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1.
对东平台2017~2018年体应变、水位的观测资及降雨情况进行统计、分析,结果表明,因为钻孔条件一般,存在两段破碎带,且套管长度仅90 cm,在降雨尤其是连续降雨时,体应变及水位受到严重影响,体应变的响应时间滞后于水位变化。体应变和水位存在显著的相关性,相关系数达0.91以上,水位干扰系数最高可达10.64×10-8/cm,水位对降雨雨量的放大倍数高达103倍。与泰安台体应变进行简单的对比分析得出,相同岩性下改善钻孔环境及套管的长度可以有效减少降雨对体应变、水位的影响。  相似文献   

2.
利用合肥台、黄山台钻孔体应变2013~2015年观测资料日均值与降雨引起的地下水位变化进行相关分析,同时考虑体应变变化的滞后性,使用Matlab计算水位和体应变不同滞后时间的相关系数,确定滞后天数;扣除滞后天数,再进行回归拟合分析,消除水位干扰。鉴于水位对体应变干扰的复杂性,在运用长周期数据时,以月为窗长进行回归分析,能较好地消除水位对体应变的干扰,利于体应变的趋势性判断。  相似文献   

3.
对徐州地震台的YRY-4型分量式和TJ-2型体积式钻孔应变仪,2008—2010年的面应变原始观测曲线、年变曲线、降雨干扰曲线、气压影响曲线和固体潮汐观测结果进行了比对研究,并计算了各自的相关系数和影响系数,总结了二者的共性和差异。  相似文献   

4.
青岛台体应变短周期(小于128 min)气压系数2018-01出现阶变,通过对观测系统、台站周边施工情况、监测环境等逐项现场核实,排除观测系统、周边施工的影响。利用离散小波变换和回归分析发现,钻孔水位的气压系数与体应变气压系数同步阶变,结合台站钻孔施工当天体应变钻孔水位变化、体应变趋势变化、其他相邻台站水位气压系数变化等数据认为,台站钻孔施工是导致体应变气压系数变化的原因,并定性分析其变化机理。  相似文献   

5.
易县地震台伸缩仪曲线2019-01起加速上升,年变曲线形态出现转折变化,排查各项干扰因素并结合异常出现时间及三维模拟定量分析发现,应变模拟计算结果3.14×10-8是应变实际异常变化量6.98×10-8的一半,此次洞体应变数据异常与采石场造成的荷载环境干扰有关,但可能不仅这一干扰因素,不排除存在其他干扰源或地壳自身产生的应变变化。  相似文献   

6.
岩层倾斜对体应变受气压影响研究   总被引:1,自引:0,他引:1  
台站实测资料反映地表倾斜时,体应变气压干扰系数明显变大.通过理论计算,求出了地表倾斜度与体应变气压系数的关系,去除气压干扰后,体应变观测的固体潮汐明显改善.  相似文献   

7.
TJ-Ⅱ型钻孔体应变仪数字化观测资料分析   总被引:13,自引:6,他引:7  
对位于山东省不同地理、构造条件的4个TJ-Ⅱ型钻孔体应变仪数字化观测资料进行了分析,结果表明:4个台的体应变资料不同程度地受降雨、地下水位、气压、温度的影响,其完整性、稳定性和可靠性不同,记录地震波的能力也存在差异。  相似文献   

8.
对马陵山台洞体应变观测数据进行跟踪分析,研究降雨、气压、仪器调试、观测系统故障和仪器标定的干扰特征。研究表明,该仪器在强降雨后会趋势性下降,表现为加速向下压缩变化,大的气压波动会同步出现固体潮畸变,仪器调修和线路故障也会产生固体潮畸变,仪器标定会造成观测数据产生大幅突跳或台阶。  相似文献   

9.
九江台2008~2013年洞体温度年变化、气压骤升、集中降雨、抽水和承压含水层卸载引起洞体应变异常幅度为10-9~10-6量级,洞体应变异常机制主要为观测介质的温度效应和山体附加应力的加卸载过程,台站应变观测对局部应力场的敏感性为捕捉地震前兆异常提供了可能性。  相似文献   

10.
对泰安台不同类型钻孔应变仪的产出资料进行研究,分析分量应变仪的自检可靠性及其与体应变资料的相关性,以及在抽水干扰情况下的相关性。RZB-3仪两组互相正交的分量应变之和S1+S3、S2+S4的自检相关性达到0.999 9,其与体应变的相关性达到0.998以上。但在抽水干扰情况下,S1+S3、S2+S4自检相关性及与体应变的相关性均较差。  相似文献   

