复杂地基条件下土-结构动力相互作用分析

结构和地基动力相互作用(SSI)分析对大坝、桥梁、核电、地下结构的抗震安全评价具有重要意义。本文对SSI分析的发展现状和工程设计实践进行了扼要评述。值得指出,2011年日本福岛核电事故后,国际上普遍提高了对核电结构抗震安全性的需求。因此,对重要结构的安全评价发展更为完善的先进SSI计算模型势在必行。为此目的,对处于复杂地基条件下的SSI分析提出一种新的计算模型,可以方便地考虑结构近场各种非均质因素的影响而不增加计算工作量,其中包括地基分层、基础埋深、建基面水平、存在相邻建筑物、附近出现软弱地质体等因素。这使SSI的计算更为准确和高效。论文的数值算例论证了所建议方法的有效性。

地质灾害易发山区新农村房屋建设选址理论与方法

过去农村房屋建设,大多未进行科学选址,随意烂挖乱建,致使不少房屋建在陡坡、陡崖脚、滑坡、崩塌、泥石流等地质灾害易发区内,存在严重的灾害隐患。新农村建设应彻底转变过去落后的建房方式,建房前应进行科学的选址。对拟建房区域的自然地质环境、地质灾害现状进行详细调查、评估,进行灾害危险性分区、建房地基环境分类。把新建房屋选在Ⅰ类地基环境区,若Ⅰ类区较少;满足不了新建房屋需要,可选少量条件较好的Ⅱ类地基环境区,但需加强对环境的保护,开挖边坡应及时加固,对可能引发、遭受的地质灾害进行治理。

Question and Countermeasure Research of Human Living Environment Designs in New Countries

In the view of new rural living environment,problems existing in the construction of current new rural living environment were analyzed so as to propose some theoretical ideas and ways for resolving the problems existing in the design of new rural living environment.

Environmental effects induced by excavation

Based on 3D Biot’s consolidation theory and nonlinear Duncan-Chang’s model, a 3D FEM (finite element method) program is developed considering the coupling of groundwater seepage and soil skeleton deformation during excavation. The comparison between the analysis result considering the variation of water head difference and that without considering it shows that the porewater pressure distribution of the former is distinctly different from that of the latter and that the foundation pit de- formations of the former are larger than those of the latter, so that the result without considering the variation of water head dif- ference is unreliable. The distribution rules of soil horizontal and vertical displacements around the pit and excess porewater pressure are analyzed in detail in time and space, which is very significant for guiding underground engineering construction and ensuring environment safety around the pit.

Identification of Light-Harvesting Chlorophyll a/b-Binding Protein Genes of Zostera marina L.and Their Expression Under Different Environmental Conditions

Photosynthesis includes the collection of light and a/b-binding （LHC） proteins. In high plants, the LHC gene family constituting the light-harvesting complex ofphotosystems I and II. the transfer of solar energy using light-harvesting chlorophyll includes LHCA and LHCB sub-families, which encode proteins Zostera marina L. is a monocotyledonous angiosperm and inhab- its submerged marine environments rather than land environments. We characterized the Lhca and Lhcb gene families of Z. marina from the expressed sequence tags （EST） database. In total, 13 unigenes were annotated as ZmLhc, 6 in Lhca family and 7 in ZmLhcb family. ZmLHCA and ZmLHCB contained the conservative LHC motifs and amino acid residues binding chlorophyll. The average similarity among mature ZmLHCA and ZmLHCB was 48.91% and 48.66%, respectively, which indicated a high degree of diver- gence within ZmLHChc gene family. The reconstructed phylogenetic tree showed that the tree topology and phylogenetic relation- ship were similar to those reported in other high plants, suggesting that the Lhc genes were highly conservative and the classification of ZmLhc genes was consistent with the evolutionary position of Z. marina. Real-time reverse transcription （RT） PCR analysis showed that different members of ZmLhca and ZmLhcb responded to a stress in different expression patterns. Salinity, temperature, light intensity and light quality may affect the expression of most ZmLhca and ZmLhcb genes. Inorganic carbon concentration and acidity had no obvious effect on ZmLhca and ZmLhcb gene expression, except for ZmLhca6.

Research on infiltration clogging effect and its application prospect in anti-seepage project

Clogging effect,as a new concept in geological engineering,is a phenomenon of permeability decreasing under seeping in reservoir dam foundation of the alluvial and diluvial deposits with deep and thick layer,coarse particle and high permeability in mountains-gully rivers of Tibetan Plateau.A clogging infiltration instrument has been designed successfully and a series of simulation tests have been done.Based on large amounts of data,it is confirmed that the existence of the clogging effect and the law of infiltration clogging is found out.Three indexes are proposed such as "optimal size of particle","optimal size range of particle" and "characteristic pore",which are closely related with effect of infiltration clogging.The concept and results can offer a new idea to solve problems on anti-seepage of dam foundation in mountains-gully rivers environment and to study artificial clogging,meanwhile supplement of the concept of seepage deformation.

