湾盆地近期发现的规模最大的深层变质基岩凝析气田,探明储量超过千亿立方米,气柱高度超1000 m,现今埋深大于4000 m,储层规模大但非均质性强.基于三维地震、钻井、测井以及薄片资料,明确了基岩潜山储层的发育特征,并探讨了优质储层形成的主控因素.结果表明:基岩潜山以太古宇变质花岗岩为主要的储集岩性,储集空间主要为构造裂缝,同时发育沿裂缝溶蚀形成的孔隙及构造破碎粒间孔,平均孔隙度为5％,平均渗透率为6.48×10-3μm2.脆性岩石、构造挤压以及风化作用共同控制了规模性储层的形成:① 研究区90％的岩石为低抗压强度的变质花岗岩,为裂缝的形成提供了物质基础;② 印支期强烈的挤压为规模性裂缝的形成提供了外部动力,是大规模储层发育最为关键的因素;不同构造位置裂缝发育程度不同,造成了储层平面分布的非均质性;③ 长期的风化作用使得潜山上部300 m以内的储集物性得到进一步改善,控制了潜山垂向上储层的非均质性.  相似文献   

水平定向勘察技术在长大隧道勘察中的应用现状与展望          下载免费PDF全文

吴纪修  尹浩  张恒春  孙华峰  袁维  曹龙龙  李鑫淼  施山山  王文  薛倩冰  梁楠 《探矿工程》2021,48(5):1-8

西南高山峡谷区是我国重大铁路交通工程规划建设的重点区域,如川藏铁路建设等,深埋、长大隧道数量多,常规垂直孔勘察方法无法满足精细化地质勘察的需求。采用水平定向勘察技术沿隧道设计轴线施工水平定向孔为隧道勘察提供了一种有效的手段。水平定向勘察技术的核心包括钻进技术、取心技术、钻孔轨迹控制技术、随钻测量/随钻测井技术、综合测井技术等。结合国内外水平定向勘察技术的发展应用现状,分析了目前存在的问题,提出了开展单次钻探长度超3000 m的水平定向多工艺钻进关键技术与装备攻关,构建安全、高效、经济合理的水平定向勘察技术体系的建议。  相似文献   

复杂地质条件和敏感环境中基坑设计实践及关键技术          下载免费PDF全文

邵晨晨 《探矿工程》2021,48(6):102-108

上海某国际金融大厦深大基坑项目北侧紧邻运营轨道交通8号线区间隧道,最近处仅7.87 m,南侧与现有世博共同管沟净距2.0~3.0 m,基坑变形控制要求高,周边环境敏感。同时,本项目位于黄浦江畔,场地浅层为典型的淤泥质软土地层,下部为富含承压水粉（砂）土层,且微承压水层与第一、第二承压水层互为连通,止水帷幕无法隔断承压水层,地质条件复杂。设计采用分坑施工、被动区加固、预应力伺服钢支撑系统、抽灌一体化降水方案、超深地下连续墙、跟踪注浆、型钢垫层等技术方案。实测结果表明,区间隧道的最大变形6.52 mm,共同管沟的最大变形15.3 mm,其最大变形均满足变形控制要求,确保了运营区间隧道和共同管沟的安全。  相似文献   

Reservoir Characteristics and Genetic Mechanisms of the Mesozoic Granite Buried Hills in the Deep‐water of the Qiongdongnan Basin,Northern South China Sea     

YOU Li  XU Shouli  MAO Xuelian  ZHONG Ji  JIAO Yaoqi  XIONG Xiaofeng 《《地质学报》英文版》2021,95(1):259-267

Due to its structure,rock and mineral composition,fluid and other factors,the granite Buried Hill Reservoir is highly heterogeneous with a complex longitudinal structure and a reservoir space made up of a combination of dissolution pores and fractures.This paper is based on current understanding of tectonic evolution in the northern part of the South China Sea,in conjunction with the seismic phase characteristics.It is determined that the meshed fault system was formed by three stages of movement-tectonic compression orogeny during the Indochinese epoch,strike-slip compression-tension during the Yanshanian Period,early fracture extension activation during the Himalayan-which controlled the distribution of the Buried Hill Reservoir.Drilling revealed two types of buried hills,faulted anticline and fault horst,their longitudinal structure and the reservoir space type being significantly different.The mineral composition,reservoir space and diagenetic characteristics of the reservoir rocks and minerals were analyzed by lithogeochemistry,micro section and logging etc.,it thus being determined that the Mesozoic rocks of the Songnan Low Uplift in the Qiongdongnan Basin are mainly composed of syenogranite,granodiorite,monzogranite,which is the material basis for the development of the Buried Hill Reservoir.The content of felsic and other brittle minerals is more than 70%,making it easy for it to be transformed into fractures.At the same time,the weathering resistance of granodiorite and monzogranite is weaker than that of syenogranite,which is easily weathered and destroyed,forming a thick sand gravel weathering zone.With increasing depth of burial,weathering and dissolution gradually weaken,the deep acidic fluid improving the reservoir property of internal fractures and expanding the vertical distribution range of the reservoirs.The research results lay a foundation for the exploration of Buried Hill in the deep-water area of the Qiongdongnan Basin.  相似文献   

渤海湾盆地石臼坨东428潜山构造成因解析:华北克拉通破坏的深度揭示     

王宇  徐春强  郭玲莉  刘永江  王光增  刘博  李三忠  关庆彬  蒋立伟  陈昭旭  李法坤  周琦杰  袁菁莲 《大地构造与成矿学》2021,45(1):219-228

渤海湾盆地是在中生代华北克拉通破坏基础上,经由新生代深埋形成的叠合盆地,遭受了多期不同性质构造叠加改造。渤海海域油气资源的勘探逐步走向深层,深部潜山油气藏成为重要的勘探目标。本文以石臼坨东428潜山构造(以下简称428构造)为例,探索渤海湾盆地潜山的形成和构造演化。基于前人对渤海湾盆地内构造和储层特征的研究成果,通过对地震剖面的精确解析,结合相干切片和其他地质资料,系统研究428构造各个阶段的变形特征,特别是对428构造的断裂特征进行了平面和剖面上的解析与断裂组合分析。结果发现:428构造东、西侧现今差异主要是由一条斜跨该构造的NEE向断裂导致的,对比邻区野外应变测量分析,识别出五期构造应力场,分别对应于印支期、燕山期和喜山期的各阶段应力场变化,并结合428构造及其周缘残留地层等方面的证据,进而认为428构造经历了中生代印支期-燕山早期逆冲、燕山中-晚期伸展、燕山末期挤压及新生代右行右阶的走滑-拉分构造叠加的多期复合构造模式。  相似文献