11.
以奉节新铺下二台滑坡为例, 基于GPS位移监测数据、裂缝数据、降雨量及库水位等多源数据, 总结分析了大型古滑坡的复活规律, 引入滑坡中长期预报模型, 实现了以季度或月份为时间单位的跨水文年滑坡位移预测, 并通过岩土体蠕变压缩模型, 验证了推移式滑坡后缘裂缝形成机理。结果表明: ①降雨是下二台滑坡变形的主导因素, 滑坡变形使得滑体产生裂缝并成为降雨入渗通道, 加剧了岩体破碎与软弱层软化, 降低了滑坡稳定性, 集中持续降雨可使滑坡失稳破坏; ②通过模型预测值与地表监测数据的比较, 将年降雨量作为滑坡中长期预报模型中的主控因素具有实际可操作性且有助于提高滑坡中长预报精度; ③推移式滑坡后缘裂缝由滑坡推移式位移和岩土体压缩形成, 引入蠕变压缩模型计算的裂缝宽度并和监测数据的比较说明, 蠕变压缩模型非常适合该类边坡, 同时应用岩土体蠕变压缩模型反推得到岩土体平均变形模量, 判断岩体破碎程度, 可以为滑坡稳定性分析及后续工程治理提供参考。   相似文献   

12.
The "4.20" Lushan earthquake in Sichuan province, China has induced a large amount of geological hazards and produced abundant loose materials which are prone to post-earthquake rainfalltriggered landslides. A detailed landslide inventory was acquired through post-earthquake emergent field investigation and high resolution remote sensing interpretation. The rainfall analysis was conducted using historical rainfall records during the period from 1951 to 2010. Results indicate that the average annual rainfall distribution is heterogeneous and the largest average annual rainfall occurs in Yucheng district. The Stability Index MAPping(SINMAP)model was adopted to assess and analyze the postearthquake slope stability under different rainfall scenarios(light rainfall, moderate rainfall, heavy rainfall, and rainstorm). The model parameters were calibrated to reflect the significant influence of strong earthquakes on geological settings. The slope stability maps triggered by different rainfall scenarios wereproduced at a regional scale. The effect of different rainfall conditions on the slope stability is discussed.The expanding trend of the unstable area was quantitatively assessed with the different critical rainfall intensity. They provide a new insight into the spatial distribution and characteristics of postearthquake rainfall-triggered landslides in the Lushan seismic area. An increase of rainfall intensity results in a significant increase of unstable area. The heterogeneous distribution of slope instability is strongly correlated with the distribution of earthquake intensity in spite of different rainfall conditions. The results suggest that the both seismic intensity and rainfall are two crucial factors for postearthquake slope stability. This study provides important references for landslide prevention and mitigation in the Lushan area after earthquake.  相似文献   

13.
强降水的GP分布拟合   总被引:1,自引:0,他引:1  
根据极值理论中处于重要地位的GP分布模型,讨论了模型中的形状参数、位置参数及尺度参数的算法,并将其用于拟合呈偏斜状态的月和日降水量资料中强降水部分,得到强降水发生的直观年数。  相似文献   

14.
针对2016年5月发生于秭归县西北部的谭家湾滑坡,结合卫星遥感影像、现场勘查资料以及历史资料等多源数据,初步明确了滑坡的影响区域、特征及发生时序;综合采用钻探、槽探、物探等手段,开展室内外相关实验,明确了滑坡区的地层特性以及岩土体物理力学性质指标,通过分析该区裂缝位移及GPS数据,对该边坡的变形机制进行了探讨,并对该区稳定性进行了评价。结果表明:①谭家湾滑坡属于不规则"圈椅形"中型松散层的水库下降型滑坡,滑坡区的地表形态、地质构造及岩性等因素决定了滑坡的形成和发育,库水位和降雨的共同作用激励了滑坡的变形;②滑坡根据时序共分为3级滑体,总体呈现多次、多层、相互影响的演化特点,第三级滑体具有牵引式特征;③滑坡体内地下水位随库水位下降而下降,但下降速率缓于库水位,随之坡体内水力梯度和渗透力显著变大,此时碰到强降雨,将会导致坡体地下水赋存,岩土体软化,加剧滑坡变形,须施加必要的防护措施。④稳定性分析表明,该滑坡现处于临界稳定状态,一旦发生降雨和库水位变化,局部段可能发生失稳滑动。   相似文献   

15.
Due to the special condition of provenance and disaster environment after "5·12" Earthquake, the probability and conditions of the occurrence of gully debris flow change greatly after the event, which make it difficult to prevent disaster effectively. In this study the hydrological model of ground water table in loose sediment is established. According to infinite slope theory, the safety factor of deposits is defined as the ratio of resistance force to driving force. The starting condition of post-earthquake gully debris flow is clearly studied by analyzing the effects of rainfall intensity, seismic strength, slope gradient and mechanical properties on the balance of accumulation body. Then the formulas of rainfall and aftershock threshold for starting of gully debris flow are proposed, and an example is given to illustrate the effect of rainfall, aftershocks and their coupling action on a debris flow. The result shows the critical rainfall intensity decreases as the lateral seismic acceleration and channel gradient increases, while the critical intensity linearly increases as the friction angle increases.  相似文献   

