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1.
利用稳态坡形类比法预测基岩岸坡的库岸再造   总被引:9,自引:0,他引:9  
水库库岸再造是水利水电工程中经常遇到的工程地质问题之一.依据库岸地质结构和岩性组合, 划分出工程地质条件相近的库岸段, 与工程地质条件相类似的稳态坡形进行类比, 确定出再造后的稳态坡形的坡角大小, 从而进行库岸再造预测.利用稳态坡形类比法对三峡库区迁建新址的基岩库岸进行了再造预测, 定量预测出三峡水利枢纽工程建成蓄水后, 巫山县城新址基岩库岸最终再造带宽度在40166m之间, 预测结果可以用来指导新城的规划与建设.   相似文献   

2.
利用稳态坡形类比法预测基岩岸波的库岸再造   总被引:3,自引:0,他引:3  
水库库岸再造是水利水电工程中经常遇到的工程地质问题之一。依据库 岸地质结构和岩性组合,划分出工程地质条件相近的库岸段,与工程地质条件相类似的稳态坡形进行类比,确定出再造后的稳态坡形的坡角大小,从而进行岸再造预测,利用稳态坡形类比法对三峡库区迁建新址的基岩库岩进行了再造预测,定量预测出三峡水利枢纽工程建成蓄水后,巫山县新址基岩库最终再造带宽度在40-166m之间,预测结果可以用来指导新城的规划与建设。  相似文献   

3.
巫山县城新址位于西坪和大宁河两岸.组成该库段的基岩主要为泥岩、粉砂岩、泥灰岩等,岩性较软弱,且地质构造变动强烈,褶皱、断裂发育,岩层破碎,崩塌、滑坡分布较多,库岸再造问题严重;同时,岸坡再造又严重影响着新县城的规划和库岸的防护.因此把稳态坡形类比法应用于巫山县城新址基岩岸坡的再造预测,定量预测库岸的最终再造宽度,以指导新城的规划与建设.  相似文献   

4.
长江三峡工程库区巴东新城址环境工程地质预测   总被引:2,自引:0,他引:2  
巴东县城新址是长江三峡工程库区移民城镇环境工程地质问题较突出的场址之一, 主要环境工程地质问题是古滑坡的失稳和库岸再造。在查清地质环境条件的基础上, 本文着重进行了黄土坡古滑坡、赵树岭古滑坡等古滑坡的稳定性预测, 并根据实测的有关参数, 采用图解法预测库岸再造宽度。在此基础上, 根据影响该区城市开发建设的主要的地质环境要素, 建立隶属函数, 采用模糊综合评判模型及算法, 给出巴东县城新址区的城市开发建设的环境地质分区评价。  相似文献   

5.
陈洪凯  赵先涛  唐红梅 《岩土力学》2014,35(4):1095-1100
水库运行期间库岸再造预测是工程地质领域的重要和热门研究课题之一。基于卡丘金法采用半经验性、半定量的模式,简化了水文地质条件的影响,并忽略了波浪对库岸的掏蚀作用等缺陷,针对土质岸坡,提出了基于浪蚀龛和土体临界高度的卡丘金修正法;建立了库岸再造稳定时限估算方法;并采用极限平衡法、卡丘金法和构建的土质岸坡再造预测方法对三峡库区奉节白马港岸坡进行了塌岸预测。计算结果表明,修正的卡丘金法的计算结果与其他两种预测方法相比偏小,但偏差在8.05 m以内,并通过现阶段库岸地质调查表明,预测结果比较符合实情。研究成果对库岸区域土地资源开发利用及防灾减灾具有积极意义。  相似文献   

