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1.
将数值模拟及统计物理学中的方法引入滑坡预测预报研究,考虑降雨等影响因素的作用,进行滑坡临滑预报.以汉江某滑坡为例,运用边坡稳定模拟分析软件(Geo-slope)进行分析计算,计算过程中主要采用了Janbu法,根据得出的安全系数对边坡的稳定性进行分析评价.根据模拟结果,在可能发生滑坡的坡体布置观测点,利用观测得到的位移及降雨量数据绘制拟合曲线图,研究曲线的变化规律,得出滑动与降雨量的关系,进行滑坡发生时间的预报.研究结果表明降雨量的急剧突变是滑坡发生的前兆,可以用来进行滑坡的短期和临滑预报.且该方法所用理论简单易懂,计算理论和方法具有很强的可操作性.  相似文献   

2.
针对山西某滑坡的边界条件,形态特征、结构特征、变形趋势,根据该滑坡体垂向上大致分为第四系全新统和上更新统、石炭系中统本溪组和上统太原组、奥陶系中统马家沟组等三层,前缘由于长年遭受河水冲剧,使滑坡体前缘临空,滑坡是由土体的自重、其上加载、各种动力作用、前缘临空、降雨和地下水等因素影响而形成,按变形阶段该滑坡处于蠕滑变形拉裂阶段,变形破坏形式为滑坡体沿底部基岩产生蠕滑,经过滑坡变形宏观分析、滑坡变形监测、滑坡稳定性计算及处置方案探讨,提出整体搬迁避让方案.  相似文献   

3.
应用一维回归分析预测新滩滑坡变形的发展趋势,求得各阶段的累积位移一时间函数,并进一步求得变形加速度和变形速度随时间变化的函数关系。通过具体分析,认为变形加速度可作为蠕变滑坡的一个临滑预警指标,并将新滩滑坡临滑预警指标定为7.5 mm/月2。  相似文献   

4.
本文研究了龙羊峡附近黄河右岸超固结粘土中一个巨型滑坡群的地质背景、发育特征和形成机制,对滑动面的发展贯通过程给予了关注,指出滑动面是由坡脚附近的顺层滑移、坡顶沿陡倾节理拉裂和滑体中部最后剪断而产生的,累进性破坏在这个过程中起了重要作用。根据地质调查资料和相关分析,提出了斜坡失稳的临界拉裂面深度和临滑前兆及其在监测预报中的意义。最后还简要讨论了滑坡高速远滑的原因。  相似文献   

5.
滑坡地质灾害远程实时监测预报技术与工程应用   总被引:1,自引:0,他引:1  
针对传统滑坡地质灾害监测预报技术存在的问题,提出"滑坡发生的充分必要条件是滑动力大于滑动面抗滑力,并将滑动力的变化作为滑坡监测预报主要参数"的学术思想。以工程边坡为研究背景,开发滑坡超前滑动力物理模拟实验、工程灾害物理模型实验等系统。采用室内和现场测试、物理和数值模拟等综合研究方法,建立力学模型,推导了相关公式,研发恒阻大变形缆索及其滑坡地质灾害防治—加固—监测—预报一体化控制技术。研发基于滑动力变化的滑坡地质灾害远程监测预报新技术及装备系统,通过大量实测曲线分析,总结四种相应的滑坡预警模式。结果表明,自2006年以来,该项技术已在露天煤矿和金属矿开采、西气东输、高速公路等工程边坡及其他自然边坡中成功推广应用,取得显著的经济和社会效益。  相似文献   

6.
在基于滑坡变形的专业监测预警工作中,滑坡后缘裂缝附近会设置多个变形监测点进行位移监测,以覆盖关键变形区域,从而确保监测数据的完整性和可靠性,并基于可靠的预警方法对滑坡变形进行预警。但现有监测预警信息的发布仅根据单点变形数据进行预警,未进行多源数据融合的监测数据综合研判,无法反映出滑坡整体发展趋势,且很可能因为单点监测数据的异常造成误报。本文采用一种多源数据融合方法,通过综合多个滑坡监测点位所采集的变形数据,从整体监测数据的位移切线角度判断滑坡是否已经进入临滑阶段,并赋予各监测点位和预警等级对应的重要性权重系数,计算出滑坡进入临滑阶段的概率,当此概率大于或等于50%时,即可认为滑坡进入临滑阶段,并以此作为预警信息发布的依据。以贵州兴义龙井村岩质滑坡预警实例进行检验发现,该融合方法可实现对误差信息的剔除和有效信息的融合,提高预警信息发布的准确性,具有较好的工程应用价值。  相似文献   

7.
结合滑坡实例,从滑坡地质环境出发,通过对滑坡变形特征机制和稳定性分析,认为前缘的临空面,坡体倾向与基岩面基本一致以及暴雨是诱发该滑坡的主导因素,并根据具体工程对治理方案进行了比较,提出了合理的治理方案。  相似文献   

8.
一种典型黄土滑坡的滑距预测方法   总被引:10,自引:2,他引:10  
针对“典型黄土滑坡”的特征,如分布于黄土台塬(高阶地)边;具有“上部黄土,下部基岩”的坡体结构;台塬面相对平整,且长期进行农业灌溉(大于15年);滑动体沿黄土下部隔水层,基岩顶部或基岩内部软弱层面滑动;台塬边无阻碍滑动体滑出的障碍物,即具有良好的临空条件;滑坡发生在无地震活动期,或说滑坡由自身重力、降雨、地下水及冻融作用而产生等状况收集了20组与滑坡滑动距离有关的资料,以多元回归分析理论为基础,建立了滑距预测模型。该模型图具有较强的针对性和较小的适用范围,并考虑了多种影种因素,故具有较高的准确性和广泛的实用性。  相似文献   

9.
受三峡水库蓄水影响,大量的涉水老(古)滑坡发生复活变形,采用地表位移监测和数值模拟研究了滑坡的变形机理和稳定性,取得了以下认识:①旧县坪滑坡在重力和库水等因素下,下滑段不断挤压阻滑段而发生推移式蠕滑变形.②库水下降是旧县坪滑坡变形的主要因素,降雨的影响有限,起主推作用.滑坡变形较大的月份主要集中在1-7月库水下降及其影...  相似文献   

10.
白龙江流域坪定-化马断裂带内发育大量滑坡,已发生了多起重大滑坡灾害.大小湾滑坡位于白龙江左岸,为典型的活动断裂带蠕滑型滑坡.近年来受集中降雨、构造活动等因素影响,老滑坡局部出现复活迹象,处于不稳定状态.本研究通过地表变形监测、野外现场调查、遥感影像解译等,对大小湾滑坡的地质环境条件、发育特征和活动特性进行研究.结果表明,滑坡活动的整体性不明显,但分块差异性活动突出.根据运动和变形特征,将滑坡分为5个区域:中部的两处次级滑块、中部次级黄土滑坡及前缘复活的两个滑块.其中,中部的次级滑块陡坎极度发育,堆积大量基岩碎石块;临江前缘活动最为强烈,坡体破碎,裂缝发育,路面鼓胀塌陷严重.在未来的变形和运动中,前缘滑块极有可能在降雨的诱发下继续发生变形,形成滑坡堵江灾害链,严重威胁滑坡上游村镇和下游舟曲县城居民的生命财产安全,灾害风险极为严峻.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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