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1.
P. Marinos G. Bouckovalas G. Tsiambaos N. Sabatakakis A. Antoniou 《Engineering Geology》2001,62(4):343-356
The 1999, Ms=5.9, Athens earthquake caused serious structural damage to buildings in the western part of Athens, Greece. This paper presents the ground zoning against seismic hazard proposed shortly after the earthquake in order to aid reconstruction of the area. Existing engineering geological and geotechnical data were combined with local observations to provide a unified set of classification criteria, consistent with provisions of the Greek Seismic Code EAK. The accuracy and the possible limitations of this zoning procedure are addressed through comparison with observed damage distribution as well as results from seismic ground response analyses performed at sites with well established soil profiles. There is clear evidence that the proposed zones correspond to geological formations exhibiting grossly different seismic response with regard to the design of common engineering structures. However, the mostly qualitative nature of the guidelines for ground categorisation provided by EAK and the general lack of systematic, site-specific geotechnical data for the whole area induce uncertainties in the definition of the seismic design actions for the different zones. These objective uncertainties certainly demand increased conservatism but do not limit application of the proposed methodology for first aid, preliminary planning in the event of destructive earthquakes. 相似文献
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Influence of dune stabilization on relationship between plant diversity and productivity in Horqin Sand Land, Northern China 总被引:1,自引:0,他引:1
Xiaoan Zuo Xueyong Zhao Shaokun Wang Yuqiang Li Jie Lian Xin Zhou 《Environmental Earth Sciences》2012,66(5):1547-1556
The city of Split has been developing continuously since the construction of the Diocletian Palace (287–305) to the present time. Detailed engineering geological investigations, with the recorded documents, have been performed since 1970. Further development and expansion of the city require an urban engineering geological map to be developed as a main prerequisite for the geotechnical and seismic zonation. In this paper a review of engineering geological conditions at the area of Split City (cca 25 km2) is given. Those conditions are interpreted on the basis of available data from geotechnical reports (about stratigraphical units, their lithological composition and physical and mechanical properties) and limited field survey. Zones with different ground conditions regarding rock properties are delineated in the form of lithological complex, engineering geological mapping units for medium-scale maps. The area of the city of Split, built of foraminifera limestones (E1,2), clayey glauconitic limestones (E21,2 E_{2}^{1,2} ), and flysch sediments (E2,3), is divided into five lithological complexes, which presents unique combination of individual lithological type for which it is possible to indicate general behavior of the whole. The paper also provides short review of other environmental conditions (active geomorphological processes, hydrological and hydrogeological conditions, as well as seismic conditions), which are intended as a guide to the sort of environmental data that could be collected by more detailed studies during the course of the zoning process. 相似文献
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V. Marinos G. Prountzopoulos P. Fortsakis D. Koumoutsakos K. Korkaris D. Papouli 《Geotechnical and Geological Engineering》2013,31(3):891-910
Existing experience from the design and construction of underground works is of major importance for the improvement of the construction methods and procedures in tunnelling, especially under adverse and complex geological and geotechnical conditions. This experience can be of great value to geotechnical engineers and engineering geologists, if data acquired through the ground investigation, the design and the construction is systematically collected, categorized and stored in a properly structured database that enables a targeted access to it, as well as to proceed to correlations and analysis, based on engineering criteria. Such a database should be carefully designed to “connect” all available data through all the phases of a tunnel project and premises deep knowledge from the geological and geotechnical investigation to the final design and construction. In order to make substantial use of the experience accumulated from the construction of a great number of tunnels, a database named Tunnel Information and Analysis System (TIAS) was developed. The data source for TIAS database was 62 tunnels of the Egnatia Highway in northern Greece, many of which have been constructed under difficult geological conditions in weak rock masses. The data processed by TIAS came from a variety of sources such as geological mapping, boreholes, laboratory and in situ testing, geotechnical classifications, engineering geological behaviour, groundwater, design parameters, information concerning immediate support measures, construction records and cost. The purpose of the system, besides incorporating extended and multi-source data for easy access, is to provide a tool for turning data into usable information for the comparison of anticipated and encountered geological and geotechnical conditions, the evaluation of geotechnical classification and design methods and the relations regarding rock mass conditions and behaviour and immediate support methods and types. 相似文献
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Engineering geophysics provides valuable and continuous information for the planning and execution of tunnel construction
projects. For geotechnical purposes special high-resolution geophysical methods have been developed during the last decades.