6.
雅泸高速公路青杠咀特大桥泸沽岸桥台与岗子上隧道进口衔接段位于大渡河右岸上部冰积扇上,由于瀑布沟水电站的蓄水将使岸坡前缘约1/4部分没于水下。对整个岸坡影响较大的岩土体主要是由上-中更新统冰积、冰水沉积层组成的冰水堆积物,这类岩土体在水的作用下,其物理力学性质和强度将会发生显著变化,弱化工程性状,从而影响岸坡的稳定性及桥台布置。可以预见,对岸坡起主要影响作用的外部条件就是水的作用,库岸再造将是影响岸坡稳定性的控制性因素。本文以岗子上隧道进口岸坡为研究对象,通过对岸坡工程地质条件、岩土体结构及物理力学特性、岸坡影响因素的分析,深入研究了瀑布沟电站水库蓄水后引起的库岸再造对岸坡稳定性的影响。并采用卡丘金法、两段法(多段法)、极限平衡分析法对库岸再造影响宽度进行预测。3种方法的预测结果表明:瀑布沟电站蓄水后该段岸坡各个不同部位均会产生不同程度的塌岸破坏。根据该库岸岸坡的结构特点和3种方法的适用条件,提出对库岸岸坡不同梯段需要采用不同的预测方法综合预测,即对于水下岸坡可按两段法预测,而对于水上岸坡可综合考虑卡丘金法和极限平衡法的计算结果。对于类似库岸岸坡的稳定性分析具有一定的指导意义。  相似文献   

7.
长江三峡工程水库塌岸与工程治理研究   总被引:14,自引:0,他引:14       下载免费PDF全文
唐辉明 《第四纪研究》2003,23(6):648-656
水库塌岸(岸坡再造)是影响三峡水库移民工程安全的重大地质灾害问题.本文在分析三峡库区塌岸特征的基础上,总结了近期库区塌岸治理工程的若干关键技术问题,论述了三峡库区塌岸预测方法.以兴山县高阳镇库岸治理工程为例,介绍了岸坡稳定性分析、岸坡再造范围预测、库岸稳定性分区和工程治理方案论证的方法、步骤和具体内容.  相似文献   

8.
三峡库区重庆段塌岸预测研究   总被引:2,自引:0,他引:2  
三峡水库蓄水将会引起库区两岸变形再造,为了研究重庆段库岸塌岸变形,通过对重庆段重点库岸段的详细地质调查,总结出重庆库岸段存在如下三种主要的塌岸模式:冲蚀磨蚀型、坍(崩)塌型、滑移型;其中冲蚀磨蚀型约占调查总长的54%,坍(崩)塌型约占42%,滑移型仅占4%左右。在调查的基础上,针对不同的库岸塌岸模式和岸坡结构,采用不同的塌岸预测方法和预测参数开展了重庆段重点库岸段的塌岸预测,得出重庆段80%的库岸再造范围在20 m以内,而再造变形范围大于20 m的库岸段大多表现为滑移型。以上为重庆段库岸塌岸的防治措施提供了理论依据。  相似文献   

9.
简述了单因变量偏最小二乘回归法的基本原理和计算步骤.针对水库库岸再造预测的特点,将三峡库区巫山县段的岩质库岸划分为漫滩段、枯-洪水位变幅带、常见洪水位以上段3种类型.建立了坡角与岩体类型、力学性质、地形地貌之间的3个偏最小二乘回归方程.计算结果表明,组成岸坡的岩体类型、性质是决定库岸再造的最主要因素,地形地貌因素次之.应用偏最小二乘回归模型,可提高库岸再造预测的准确度,为土地利用提供决策支持.  相似文献   

10.
三峡工程库区万县市移民迁建新址受多种地质环境因素的影响,主要表现为斜坡稳定、库岸稳定、地形坡度、地基土质量和水体污染等环境地质问题对新址土地开发利用的制约。本文运用损益分析方法,通过建立计算模型,对万县市迁建新址地质环境质量进行经济评价,将新址地质环境质量信息转换为城市地质环境开发利用的经济信息,为万县市的移民迁建和土地资源的开发利用提供科学的决策依据。  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.
正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the  相似文献   

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