16.
The landslide hazards occurring in the complex geological genesis accumulation body are usually controlled by the coupling action of many internal and external factors. Therefore, this paper takes the dam-front Danbo accumulation body landslide of Yangfanggou hydropower station on the Yalong River as the geological prototype, and discusses the process and mechanism of slope stability degradation under the combined action of rainfall and slope construction. Based on the detailed understanding of the basic characteristics of the accumulation body, the development characteristics of the landslide and the construction situation of the slope engineering, the study conducted correlation analysis between rainfall and landslide displacement, the physical and mechanical tests of all types of rocksoil masses, and the numerical simulation testing of seepage field variation of the landslide section. It is found that the special slope structure and material composition of the old landslide accumulation layer on the upper part of the Danbo accumulation body are the internal factors for the occurrence of thrust loadinduced landslide, and the construction of the slope engineering not only creates free space conditions for sliding, but also provides channels for the infiltration of rainfall into the slope after confluence, which is an external factor that caused the mechanical properties of the sliding zone soil to gradually weaken from the trailing edge to the leading edge. The geomechanical model of such landslide is that the active section of the trailing edge produces the "source of force", the transition section of the middle section affects the occurrence of sliding, and the anti-sliding section of the leading edge controls the occurrence of landslide hazards. The results of this research provide not only a useful supplement to the theory of landslide formation mechanisms but also a scientific basis for guiding the prevention and control of similar hazards.  相似文献   

17.
1980-2015年黄河流域降雨侵蚀力时空变化分析   总被引:2,自引:0,他引:2  
本文利用1980-2015年黄河流域及周边166个气象站点36 a的降雨资料,采用日降雨侵蚀力计算模型,对克里金插值后的栅格数据,通过利用主成分分析法、isodata聚类和最大似然法实现区域划分,并在此基础上应用重心模型研究了黄河流域降雨侵蚀力的时空变化。研究结果表明:黄河流域内不同区域的年降雨侵蚀力差异较大,最小的区域在200 MJ·mm·hm-2·h-1左右变化,最大的区域可达3000 MJ·mm·hm-2·h-1,年降雨侵蚀力具有由西北向东南递增的趋势。年降雨侵蚀力大的区域其侵蚀力值在不同年份中波动范围也大。西宁、呼和浩特等所在的一区、二区和三区的年降雨侵蚀力的重心总体上呈现向东北方迁移趋势。太原、西安所在的四区、五区其重心总体上呈现向西南方迁移趋势,其年降雨侵蚀力重心迁移范围小,重心点分布更紧密。各区域年降雨侵蚀力重心的迁移范围在空间和时间尺度上总体呈现由西北向东南方向逐渐缩小趋势。  相似文献   

18.
库岸滑坡体分布广泛,在库水位升降和降雨条件下极易失稳。三板溪水电站东岭信滑坡堆积体总方量2 000×104 m3,最大厚度150 m,2006年水电站蓄水后滑坡体开始出现大变形,每年雨季加剧。首先经野外地质勘察和十余年监测数据整理,探明了地质条件和变形规律;其次使用SEEP/W模块对不同库水位升降速率、2019年库水位结合实测降雨条件下的饱和-非饱和流进行模拟,并采用SLOPE/W分别计算不同时刻的稳定系数。分析认为东岭信为超深层滑坡,其变形过程深受库水位升降和降雨影响;滑坡体具有明显的滞水特征,渗流过程复杂;在库水位上升过程中稳定系数不断下降,而在库水位消落过程中稳定性逐渐增强;在库水位上升和强降雨量共同作用下稳定性下降很快,汛后10 d左右达到最低值,此时的稳定性最差。本研究可用于指导库水位升降和降雨条件下大型滑坡体稳定性评价。   相似文献   

19.
Observational data obtained during the TOGA-COARE IOP in the "warm pool" area of the West-ern Tropical Pacific were used to analyze some characteristics of the intraseasonal variations in the mixedlayer. The influence of westerly burst and rainfall on SST, salinity. and mixed layer depth are discussed.There are two pairs of counteracting processes in the "warm pool" mixed layer: (1) The increase of mixedlayer depth caused by local westerly bursts and the decrease of mixed layer depth caused by larger scaleeasterly relaxation;(2) the vertical mixing by local wind and the strong stratification due to rainfall in themixed layer. Some possible mechanisms through the interactions between the intraseasonal time scale varia-tions of the oceanic mixed layer and atmospheric low frequency oscillations are revealed.  相似文献   

20.
?о???2003??2006???????????Sacks????????????峱??????????????????????????峱??????????????????????仯??????????????????????????????????????????????????0.533??????亯??????????????????????????????????????????????仯????????????????????????????????????????????????????6.28??10-11/Pa??????亯?????????????????????????????????????????????????????????????????????????Ч????£????????????????????????????????????????????????????????????????????????????????????????????????????й??  相似文献   

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