共查询到20条相似文献，搜索用时 968 毫秒
1.
曹海波 《国土资源导刊(湖南)》2013,(8)
阐述了长沙引水工程23标崔家冲特殊地质处理工程在施工过程中对超大断层破碎带采取的处理措施,主要指出破碎带的注浆机制.从破碎带岩体注浆方案设计、注浆设备、长管棚及超前支护施工工艺、施工方法、施工技术措施和施工质量控制等方面,系统研究了长沙引水及地质环境崔家冲特殊地质工程隧洞的破碎带超前注浆技术、长管棚施工技术及超前支护技术等. 相似文献
2.
工程隧洞施工不仅可能存在因突涌水导致的安全隐患问题,而且还会在一定程度上破坏工程区地下水渗流场平衡,影响地下水的正常循环,存在影响或疏干地下水而导致的环境影响问题,处置不当还可能造成严重的环境影响及社会稳定问题。本文以滇中引水工程某深埋长隧洞为依托,采用GMS数值模型对不同施工工况下隧洞涌水量、地下水水位变化、主要泉点影响程度、运行期水位恢复情况等进行预测研究,为合理评价隧洞工程建设可能导致的地下水环境影响程度、研究制定渗控标准等提供合理、准确、可行的依据。 相似文献
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4.
超长隧洞施工测量属于超规范作业,为保证超长隧洞贯通,必须对超长隧洞施工测量进行研究。对隧洞施工测量中洞口控制网布设、数据处理及其误差对贯通的影响与洞内基本控制网的布设、平差及检核方法等若干问题进行了研究,所得成果已运用于引黄入晋工程中的南干5#和7#超长隧洞施工测量中,确保了两超长隧洞的顺利贯通。 相似文献
5.
超长隧洞施工测量若干问题研究 总被引：2，自引：0，他引：2
超长隧洞施工测量属于超规范作业，为保证超长隧洞贯通，必须对超长隧洞施工测量进行研究。对隧洞施工测量中洞口控制网布设、数据处理及其误差对贯通的影响与洞内基本控制网的布设、平差及检核方法等若干问题进行了研究，所得成果已运用于引黄入晋工程中的南干5^#和7^#超长隧洞施工测量中，确保了两超长隧洞的顺利贯通。 相似文献
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某国家重大引调水工程引水隧洞将穿越聚龙山向斜可溶岩地层，可能面临严重岩溶涌突水问题。为了查明隧洞突涌水条件，选择岩溶水害风险较低的引水方案，综合采用岩溶水文地质调查、水化学与同位素分析等方法对聚龙山向斜岩溶水流系统特征进行了识别。结果表明:聚龙山向斜含水系统具有"两含夹一隔"的多层结构，下部二叠系主要为埋藏型岩溶弱发育区，而上部三叠系裸露型岩溶区中发育了具有多级水流系统的巨型岩溶汇水盆地。穿聚龙山向斜段工程论证的3个方案中，A线方案从向斜西段岩溶水系统的补给区穿越，隧洞穿可溶岩段长度短、且全部为埋藏型岩溶，剖面上绕避了三叠系岩溶汇水盆地，发生岩溶涌突水的风险低；而B线方案和C线方案均进入了三叠系岩溶汇水盆地，穿越裸露型可溶岩段的长度大，遭遇高压岩溶突水的风险高，故推荐A线引水方案。研究成果可为引水隧洞线路比选提供科学依据，对类似深埋长隧洞工程建设也具有参考价值。 相似文献
7.
王卫平 《国土资源导刊(湖南)》2002,21(2):130-132
针对长沙市"红层"中极软岩石的物理力学特性以及岩样单轴抗压强度偏低导致评价岩石地基承载力偏低的问题进行分析,提出了用标准贯入和动力触探手段确定岩石地基承载力的可行性,并结合工程实例作了说明. 相似文献
8.
