采用钻孔倾斜仪监测滑坡深部水平位移方法和仪器的研究

介绍了目前滑坡深部水平位移钻孔倾斜仪人工监测方法存在的问题,钻孔深部位移自动化监测通信方法的选择。地质滑坡灾害监测中广泛使用钻孔倾斜仪,介绍了CZ-2型钻孔倾斜仪的构成及现场测试方法。     

基于新型仿生智能方法的边坡变形位移预测

边坡地变形,具有高度复杂的非线性演化特征。将BP神经网络和免疫克隆算法改进并集成结合,提出一种新型的仿生智能方法,即免疫克隆神经网络。并利用其强大的非线性拟合能力,对边坡进行变形位移的预测。结果表明,此方法拥有较高的预测精度,为边坡变形位移的预测提供了行之有效的途径,从而为边坡稳定性判别和滑坡预报提供了可靠的分析依据。     

考虑位移的土压力模型在横向承载桩分析中的应用

桩与地基土之间的相互作用是横向承载桩研究的重要组成部分,相互作用的土反力是挠度和深度的非线性函数,即桩的变形和受力之间呈非线性变化,这种非线性导致了横向承载桩的分析计算十分繁杂。针对问题研究的复杂性,从考虑位移的朗肯土压力理论入手,根据桩出现挠度后引起周边土体的位移量,推导出桩周土反力表达式,在不引入任何地基模型的条件下计算桩身任意深度处基于桩体位移的土反力,简化了问题的分析过程。通过设定算例进行分析,所得出的结果与p-y曲线结果以及实际情况一致,证明了该计算方法的合理性。     

辽宁省东沟平原的演化与砂金成矿关系探讨

辽东半岛自晚白垩世以来,长期处于抬升剥蚀阶段,地形向准平原化,自晚更新世起发生多次海侵、海退作用,在黄海沿岸形成断续的滨海平原;数个滨海平原中以东沟滨海平原准平原化最好。其第四纪沉积物最全,厚度大,砂金成矿条件最好,对辽东半岛黄海沿岸砂金的供源条件、成矿环境的研究,并与国外特大型滨海砂金矿床的成矿地质条件对比认为,东沟滨海平原具有形成大型特大型滨海砂金矿床的成矿地质条件,此外,东沟平原从丘陵到浅海具有沟谷砂金、河床砂金、滨海砂金、浅海砂金的成矿条件,砂金潜在远景较大。     

灵武煤田煤中镜质组与丝质组的甾萜类化合物对比研究

本文对灵武煤田含煤岩系延安组煤岩显微组分的甾萜类化合物作了对比研究．结果表明,同一沉积环境中镜质组与丝质组的甾萜类化合物特征及不同沉积环境中同一显微组分（镜质组或丝质组）的甾萜类化合物特征有着规律性的变化．     

滑裂面形状对挡土墙主动土压力的影响

滑裂面的准确选取对挡土墙稳定性分析有重要影响。基于塑性极限分析理论,分别推导了直线和对数螺旋线滑移模式下挡土墙主动土压力的计算公式,通过算例对比分析研究了平面滑裂面和对数螺旋滑裂面主动土压力的特点。研究结果表明:直线滑裂面为对数螺旋滑裂面的一种特例,随着滑裂面曲率增大,主动土压力合力作用点逐渐上移,主动土压力合力略有增加,但对墙趾的弯矩显著增加,不利于挡土墙稳定性;挡土墙各参数对直线滑裂面主动土压力合力作用点有不同影响,随着填土内摩擦角、挡墙倾角、填土倾角的增大而上移,随着墙土间摩擦角、黏聚力与容重挡土墙高度的乘积之比的增大而下移,合力作用点位置大致在0.2~0.4倍墙高处,说明主动土压力的非线性分布。研究结果对准确选取滑裂面形状计算挡土墙主动土压力有实际工程应用价值。     

基于全耦合的地表径流与土壤水分运动数值模拟

针对降雨径流从坡面流下的过程中会发生下渗,导致土壤水非饱和带含水率增大这一动力学过程,从物理机制上对土壤水和地表水进行耦合,将二维平面地表水模型叠置在土壤水模型的顶部,对土壤水、地表水模型进行相同的空间和时间离散,在模型的计算过程中通过达西流关系对两者之间的水量交换进行计算(双层结点法耦合)或整合离散方程的整体法进行耦合。通过对两种耦合方法的比较以及与前人的实验结果对比,该模型与耦合方法能够准确地模拟和预测地表径流与土壤水分运动过程。研究结果可为分析地表水流与饱和-非饱和带水分与溶质耦合机理提供理论支持。     

