隧道工程地质评价的内容和方法

结合工程隧道实际,首先阐述了隧道工程的基本地质环境和工程地质条件,然后针对隧道工程可能出现的不良地质现象和可采取的工程措施,从大气降水、围岩稳定、围岩压力、洞口稳定、隧道比选等角度探讨隧道工程地质评价的主要方法和一般内容,进行隧道工程地质评价,为隧道施工、支护提供了依据.     

Progress in Earthquake Science and Technology in China: Review and Prospects (Ⅰ)

In the article the author looks back the hard development course and great progress in earth quake science and technology in China during the last near a half of century and expounds the following 3 aspects: (1) The strong desire of the whole society to mitigate seismic disasters and reduce the effect of earthquakes on social-economic live is a great driving force to push forward the development of earthquake science and technology in China; (2) To better ensure people‘ s life and property, sustainable economic development, and social stability is an essential purpose to drive the development of earthquake science and technology in China; and (3) To insist on the dialectical connection of setup of technical system for seismic monitoring with the scientific research of earthquakes and to better handle the relation between crucial task, current scientif ic level, and the feasibility are the important principles to advance the earthquake science and technology in China. Some success and many setbacks in earthquake disaster mitigation consistently enrich our knowledge regarding the complexity of the conditions for earthquake occurrence and the process of earthquake preparation, promote the reconstruction and modernization of technical system for earthquake monitoring, and deepen the scientific research of earthquakes. During the last 5 years, the improvement and modernization of technical system for earthquake monitoring have clearly provided the technical support to study and practice of earthquake prediction and pre caution, give prominence to key problems and broaden the field of scientific research of earth quakes. These have enabled us to get some new recognition of the conditions for earthquake oc currence and process of earthquake preparation, characteristics of seismic disaster, and mecha nism for earthquake generation in China‘s continent. The progress we have made not only en courages us to enhance the effectiveness of earthquake disaster mitigation, but also provides a basis for accelerating further development of earthquake science and technology in China in the new century, especially in the 10th five-year plan. Based on the history reviewed, the author sets forth a general requirement for develop ment of earthquake science and technology in China and brings out 10 aspects to be stressed and strengthened at present and in the future. These are: upgrade and setup of the network of digitized seismic observation; upgrade and setup of the network for observation of seismic pre cursors; setup of the network for observation of strong motion; setup of the laboratories for ex periment on seismic regime; establishment of technical system for seismic information, emer gency command and urgent rescue; research on short-term and imminent earthquake predic tion; research on intermediate- and long-term earthquake prediction; research on attenuation of seismic ground motion, mechanism for seismic disaster, and control on seismic disaster; ba sic research fields related to seismology and geoscience. We expect that these efforts will signifi cantly elevate the level of earthquake science and technology in China to the advanced interna tional level, improve theories, techniques, and methods for earthquake precaution and predic tion, and enhance the effectiveness of earthquake disaster mitigation.     

Age estimates of coastal terraces in the Andaman and Nicobar Islands and their tectonic implications

The great Indian Ocean earthquake of December 26, 2004 caused significant vertical changes in its rupture zone. About 800 km of the rupture is along the Andaman and Nicobar Islands, which forms the outer arc ridge of the subduction zone. Coseismic deformation along the exposed land could be observed as uplift/subsidence. Here we analyze the morphological features along the coast of the Andaman and Nicobar Islands, in an effort to reconstruct the past tectonics, taking cues from the coseismic effects. We obtained radiocarbon dates from coastal terraces of the island belt and used them to compute uplift rates, which vary from 1.33 mm yr^− 1 in the Little Andaman to 2.80 mm yr^− 1 in South Andaman and 2.45 mm yr^− 1 in the North Andaman. Our radiocarbon dates converge on  600 yr and  1000 yr old coastal uplifts, which we attribute to the level changes due to two major previous subduction earthquakes in the region.     

Nonlinear dynamic finite element simulation of Alibey earth dam

In this study, dynamic behavior and earthquake resistance of Alibey earth dam was investigated. The dam was modeled with four node plane-strain finite elements (FE) and displacement-pore pressure coupled FE analyses were performed. Nonlinear material models such as pressure dependent and independent multi yield materials were implemented during the analyses. Transient dynamic FE analyses were performed with Newmark method. The Newton-Raphson solution scheme was adopted to solve the equations. Liquefaction and/or cyclic mobility effects were considered during the analysis. For the FE analyses, OpenSees (Open System for Earthquake Engineering Simulation) framework was adopted.     