万家寨引黄入晋工程是一项大型的国家重点调水工程 ,工程总设计造价 180亿元。目前 ,对于从万家寨到太原的一期工程而言 ,大多数工程已经阶段性竣工 ,其余工程也正在施工 ,预计 2 0 0 1年通水到太原。从它的超长距离、大流量、多隧洞、超长隧洞和具有大型地下泵站等特点来看 ,确系全国之最、举世罕见。在该工程的施工测量中 ,有许多施工测量工作是超规范作业 ,存在着大量的特殊问题需要进行研究。作者对这些问题进行了大量深入地研究 ,取得了一些有益的结论。这些结论已经被应用于该工程的施工测量中 ,并且它们的正确性大部分已被工程实践所验证 相似文献
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重庆市2011年扩大红层找水层位,从红层拓展到岩溶地区,实施的岩溶找水示范工程取得突破。据重庆市国土房管局负责人介绍,重庆市红层找水工程已进入常态化,连续9年列为市委、市政府“民心工程”。 相似文献
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根据对南京地区 2 8根软岩嵌岩桩原位测试资料的整理和分析 ,认为目前建筑规范中推荐的有关嵌岩桩端阻力计算公式不适用于软岩嵌岩桩 ,并在对软岩嵌岩长桩端阻力各影响因素分析的基础上 ,采用线性拟和的方法 ,给出软岩嵌岩桩偏于保守的极限端阻力计算公式 相似文献
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软岩洞穴的分布特征与软硬岩层的相间组合、岩层产状、地质构造、地下水排泄条件及地形地貌等因素有关。成因上 ,以水动力机械侵蚀主导作用而区别于岩溶地区的溶洞。 相似文献
12.
地震会对核电站安全造成影响。随着核电站的数量越来越多, 有必要关注在地震下核电站的安全。核反应堆厂房是核电站重要的组成部分, 研究其地震响应对核电站有着重要意义。基于直接法, 考虑了3种不同场地(中硬土、软岩、硬岩)在地震下的塑性变形和土的滞回阻尼, 使用FLAC3D对土-核反应堆厂房模型系统进行了三维建模。为了捕捉上部结构与下部岩石/土壤之间的分离与滑动, 在核反应堆厂房基础与岩石/土壤表面设置接触面单元。上层结构以集总质量模型模拟, 同时考虑土-结构相互作用下基岩深度对核反应堆厂房基础地震响应的影响, 最终得到核反应堆厂房结构杆件的加速度反应谱、剪力、基础的摇动和基础不均匀沉降以及侧向位移。结果表明: 在中硬土场地中, 位移、剪切力随基岩深度的增大而减小; 在硬岩场地中, 位移和剪切力响应的规律呈相反趋势; 在软岩场地中, 上部结构响应的规律较为复杂。对于基础摇动和基础不均匀沉降, 在中硬土场地中, 其呈现的规律随基岩深度增大而减小; 在软岩和硬岩场地中, 并无明显规律。基础不均匀沉降可直接反映结构的破坏情况。中硬土场地下基础不均匀沉降超过容许值, 所以基础不均匀沉降对核反应堆厂房的影响不容忽视, 这对核电站的安全设计十分重要。 相似文献
13.
《山地科学学报》2021,(5)
Large squeezing deformation of layered soft rock tunnel under high geo-stress has a significant time-dependent deformation behavior. In this paper, we studied the deformation mechanism during the construction period of deep-buried softrock tunnel by means of a combination of field observations and a numerical method. First, a new classification criterion for large deformations based on the power exponent variation law between the deformation and the strength-stress ratio is proposed. Then, the initial damage tensor reflecting the bedding plane(joint) distribution and an equivalent damage evolution equation derived from the viscoplastic strain are introduced based on the geometric research method, i.e., a new rheological damage model(RDL model) of layered soft rock is established consisting of elastic, viscous, viscoelastic, viscoplastic and plastic elements. A field test was conducted on the Maoxian tunnel in Sichuan province, southwestern China, which is in broken phyllite(layered soft rock) under high geo-stress. The tunnel has experienced large deformation due to serious squeezing pressure, thus we adopted double primary support method to overcome the supporting structure failure problems. The rheological parameters of phyllite in the Maoxian tunnel were recognized by using SA-PSO optimization, and the RDL model does a good job in describing the time-dependent deformation behavior of a layered soft-rock tunnel under high geo-stress. Thus, the RDL model was used to investigate the supporting effect and bearing mechanism of the double primary support method. Compared with the single primary support method, the surrounding rock pressure, secondary lining force, surrounding rock deformation, and the depth of the damage to the rock mass was reduced by 40%-60% after the double primary support method was used. 相似文献
14.