Geospatial susceptibility mapping of earthquake-induced landslides in Nuweiba area, Gulf of Aqaba, Egypt

Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the earthquake-induced landslide susceptibility in Nuweiba area in Egypt with considerations of geological, geomorphological, topographical, and seismological factors. An integrated approach of remote sensing and GIS technologies were applied for that target. Several data sources including Terra SAR-X and SPOT 5 satellite imagery, topographic maps, field data, and other geospatial resources were used to model landslide susceptibility. These data were used specifically to produce important thematic layers contributing to landslide occurrences in the region. A rating scheme was developed to assign ranks for the thematic layers and weights for their classes based on their contribution in landslide susceptibility. The ranks and weights were defined based on the knowledge from field survey and authors experiences related to the study area. The landslide susceptibility map delineates the hazard zones to three relative classes of susceptibility: high, moderate, and low. Therefore, the current approach provides a way to assess landslide hazards and serves for geo-hazard planning and prediction in Nuweiba area.

Load Sharing Performance of the Main Drive System in the Shield Machine and Improvement of Control Method

Shield machine is the major technical equipment badly in need in national infrastructure construction. The service conditions of shield machine are extremely complex. The driving interface load fluctuation caused by geological environment changes and multi field coupling of stress field may lead into imbalance of redundant drive motors output torque in main driving system. Therefore, the shield machine driving synchronous control is one of the key technologies of shield machine. This paper is in view of the shield machine main driving synchronous control, achieving the system＇s adaptive load sharing. From the point of view of cutterhead load changes, nonlinear factors of mechanical transmission mechanism and the control system synchronization performance, the authors analyze the load sharing performance of shield machine main drive system in the event of load mutation. The paper proposes a data-driven synchronized control method applicable to the main drive system. The effectiveness of the method is verified through simulation and experimental methods. The new method can make the system synchronization error greatly reduced, thus it can effectively adapt to load mutation, and reduce shaft broken accident.

Geomorphosites in Granitic Environments： An Example from Northern Sardinia （Italy）

A rare geomorphosite and a pillow-like structure appearing as mingling structures due to that mafic and acidic magma interactions are described. Despite the occurrence of spectacular forms in the granitic basement of Sardinia, the morphosites of geological interest linked to the complex evolution of pluton emplacement are still poorly understood. The Fizza Ona outcrop, located near the northeastern coast, is a good example of a geomorphosite in the inner zone developed at the edge of different plutonic units. This outcrop is a well-exposed, pillow-like horizon of less than 5 m in thickness, observable in the field for at least 200 m and underlined by the occurrence of a large tafoni form. In detail, the pillow-like horizon consists of sub-roundly to sub-rounded elements of granitic to micropegmatitic rocks of up to 100 cm in diameter, which is dispersed in the fine-grained granitic host-rock matrix. The outcrop represents a particular example of the emplacement mechanism of granitic magmas in the Sardinian batholith. One aim of this work is the construction of a document for the competent authorities to protection and preservation of this outcrop as a cultural heritage for the history of the geological evolution.

Regional Economic Development in China——Situation,Problems and Policy Recommendations

The growth of regional economy in China was stable with a slight decline in2013.Growths in major economic indicators,namely the industrial added value,the total fixed asset investment,the total retail sales of consumer goods,and the total volume of import and export trade differ across the eastern,central,western and northeastern regions,but the overall difference is small.The regional economic development still faces certain problems,such as unbalanced development among regions,insufficient implementation of development planning,lack of in-depth regional cooperation,irrational competition of development of new zones,and uncoordinated policies on ecological progress from different government authorities.This paper suggests that China should formulate zoning policies and supporting measures to accelerate the development of key economic belts,promote new urbanization,transform the old industrial bases,strengthen joint prevention of regional environmental pollution and promote the opening up of the inland areas to the western regions.

Limits to Resources,Economic Growth and Happiness

Terrible scenario for the future aspect of our society was issued by ＂The Limits to Growth＂. Basic problems that we confront are the restricted natural resources and the environment. Regarding the resources, the overall average of the reserve/production ratio is predicted to fall below 10 years by 2040. Aggressive developments of mines based on the sense of urgency for metal resources cause strong conftiction with the environment and the people living there. Resultantly, urban mine becomes more realistic than before. From the view point of ecological foot print, 5.3 globes are needed if all the people living in the world attain the affluent life same as USA. On the other hand, it is clear that we can get larger utility by smaller goods if our scale of satisfaction is reduced. We have to notice that happiness is our ultimate purpose, economy and industry are intermediate, and natural resources support the all from the basis.

Genomics,metagenomics,and microbial oceanography—A sea of opportunities

Microbial oceanography is an emerging discipline resulted from the interaction,cross-fertilization and integration of life science and ocean science.Microbial oceanography integrates the principles of marine microbiology,microbial ecology and oceanography to study the role of microorganisms in the biogeochemical dynamics of natural marine ecosystems.The application of genomics tools to study marine microbes is resulting in rapid advancements in microbial oceanography that has important implications in global carbon cycle,climate change,and ecosystem function.Here we review the application of genomics and metagenomics in microbial oceanography and suggest future directions in microbial oceanography research.