西藏大冈底斯北部金属矿床成矿系列研究

依据近年西藏自治区矿产资源大调查的资料与西藏自治区矿产资源潜力评价研究获得的系统、详细的矿产资源资料,编写论述了西藏大冈底斯北部(包括班公湖-怒江成矿带、北冈底斯成矿带、中冈底斯成矿带三个成矿带)的矿产地质特征及成矿分布规律与成矿系列。班公湖-怒江成矿带包括燕山早期(洋盆形成时期,如东巧铬矿)及燕山中晚期(陆内俯冲挤压时期,如屋索拉金矿)岩浆作用有关矿床成矿系列和那曲-洛隆盆地与喜马拉雅期流体作用有关(如纳多弄铅矿)矿床成矿系列;北冈底斯成矿带矿床主要分布在申扎—嘉黎一线的北部地区(亦称冈底斯北矿带),包括玉古拉镍矿(燕山早期,岩浆岩型)、舍索铜矿(燕山中晚期,矽卡岩型为主)、尤卡朗-昂张铅矿(燕山中晚期,热液型为主)、俄龙呷砷矿(燕山晚期—喜马拉雅早期,流体-改造型为主)四个地区不同类型矿床成矿系列;中冈底斯成矿带包括近东西向两个成矿亚带,北边为革吉-雄巴-文部成矿亚带燕山中晚期(如尕尔铜金矿)及狮泉河-申扎弧-盆系演化期岩浆热液成矿作用的矿床成矿系列,南边为朗久-塔诺错-纳木错成矿亚带喜马拉雅中晚期(如甲岗钨钼铋矿)岩浆热液成矿作用的矿床成矿系列。     

Air-sea interaction over the tropical Indian Ocean during several contrasting monsoon seasons

Monthly mean anomaly fields of various parameters like sea surface temperature, air temperature, wind stress, effective radiation at the surface, heat gain over the ocean and the total heat loss between a good and bad monsoon composite and the evaporation rates over the Arabian Sea and southern hemisphere have been studied over the tropical Indian Ocean. The mean rates of evaporation on a seasonal scale over the Arabian Sea during a good and bad monsoon composites were equal (about 2·48 × 10¹⁰ tons/day). The evaporation rates over the southern hemisphere were greater during all the months. The mean evaporation rates over the southern hemisphere on a seasonal scale for the good and bad monsoon composites were 4·4 × 10¹⁰ and 4·6 × 10¹⁰ tons/day respectively. The maximum evaporation rates over the southern hemisphere were observed in August. The anomalies of wind stress, effective radiation at the surface and the heat gain over the ocean also exhibit large variations in August, as compared to other monsoon months.     

Intra-seasonal variations of kinetic energy of lower tropospheric zonal waves during northern summer monsoon

Space spectral analysis of zonal (u) and meridional (v) components of wind and time spectral analysis of kinetic energy of zonal waves at 850 hPa during monsoon 1991 (1st June 1991 to 31st August 1991) for the global belt between equator and 40°N are investigated. Space spectral analysis shows that long waves (wavenumbers 1 and 2) dominate the energetics of Region 1 (equator to 20°N) while over Region 2 (20°N to 40°N) the kinetic energy of short waves (wavenumbers 3 to 10) is more than kinetic energy of long waves. It has been found that kinetic energy of long waves is dominated by zonal component while both (zonal and meridional) the components of wind have almost equal contribution in the kinetic energy of short waves. Temporal variations of kinetic energy of wavenumber 2 over Region 1 and Region 2 are almost identical. The correlation matrix of different time series shows that (i) wavenumber 2 over Regions 1 and 2 might have the same energy source and (ii) there is a possibility of an exchange of kinetic energy between wavenumber 1 over Region 1 and short waves over Region 2. Wave to wave interactions indicate that short waves over Region 2 are the common source of kinetic energy to wavenumber 2 over Regions 1 and 2 and wavenumber 1 over Region 1. Time spectral analysis of kinetic energy of zonal waves indicates that wavenumber 1 is dominated by 30–45 day and bi-weekly oscillations while short waves are dominated by weekly and bi-weekly oscillations. The correlation matrix, wave to wave interaction and time spectral analysis together suggest that short period oscillations of kinetic energy of wavenumber 1 might be one of the factors causing dominant weekly (5–9 day) and bi-weekly (10–18 day) oscillations in the kinetic energy of short waves.