Weak rock zone (soft interlayer, fault zone and soft rock) is the highlight of large-scale geological engineering research.
It is an important boundary for analysis of rock mass stability. Weak rock zone has been formed in a long geological period,
and in this period, various rocks have undergone long-term consolidation of geostatic stress and tectonic stress; therefore,
under in-situ conditions, their density and modulus of deformation are relatively high. Due to its fragmentary nature, once
being exposed to the earth’s surface, the structure of weak rock zone will soon be loosened, its density will be reduced,
and its modulus of deformation will also be reduced significantly. Generally, weak rock zone can be found in large construction
projects, especially in the dam foundation rocks of hydropower stations. These rocks cannot be eliminated completely by excavation.
Furthermore, all tests nowadays are carried out after the exposure of weak rock zone, modulus of deformation under in-situ
conditions cannot be revealed. In this paper, a test method explored by the authors has been introduced. This method is a
whole multilayered medium deformation method. It is unnecessary to eliminate the relatively complete rocks covering on weak
rock zone. A theoretical formula to obtain the modulus of deformation in various mediums has also been introduced. On-site
comparative trials and indoor deformation modulus tests under equivalent density conditions have been carried out. We adopted
several methods for the prediction researches of the deformation modulus of weak rock zone under in-situ conditions, and revealed
a fact that under in-situ conditions, the deformation modulus of weak rock zone are several times higher than the test results
obtained after the exposure. In a perspective of geological engineering, the research findings have fundamentally changed
peoples’ concepts on the deformation modulus of weak rock zone, provided important theories and methods for precise definition
of deformation modulus of deep weak rock zone under cap rock conditions, as well as for reasonable engineering applications. 相似文献
15.
Planation surfaces on the Tibet Plateau, China 总被引：1，自引：0，他引：1
A planation hypothesis is proposed to explain landform evolution of the Tibet Plateau. A denudation threshold （T）, the maximum potential denudation rate for a certain type of rock, is introduced to explain the combined effects of lithology and tectonics on landform evolution. If the tectonic uplifting rate （U） is equal to or less than the threshold rate （U ≤ T）, the tectonic uplifting and terrain denudation are in dynamic equilibrium, and landforms are in a steady state. The end product should be planation surfaces whether the original landforms are flat plains or deeply dissected mountains. If U 〉 T, uplift and denudation are not able to reach a dynamic equilibrium state. The plateau surface is mostly underlain by soft rocks, such as the Mesozoic epimetamorphic argillites and Tertiary sedimentary rocks, while the mountain ranges comprise hard rocks, such as granite, gneiss and limestone. In soft rock regions, hills are low with a relative relief of mostly less than 100 m and the slopes are gentle at a gradient of 〈200. In contrast, hills can maintain steep slopes in hard rock regions. The Tibet Plateau has been under an equilibrium condition between tectonic uplifting and denudation except for the mountain ranges. The plateau might have reached the present altitudes before the Quaternary. 相似文献
16.
Study on Dynamic Response of the ＂Dualistic＂ Structure Rock Slope with Seismic Wave Theory 总被引：2，自引：1，他引：1
Currently, scant attention has been paid to the theoretical analysis on dynamic response mechanism of the ＂Dualistic＂ structure roek slope. The analysis presented here provides insight into the dynamic response of the ＂Dualistie＂ structure rock slope. By investigating the principle of energy distribution, it is shown that the effect of a joint plays a significant role in slope stability analysis. A dynamic reflection and transmission model （RTM） for the ＂Dualistic＂ structure rock slope and explicit dynamic equations are established to analyze the dynamic response of a slope, based on the theory of elastic mechanics and the principle of seismic wave propagation. The theoretical simulation solutions show that the dynamic response of the ＂Dualistic＂ structure rock slope （soft-hard） model is greater than that of the ＂Dualistic＂ strueture rock slope （hard-soft） model, especially in the slope crest. The magnifying effect of rigid foundation on the dynamic response is more obvious than that of soft foundation. With the amplitude increasing, the cracks could be found in the right slope （soft-hard） crest. The crest failure is firstly observed in the right slope （soft-hard） during the experimental process. The reliability of theoretical model is also investigated by experiment analysis. The conclusions derived in this paper could also be used in future evaluations of Multi-layer rock slopes. 相似文献
17.
