用信息论方法对铜川市区斜坡稳定性评价预测

本文依铜川市区滑坡现象为实例，采用信息论法基本原理，对其区域斜坡稳定性进行了评价预测，得到了与斜坡破坏实际情况基本吻合之结果。     

湖南石门元家台滑坡成因机制及稳定性分析

元家台滑坡位于石门县皂市水库北西侧,现今仍威胁当地10户50余人的生命和财产安全。分析了元家台滑坡的成因机制:斜坡自身稳定性较差,长期降雨和人类活动等因素的共同作用促成了滑坡的发生;利用滑体岩土样品的实验分析数据,结合滑坡形成机制,计算分析了不同工况下元家台滑坡的稳定性:工况一(自重+地面荷载)处于基本稳定状态,工况二(自重+地面荷载+暴雨)为不稳定状态,存在再次滑动可能。     

基于多重分形特征和分项组合预测联合响应的滑坡预警预测研究

为准确掌握滑坡变形发展规律,基于滑坡变形监测成果构建滑坡预警预测模型,即先利用MF-DFA模型开展滑坡变形数据的多重分形特征分析,并进一步利用M-K分析构建双重判据（Δa指标判据和Δf(a)指标判据）进行滑坡预警研究;另外,在利用集成经验模态分解法对滑坡变形数据信息进行分离处理基础上,通过GOA-RNN-CT模型实现滑坡变形的分项组合预测。结果表明,h(q)值随波动函数q值减小而减小,说明滑坡变形数据具有多重分形特征,且预警分级研究表明,滑坡预警等级为Ⅱ级,即滑坡变形趋向不利方向发展;同时,通过变形预测分析认为,分项组合预测在滑坡变形预测中具有较优的预测效果和稳定性,且外推预测结果显示,滑坡变形会继续增加;最后,将多重分形特征研究结果和变形预测分析结果进行联合响应综合得出,滑坡现有预警等级相对不利,且后续变形仍会进一步增加,趋向不稳定方向发展,建议对滑坡采取必要防治措施。     

某高速公路滑坡的数值模拟及后缘坡体稳定性分析

通过对诸永高速公路台州段1#滑坡(K120 085～K120 169)工程地质特征的分析,指出沿线区存在很多因修建公路引发的工程滑坡问题,然后采用边坡稳定性FLAC/Slope分析软件,对滑坡滑动前、后工况下稳定性进行数值模拟,并对滑移后的后缘坡体稳定性进行了数值分析.剪应变率云图和稳定性分析结果表明,滑动后的后缘坡体仍处于不稳定状态,又形成了新的滑坡体.     

兴仁“6·10”彭家洞高速滑坡运动特征与形成机理

2021年6月10日20时30分左右, 贵州省兴仁彭家洞发生高速滑坡, 滑坡体高速运动沿途铲刮坡面崩塌堆积体, 造成3人遇难, 18栋房屋损毁。通过对滑坡发生前后影像资料遥感解译、灾害发生现场详细的地质调查及室内综合分析等技术手段, 对彭家洞滑坡的特征进行了详细描述, 阐明了滑坡发生的运动特征与形成机理。研究表明: 斜坡地形"上陡-中缓-下陡"与岩土结构"上硬下软"是滑坡形成的内在因素, 人类工程活动、强降雨的饱水加载和下渗软化作用是滑坡形成的外在因素; 滑坡平面形态呈折线形, 根据运动特征和堆积结构将滑坡分为滑源区(Ⅰ)、铲刮-流通区(Ⅱ)、铲刮堆积区(Ⅲ)3个区; 滑坡是由危岩带形成、滑坡孕育及斜坡失稳3个阶段孕育形成的挤压-推移式高速滑坡。研究结果对贵州类似的斜坡地带及岩土结构区域开展防灾减灾工作具有较强的指导作用。      

土坡稳定性的极限分析方法

本文应用塑性力学中的极限分析法原理，建立了滑动面为折线时的土坡稳定性极限分析公式。通过工程实例证明，该公式具有使用简便、可靠性强等优点。它对于评价斜坡的稳定性，合理地进行滑坡治理等，都具有实际意义。     

面向区域滑坡易发性精细化评价的改进斜坡单元法

易发性评价是区域滑坡灾害风险预警与稳定性分析的基础,针对乡镇尺度的大比例尺精细化滑坡易发性评价,传统基于水文学和地貌学的斜坡单元划分方法难以满足评价精度。针对以上问题,以重庆市万州区大周镇为实例验证对象,形成了适用于精细化评价的改进斜坡单元划分方法。首先从斜坡地质环境孕灾规律出发,综合考虑地形地貌、物质组成、斜坡结构和灾害类型的均一性要求,提出了基于斜坡地质环境一致性的改进斜坡单元划分方法,选择重庆市万州区大周镇为实例验证对象,并与水文分析法、曲率分水岭法进行了对比分析。结果表明：(1)改进斜坡单元法划分的评价单元大小均匀性较好,未出现细碎单元或畸形长条状单元;(2)评价单元的总体形态特征更为合理,形态指数集中在1～2之间,呈现圆形或正方形斜坡形态;(3)改进斜坡单元划分的结果与已有灾害边界范围的叠加重合度最高,能更好地体现滑坡易发性评价或稳定性分析物理意义。研究结论对提高区域滑坡易发性评价的准确性与精度具有重要借鉴意义。     

