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1.
罗长军  胡峰  张磊奇  王会午 《岩土力学》2006,27(8):1305-1311
陡坡水库存在大坝质量差、坝体发育大量裂缝、背水坡出现散浸现象、坝后沼泽化并形成一上升泉以及排水渠和鱼池有絮状析出物、渗漏量增大等问题,这些异常现象都是由坝体及坝基渗流引起的。在阐述坝体和坝基地质、水文地质条件情况下,分析了大坝渗漏成因及大坝的渗透稳定性,指出坝体实际浸润线及坝体渗漏量是不正常的,特别是1987年后当库水位高于194 m,同一库水位呈上升趋势,这是反常的。坝基实际渗漏量异常,存在管涌和接触冲刷问题,尤其库水位低至 193.84 m,坝后上升泉仍有沙沸现象。上述现象表明大坝渗流是危险的,并分析了散浸、析出物、上升泉及沼泽化、坝肩及绕坝渗漏等现象的成因。  相似文献   

2.
直接针对西安市黑河水库左坝肩渗漏这一重大工程实际问题展开研究与计算。应用三维有限差分方法对左坝肩单薄山梁的初始渗流场、蓄水后的渗流场进行了数值模拟 ,分析渗漏方式、计算相应的渗漏量 ,并通过计算说明了断层是集中渗漏通道。而后利用三维数值计算提供的水位值 ,应用极限平衡分析法 ,对左坝肩岩质斜坡稳定性进行计算与分析 ,计算结果对实际工程的决策与治理提供重要的依据。  相似文献   

3.
《地下水》2017,(2)
利用水化学资料,针对某水库下游面和右坝肩渗漏水来源采用灰色关联度分析法进行了识别,并利用水化学分析方法进行对照,结果表明:水库右坝肩渗漏水主要来自水库水绕坝渗漏,而大坝下游面渗漏水则主要来源于地下水,其通过地下水腐蚀坝体形成渗漏在坝前渗出,其灰色关联度分析结果与水化学分析得出结论一致,为水库渗漏的进一步防治提供了参考依据。  相似文献   

4.
江雄水库蓄水初期,随着库水位逐渐上升,观测孔内水位高,坝下游陆续出现的渗漏量不断增大,量水堰最大渗漏量达到300 L/s的异常现象,影响大坝安全。通过大坝监测系统、电法探测、连通试验等成果,分析了坝基、绕坝、溢洪道、输水洞等渗漏主因,查找到主要渗流通道,为大坝堵漏处理方案设计提供了决策依据。还提出了安全渗流对保护下游生态有巨大作用的观点。  相似文献   

5.
徐宗昌 《地下水》2012,(5):212-214
南沟门水库位于陕北黄土高塬南部的黄土梁峁区,坝基为二迭系砂岩夹泥岩、第四系湿陷性黄土及砂砾石等。左坝肩主要工程地质问题是基岩强风化带的渗透问题,防渗帷幕深入岩面以下30 m;坝基存在表层堆积的砂壤土、黄土、古土壤的湿陷问题和下部砂砾石层、基岩强风化带的渗透问题,对湿陷性土层进行工程处理或清除,对砂砾石层采用结合槽截渗处理,防渗帷幕垂直厚度应大于25 m;右坝肩存在斜坡表面土层的湿陷性问题和沿三级阶地砂砾石层、基岩强风化带的绕坝渗透问题,建议翻碾处理湿陷性土层,用砼墙对砂砾石层进行截渗处理,防渗帷幕应深入岩体表面以下20 m。  相似文献   

6.
采用综合物探等方法对南京赭山头水库长期存在的渗漏问题进行探测,在物探探测渗漏区结合地质钻探确定大坝的渗漏通道,对存在渗漏通道的左右坝肩部位,采用薄壁混凝土防渗墙和帷幕灌浆的方法进行防渗处理,经过汛期高水位的检验,水库多年存在的渗漏险情得到了根本解决。  相似文献   

7.
某坝基为砂卵石基础,其下为强风化基岩,坝基渗漏和左右岸绕坝渗漏是该水库坝基存在的主要地质问题。为此,采取了塑性混凝土防渗墙与双排帷幕灌浆相结合的综合防渗措施。为了检测水库坝基及塑性混凝土防渗墙施工质量,防止水库正常蓄水后发生渗漏,选用了高密度电法进行无损检测。工程采用温纳施伦贝尔法观测,分别采用5m和10m电极间距,电极数60个,剖面数16。依据5m和10m道距实测视电阻率剖面与反演结果的解释,对水库坝基和防渗墙的工程质量进行了评价,认为-25m桩号塑性混凝土防渗墙可能存在渗漏问题,-80m桩号对应一低阻异常,坝体可能存在渗漏通道;其余部位未发现明显异常。  相似文献   

8.
石家磨水库坝址为黑云母斑状花岗岩,位于西秦岭花岗岩体西北部,岩性单一,岩体完整性较差。在左坝肩发生的倾倒滑移现象对坝肩风化、稳定、渗漏带来一系列不良影响。为  相似文献   

9.
《地下水》2020,(4)
三宝水库区域出露地层主要为三叠系下统夜郎组,以泥岩和灰岩互层为主,岩溶十分发育,导致水库渗漏问题突出。在大量工程地质调查与测绘、钻探、物探等技术手段基础上,对水库渗漏条件及渗漏通道进行研究。研究表明:三宝水库库首存在绕坝渗漏和深部岩溶管道渗漏的可能,水库左岸存在地下分水岭且高于正常蓄水位,无渗漏之忧,水库右岸向低邻谷渗漏可能性较大,库盆通过落水洞向远距离深切割侵蚀基准面渗漏的问题突出。  相似文献   

10.
受右坝肩正断层F2的影响,某水库岩溶发育,一直存在渗漏问题,经多处防渗处理,问题依然存在且日趋严重。本文综合采用流场法、自然电场法、高密度电阻率法对该水库渗漏进行了探测。发现老隧洞封堵质量较差,存在渗漏问题,并导致其下游侧坝体集中渗漏和大面积散浸;大坝坝体中部存在从上游坝坡至下游渗漏通道,是坝体下游二级坝坡出现散浸的主要原因;大坝右岸低矮山体存在渗漏入口,并可能与下游山脚的泉水点相连通;大坝右坝肩F2断层带防渗性差,存在与下游断层露头集中渗漏点相通的渗漏通道。此次探测结果表明:综合物探法能较准确获得水库渗漏源、渗流通道等位置信息。  相似文献   

11.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

12.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

13.
郯庐断裂南段研究进展与断裂性质讨论   总被引:13,自引:3,他引:13  
据1:5万区域地质调查和专题研究资料,就郯庐断裂带是否南延与消失的原因,其与大别—苏鲁造山带交截形成的假位错效应,以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上,讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。  相似文献   

14.
塘口水电站大坝基础座落在断层和裂隙较发育的龟裂纹灰岩上,岩体完整性差、透水性强,多年运行后,大坝灌浆廊道和排水廊道出现多处集中性漏水,为确保大坝安全和电站正常发电,根据渗漏性质和成因,采用对灌浆廊道补充帷幕灌浆,对排水廊道进行固结+帷幕+回填灌浆。通过灌浆处理后,效果良好,表明灌浆工程有效的将导致坝基渗漏的上下游的裂隙通道封闭,并顺利的经受了随后的汛期洪水考验,大坝安全得到保障。  相似文献   

15.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

16.
In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix.  相似文献   

17.
某高速公路下伏煤矿采空区稳定性分析   总被引:10,自引:0,他引:10  
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。   相似文献   

18.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

19.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

20.
Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base.  相似文献   

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