The importance of applying geophysical methods in addition to usually used geological and geotechnical exploration techniques
is increasing. The main goal is to achieve an accurate and continuous model of the subsurface in a relative short period of
operation time. The routine application of engineering geophysical methods will increase in the coming years. Due to the high
acceptance of engineering geophysics at construction sites, much wider application of geophysical investigations is expected.
The combination of different methods—geophysics, geology, and geotechnics as well as the so-called joint interpretation techniques—will
be of essential importance. Engineering geophysics will play an important role during the three phases: geological investigation,
tunnel planning, and execution of tunnel construction. If hazards are well known in advance of a tunnel project the safety
of workers will essentially be increased and geological risks will be minimized by means of successful and interdisciplinary
cooperation. 相似文献
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根据峰峰矿区工业及民用建筑的岩土工程特征,以及在岩土工程勘察中所遇到的诸如由地形地貌产生的不良工程地质现象、特殊地质体等问题,认为在岩土工程勘察中,不仅要研究勘察场地的工程地质条件,而且要重视周围地质条件的宏观研究,同时建议建立岩土工程勘察档案数据库,为今后岩土工程勘察成果的使用、以及正确确定勘察手段奠定基础。 相似文献
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NIELS FOGED 《Boreas: An International Journal of Quaternary Research》1987,16(4):419-424
Engineering geology, like geotechnical engineering, is a new scientific subject in Denmark. Experience in the period since 1924 is laid down in the Danish Code of Practice for Foundation Engineering, which states that the geological conditions establish the foundation class and must be determined as early as possible during the soil investigations by experienced geologists and engineers. The consequences are illustrated by some examples from geotechnical investigations performed at the Danish Geotechnical Institute:
• The economic foundation of a small wooden building on the brink of a postglacial lake and fiord basin at Vedbæk.
• The deep excavation for and foundation of a huge commercial center at Lyngby situated in the middle of a tunnel valley with more than 12 m late- and postglacial organic deposits, based on design and control in the high foundation class.
• The engineering geological modelling of the Quaternary development in the Danish North Sea. Applied geology plays an increasing part in geotechnical engineering as a prerequisite for economic and safe technical solutions. The future use of geological and geotechnical data bases will bring Quaternary geological knowledge into focus. 相似文献
• The economic foundation of a small wooden building on the brink of a postglacial lake and fiord basin at Vedbæk.
• The deep excavation for and foundation of a huge commercial center at Lyngby situated in the middle of a tunnel valley with more than 12 m late- and postglacial organic deposits, based on design and control in the high foundation class.
• The engineering geological modelling of the Quaternary development in the Danish North Sea. Applied geology plays an increasing part in geotechnical engineering as a prerequisite for economic and safe technical solutions. The future use of geological and geotechnical data bases will bring Quaternary geological knowledge into focus. 相似文献
8.
Application of EM algorithms for seismic facices classification 总被引:1,自引:0,他引:1
Identification of the geological facies and their distribution from seismic and other available geological information is
important during the early stage of reservoir development (e.g. decision on initial well locations). Traditionally, this is
done by manually inspecting the signatures of the seismic attribute maps, which is very time-consuming. This paper proposes
an application of the Expectation-Maximization (EM) algorithm to automatically identify geological facies from seismic data.
While the properties within a certain geological facies are relatively homogeneous, the properties between geological facies
can be rather different. Assuming that noisy seismic data of a geological facies, which reflect rock properties, can be approximated
with a Gaussian distribution, the seismic data of a reservoir composed of several geological facies are samples from a Gaussian
mixture model. The mean of each Gaussian model represents the average value of the seismic data within each facies while the
variance gives the variation of the seismic data within a facies. The proportions in the Gaussian mixture model represent
the relative volumes of different facies in the reservoir. In this setting, the facies classification problem becomes a problem
of estimating the parameters defining the Gaussian mixture model. The EM algorithm has long been used to estimate Gaussian
mixture model parameters. As the standard EM algorithm does not consider spatial relationship among data, it can generate
spatially scattered seismic facies which is physically unrealistic. We improve the standard EM algorithm by adding a spatial
constraint to enhance spatial continuity of the estimated geological facies. By applying the EM algorithms to acoustic impedance
and Poisson’s ratio data for two synthetic examples, we are able to identify the facies distribution. 相似文献
9.