基于尖点突变理论及非趋势波动分析的滑坡稳定性及变形特征研究

以尖点突变理论及非趋势波动分析为基础,构建滑坡稳定性及变形趋势判断模型。首先利用尖点突变理论对滑坡整体稳定性进行评价,并进一步探讨滑坡的分阶段稳定性特征;再利用非趋势波动分析判断滑坡累计序列和速率序列的整体及分阶段变形趋势,并与稳定性分析结果进行对比。实例表明,两种分析方法的结果具有较好的一致性。在分阶段研究中,等时段和递增时段的分析结果具有明显差异,说明阶段分解方式对结果的影响较大,且以递增时段分析结果的规律性更强。     

玉树县结古镇某水电站滑坡成因分析及治理探讨

首先根据滑坡病害段的地形地貌、地层岩性和变形活动等特征,对滑坡的形成机制进行了分析,其次对其滑带土的物力力学参数及以及滑坡的稳定性进行了评价,最后根据滑坡机理及稳定性提出了截排水、抗滑桩支挡和锚索框架加固等综合治理措施,可为类似工程治理提供借鉴。     

基于C、φ值的滑坡稳定性及敏感性分析

滑带抗剪强度参数(C、φ值)是影响滑坡体稳定性的主要因素,本文以某滑坡为例,根据岩土物理力学性质指标的试验结果以及滑坡稳定性反演分析结果,采用传递系数法,分不同的工况条件进行滑坡稳定性计算。以C、φ值作敏感性分析,研究其对滑坡稳定性的影响,为下步防治提供依据。     

相位在地震勘探中的用途及研究

主要应用傅立叶变换方法计算各种信号的振幅谱和相位谱。通过对一个球形信号进行傅立叶正反变换，发现用相位谱恢复的图形轮廓比振幅谱恢复的图形轮廓清晰。相位在信号分析中，特别是对于所要研究的地震信号尤为重要。但是，相位谱的常规计算及显示方法很难满足解释要求，就通过改善相位谱的常规计算及显示方法，并用一个简单地震模型例子，说明了改善后的相位谱更容易被解释和利用。     

Extraction method of component waves in full waveform acoustic data and its application

In conventional slowness-time coherence(STC)method,slowness and time need to be searched at the same time,which limits the precision and lowers the efficiency.The dichotomy method combined with slowness-time coherence algorithm aims to enhance the efficiency of data processing and to improve the precision.The algorithm changes the searching pattern of conventional slowness-time coherence method to acquire the slowness of component waves in array acoustic logging data.Based on energy ratio of short time window versus long time window and slowness-time coherence method,the algorithm first acquires the arrivals of the component waves using energy ratio of short time window versus long time window method.It then uses the calculated results as the arrivals in conventional slowness-time coherence method,so the slowness-time two-dimensional searching process is simplified to slowness searching process.Based on dichotomy method,the searching pattern is further optimized in replace of the ergodic searching pattern in conventional slowness-time coherence method,which means that as the iteration proceeds,the current searching interval is reduced to half of the former,so the number of searching times is decreased.The dichotomy method combined with slowness-time coherence algorithm is applied to well L in the data processing.Compared with conventional slowness-time coherence method,for compressional wave,the searching efficiency of the algorithm is 4.53 times better,while for Stoneley wave,the searching efficiency is 1.85 times better.Compared with conventional logging data,the average absolute error of the results of the dichotomy method combined with slowness-time coherence algorithm is 1.14μs/ft smaller than that of the conventional method,while the average relative error is 1.2 percent lower.The dichotomy method combined with slowness-time coherence algorithm shows good results in its application,which can enhance the processing efficiency remarkably while getting reliable results at the same time.     

华南山间谷地型软土的特性及处理方法

文章对华南山间谷地型软土的特性、勘察方法进行了分析 ,并对工程施工中软土的处理方法进行了一些探讨 ,提出应用多种手段准确勘察软土特性和多种软土地基处理方法 ,可以有效保证软土分布区域工程质量。     

水文地质调查与物探结合在石灰岩地区找水定井的应用

根据水文地质调查确定物探靶区,采用激发极化四极电测深法进行物探确定井位。实践证明,水文地质调查和物探联合定井在缺水地区寻找深层地下水方面有较强的推广利用价值。     

~1H NMR Quantification of DHA and EPA in Fish Oil

Fish oil is a popular nutritional product consumed in China. The beneficial effects of fish oil have been attributed to docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA). Hence, it is crucial to develop a rapid and precise method to determine the contents of EPA and DHA in fish oil. In this study, a rapid and accurate proton nuclear magnetic resonance method for the quantification of DHA and EPA was developed. Dimethyl terephthalate was selected as an internal standard, and the signals at 2.391 ppm for DHA and at 1.697 ppm for EPA were chosen for the quantification. Validation of the method was performed in terms of specificity, precision, and stability. The results indicated that the method was precise and in line with the China Food and Drug Administration guidance. The method has been successfully applied to characterize fish oil capsules obtained from four pharmaceutical companies. This study indicated that the rapid ~1H NMR method is suitable for the quality control of fish oil.     