Integration and magnitude homogenization of the Egyptian earthquake catalogue

The aim of the present work is to compile and update a catalogue of the instrumentally recorded earthquakes in Egypt, with uniform and homogeneous source parameters as required for the analysis of seismicity and seismic hazard assessment. This in turn requires a detailed analysis and comparison of the properties of different available sources, including the distribution of events with time, the magnitude completeness, and the scaling relations between different kinds of magnitude reported by different agencies. The observational data cover the time interval 1900–2004 and an area between 22°–33.5° N and 25°–36° E. The linear regressions between various magnitude types have been evaluated for different magnitude ranges. Using the best linear relationship determined for each available pair of magnitudes, as well as those identified between the magnitudes and the seismic moment, we convert the different magnitude types into moment magnitudes M _W, through a multi-step conversion process. Analysis of the catalogue completeness, based on the M _W thus estimated, allows us to identify two different time intervals with homogeneous properties. The first one (1900–1984) appears to be complete for M _W ≥ 4.5, while the second one (1985–2004) can be considered complete for magnitudes M _W ≥ 3.     

中国-俄罗斯原油管道工程(漠河-大庆段)冻土工程地质考察与研究进展

在2005-2007年期间,先后3次对中国-俄罗斯原油管道漠河-大庆段沿线的冻土工程地质条件等进行科学考察,开展了冻土工程地质条件及其在气候变化和人类活动作用下的评价和预测研究.考察研究结果表明:管道沿线多年冻土在各类融区、季节冻土和水系等分隔作用下呈片状或岛状分布,沿线岛状、稀疏岛状及零星岛状占多年冻土区段的40%左右;管道沿线多年冻土随着气候的转暖和人类活动的影响不断退化.地形地貌单元、植被分布、地表水分条件的变化等局部因素对多年冻土的分布和地下冰的赋存产生重要的影响,管道沿线大约分布有50 km左右的沼泽湿地,其表层为腐殖质土及泥炭层,泥炭层下面分布着含土冰层或地下冰,是管道沿线最差的冻土工程地质地段;由于中俄原油管道沿线水系发育多,冻胀丘、冰椎和冰幔等不良冻土现象广泛分布.科学考察的成果为管道沿线冻土工程地质条件评价和预测、管道的稳定性影响分析以及后期的长期检测系统设置等研究奠定坚实的基础,进一步为即将开工的中俄原油管道漠河-大庆段工程的设计、施工提供科学依据.     

PSO-RBFNN模型及其在岩土工程非线性时间序列预测中的应用

岩土工程受力变形演化是一个典型的非线性问题,其演化的高度非线性和复杂性,很难用简单的力学、数学模型描述,但可用粒子群优化径向基神经网络对岩土工程应力、位移非线性时间序列进行动态实时预测。网络径向基层的单元数通过均值聚类法确定后,所有其它参数：中心位置、形状参数、网络权值,均通过粒子群优化算法在全局空间优化确定。工程实例应用表明,该模型预测结果准确、精度高,有良好的应用前景。     

加强技术创新服务地质调查——庆祝探矿工艺研究所成立30周年

为加强地质探矿技术力量,改变地质装备落后现状,经国务院批准,1978年8月8日成立了探矿工艺研究所。30年来,经过新老两代工艺所人的艰苦奋斗、刻苦钻研、勇于创新,在科研攻关、成果转化、基地建设和管理等方面都取得了可喜的成绩,为国家的地质科学事业做出了贡献,目前已成为一个“以勘查技术为基础,以承担地质调查任务和科研项目、提供勘查与监测技术方法和技术服务为手段,以服务国家经济建设、社会发展和地质工作为目标,以探矿工艺技术和地质灾害监测防治技术研发为主业”的地质调查科研机构。回顾了工艺所艰苦创业、改革进取的发展历程,对科技体制改革、专业结构调整、人事分配制度改革、地质调查和科研工作进行了总结,展示了丰硕的科研成果和强劲的科技实力;指出了工艺所在“十一五”期间地质调查和科研工作的重点领域和优先发展方向。     

GYD-300型全液压动力头工程钻机的研制

GYD-300型全液压动力头工程钻机为全液压驱动,动力头反循环式机型。液压系统采用插装阀集成结构,电液复合操作。使用PC控制监测系统,适时检测孔底各相关压力,对不同地层进行范围设置,实现钻进过程中孔底的自动、手动恒压钻进。重点介绍了该钻机的结构特点、实验情况、主要技术参数等。     

土壤渗滤处理技术在海岛生活污水处理中的应用

土壤渗滤处理系统设备简单、投资少、操作管理方便、能耗低,净化效果良好,在处理海岛生活污水领域具有广阔的发展前景.根据鼓浪屿目前污水水质、水量的特点,采用土壤渗滤高度水处理技术对污水进行处理,污染物经过土壤的物理、化学和生物作用,出水达到《城市污水再生利用城市杂用水水质》(GB/T18920-2002),具有不产生污泥,运行简单,氮磷去除效率高,无二次污染等特点.