岩坡稳定性优势面分析法--以太湖度假区休体公园渔洋山边坡为例 总被引：1，自引：0，他引：1
运用优势面理论层次分析法。确定岩坡的控稳优势面．通过对太湖度假区休体公园渔洋山边坡的研究得出F1和软弱夹层是控稳优势面。通过优势面组合分析．得出4组优势分离体。其中F1、软弱夹层和边坡临空面组合为试算安全系数最小优势分离体。最后用Sarma法进行稳定性计算．得出各种优势分离体组合模型在考虑地下水和地震加速度为0．15g的情况下均是不稳定的。结果表明，采用层次分析法对岩坡稳定性进行评价的方法是可行的。 相似文献
18.
考虑井底水平地应力、钻井流体压力及地层孔隙压力,基于单齿侵入理论推导单齿侵入井底岩石的侵深公式,建立纯滚动锥形齿、楔形齿和滚动、剪切复合运动锥形齿等牙轮钻头的钻速方程.通过实验分析刃尖角、井底液柱压力对单齿侵入深度的影响,以及转速、轴向载荷对微钻头、牙轮钻头机械钻速的影响.结果表明:随着牙齿刃尖角的增大,锥形齿和楔形齿的侵深呈指数递减趋势;随着井底液柱压力的增大,牙齿侵入深度呈指数递减趋势,其中锥形齿降低速率大.在软到中硬地层中,牙齿侵入深度大,冲击侵入、回转剪切复合破岩方式的破岩效率高;在硬度地层中,牙齿侵入深度小,纯滚动冲击侵入破岩效率高.为分析实钻时牙轮钻头的机械钻速提供计算方法. 相似文献
19.
互层倾倒是一类典型的深层倾倒模式,为准确评价其稳定性,开展互层倾倒的工程地质特性及稳定性评价研究。以雅砻江上游发育的深层倾倒体为典型实例,利用基于演化过程的研究方法,在构建倾倒体工程地质模型的基础上,从变形过程和演化阶段上定量评价斜坡整体稳定性。研究表明:互层倾倒是由块体倾覆和板梁弯曲形成的复合倾倒模式,即:硬岩发生块状-弯曲倾倒,而软岩发生弯曲倾倒;空间上,一个发育完备的倾倒体可划分为:滑动区(A区)、强倾倒区(B区)、弱倾倒区(C区)以及原岩区(D区)。基于实测数据提出的斜坡倾倒定量描述体系,可以作为岩体倾倒变形识别和变形程度分级的基本依据;时间上,互层倾倒演化过程主要经历4个演化阶段:卸荷回弹陡倾拉裂面阶段,初始变形阶段,板梁根部折断、剪切面贯通阶段以及破坏阶段,并最终转化为蠕滑-拉裂模式形成滑坡。该滑动面受强变形岩体中倾向坡外结构面控制,而并非沿最大弯折带发育;滑动区(A区)的出现意味着斜坡最终破坏的发生,对应于演化的第三阶段,为斜坡的极限平衡状态,稳定性系数介于1.0~1.05之间。基于演化过程的评价方法,能有效解决互层倾倒稳定性评价问题。 相似文献
20.
To study the tensile mechanical properties of constant resistance bolts, the RFPA(Rock Failure Process Analysis) statics software is used to perform a uniaxial tensile test on a constant resistance bolt. The numerical test results show that the plastic strain value is 12 times the magnitude of the elastic strain. During plastic deformation, the fluctuation in the stress magnitude is relatively stable, indicating that the bolt has good constant resistance characteristics. The numerical test results are in good agreement with the laboratory test results of M.C. He, and the accuracy and reliability of the numerical test method are verified. Therefore, the RFPA software with coupled static-dynamic loading is further adopted to study the supporting effects of traditional bolts and constant resistance bolts under coupled staticdynamic loading. The numerical comparison of the test results show that the constant resistance bolts can effectively control the deformation amount and rate of the laneway surrounding rock, reduce the total and rate of increase in the accumulated acoustic emissions,decrease the stress on the units in the model and protect the stability of the laneway. This paper verifies that a constant resistance bolt has better impact resistance mechanical properties than those of a traditional bolt and provides an effective way to control rock burst and soft rock that is prone to large deformation damage. 相似文献