Mechanism and forecasting methods for severe droughts and floods in Songhua River Basin in China

The influence of various factors, mechanisms, and principles affecting runoff are summarized as periodic law, random law, and basin-wide law. Periodic law is restricted by astronomical factors, random law is restricted by atmospheric circulation, and basin-wide law is restricted by underlying surface. The commensurability method was used to identify the almost period law, the wave method was applied to deducing the random law, and the precursor method was applied in order to forecast runoff magnitude for the current year. These three methods can be used to assess each other and to forecast runoff. The system can also be applied to forecasting wet years, normal years and dry years for a particular year as well as forecasting years when floods with similar characteristics of previous floods, can be expected. Based on hydrological climate data of Baishan (1933-2009) and Nierji (1886-2009) in the Songhua River Basin, the forecasting results for 2010 show that it was a wet year in the Baishan Reservoir, similar to the year of 1995; it was a secondary dry year in the Nierji Reservoir, similar to the year of 1980. The actual water inflow into the Baishan Reservoir was 1.178 × 10 10 m 3 in 2010, which was markedly higher than average inflows, ranking as the second highest in history since records began. The actual water inflow at the Nierji station in 2010 was 9.96 × 10 9 m 3 , which was lower than the average over a period of many years. These results indicate a preliminary conclusion that the methods proposed in this paper have been proved to be reasonable and reliable, which will encourage the application of the chief reporter release system for each basin. This system was also used to forecast inflows for 2011, indicating a secondary wet year for the Baishan Reservoir in 2011, similar to that experienced in 1991. A secondary wet year was also forecast for the Nierji station in 2011, similar to that experienced during 1983. According to the nature of influencing factors, mechanisms and forecasting methods and the service objects, mid-to long-term hydrological forecasting can be divided into two classes:mid-to long-term runoff forecasting, and severe floods and droughts forecasting. The former can be applied to quantitative forecasting of runoff, which has important applications for water release schedules. The latter, i.e., qualitative disaster forecasting, is important for flood control and drought relief. Practical methods for forecasting severe droughts and floods are discussed in this paper.     

沂源煤田鲁村井田山西组层位的发现及其地质意义

通过采用地面物探、钻探和井下巷探、钻探相结合的综合勘探方法,对鲁村井田深部进行了补充勘探,并对井田以往地质资料进行了重新对比分析,发现该井田-400～-1 300 m的埋深范围内不但存在以往认为已被剥蚀缺失的太原组上部地层,还保存了较完整的山西组,尤其是在该段地层中新发现了5个局部可采煤层,为井田增加了资源储量、延长了服务年限。填补了沂源煤田太原组上部和山西组含煤地层资料的空白。     

自由设站法在城市测量中的应用

实际测量工作中,经常会碰到控制点丢失或不通视情况,本文介绍了自由设站法在城市中的应用。实践证明,该方法现场操作简单、精度可靠,有检核条件,完全能满足工程测量的精度要求。     

Comparison of finite difference and pseudo-spectral methods in forward modelling based on metal ore model of random media

With more applications of seismic exploration in metal ore exploration,forward modelling of seismic wave has become more important in metal ore.Finite difference method and pseudo-spectral method are two im-portant methods of wave-field simulation.Results of previous studies show that both methods have distinct ad-vantages and disadvantages:Finite difference method has high precision but its dispersion is serious;pseudo-spectral method considers both computational efficiency and precision but has less precision than finite-diffe-rence.The authors consider the complex structural characteristics of the metal ore,furthermore add random media in order to simulate the complex effects produced by metal ore for wave field.First,the study introduced the theories of random media and two forward modelling methods.Second,it compared the simulation results of two methods on fault model.Then the authors established a complex metal ore model,added random media and compared computational efficiency and precision.As a result,it is found that finite difference method is better than pseudo-spectral method in precision and boundary treatment,but the computational efficiency of pseudo-spectral method is slightly higher than the finite difference method.     

深地震测深在国内的发展与应用现状研究

通过关键词共现分析方法,对深地震测深技术在国内的发展及其应用现状进行研究。结果表明,深地震测深资料处理以二维动力学射线追踪的正反演方法为主,三维地壳结构模型的构建方法则以改进的克里金插值方法为主;深地震测深可用于揭示孕震构造环境,但对区域地壳结构与地震发生规律和活动性的总结较少;在地震测深成果方面,包括地壳结构类型和地壳厚度等,与地热、金属以及油气矿产资源的形成密切相关,但是目前尚未形成能够服务于矿产资源勘查的成果库和数据产品;海洋深部探测是目前深地震测深方法应用的热点,应当加强海陆联合地震观测,充分发挥两种观测模式的优势。