Shear wave velocity is one of the most important input parameter in the analysis of geotechnical earthquake engineering problems,
particularly to estimate site-specific amplification factor and ground response study. Dynamic in situ tests such as spectral
analysis of surface waves (SASW) or multichannel analysis of surface waves (MASW) are very expensive. Also due to lack of
specialized personnel, these tests are generally avoided in many soil investigation programs. Worldwide, several researchers
have developed correlations between the SPT ‘N’ value and shear wave velocity ‘V
s’, which are useful for determining the dynamic soil properties. In the present study, more than 400 numbers of soil borehole
data were collected from various geotechnical investigation agencies, government engineering institutes and geotechnical laboratories
from different parts of Mumbai city, which is financial capital of India with highest population density. In this paper, an
attempt has been made to develop the correlation between the SPT ‘N’ value and shear wave velocity ‘V
s’ for various soil profile of Mumbai city and compared with other existing correlations for different cities in India. Using
Geographical Information System (GIS), a geospatial contour map of shear wave velocity profile for Mumbai city is prepared
with contour intervals of 25 and 50 m/s. The scarcity of database or maps of shear wave velocity profile for Mumbai city will
make the present geospatial contour maps extremely useful and beneficial to the designer, practitioners for seismic hazard
study involved in geotechnical earthquake engineering. 相似文献
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交通岩土工程信息系统在国民经济和交通工程建设中发挥着重要作用.利用地理信息系统(GIS)技术和计算机技术构建交通岩土工程信息系统是近年来国内交通领域内的研究热点和前沿之一.江西省交通岩土工程信息系统采用组件式地理信息系统(GIS)和计算机技术,并从系统的软硬件设计、系统总体结构设计、系统的功能设计等方面.探讨了江西省交... 相似文献
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岩土工程信息化迫切需要加强大数据集成共享和多专业协同合作,BIM技术在工程建设领域的成功经验给我们以启示,可将BIM技术应用于岩土工程信息化建设,但是当前存在的主要问题是地质模型与BIM模型数据标准不统一。为了解决这个问题,提出了地质模型采用BIM数据标准IFC的思路。采用IFC实体扩展及属性集扩展模式,建立了面向三维地质模型的扩展模型IFC-3DGeoMdl。利用已有的IFC对象类型,派生相应的地质物理实体以及地质空间结构实体,给出地质物理实体的空间表达形式;利用IFC中已有的关系类,定义地质物理实体与空间结构实体的关系;进而,基于IFC中的属性表达方式,实现了地质对象的地层信息与物理力学参数等属性的扩展;最后,给出了创建该模型的具体实现过程,并利用实例验证了该模型的实际应用效果。结果表明,采用该模型,可有效实现岩土工程地质模型与BIM结构模型的集成,从而为深化岩土工程的结构设计、施工等提供有效的地质模型信息。 相似文献
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城市化的发展,使市政道路改造工程越来越多,如何科学有效地利用拟建期的勘察资料,节约勘察成本,成为工程勘察关注的焦点。通过对场地地形地貌和地质构造、地层和水文地质条件、岩土物理力学性质、场地稳定性评价和地震效应、岩土工程重点分析评价等岩土工程要素进行分析,对比前后各要素,探讨勘察资料的时效性,进而确定勘察点布置和深度,以及取土(水)样和原位测试工作量。最后以具体工程为例,探讨勘察要点,指出利用拟建期的勘察资料应主要考虑4.0m以内的地层变化,重点勘察路基破损的路段。 相似文献
13.
Seismic risk assessment of buildings in urban areas: a case study for Denizli,Turkey 总被引:3,自引:2,他引:1
This study aims to carry out a seismic risk assessment for a typical mid-size city based on building inventory from a field
study. Contributions were made to existing loss estimation methods for buildings. In particular, a procedure was introduced
to estimate the seismic quality of buildings using a scoring scheme for the effective parameters in seismic behavior. Denizli,
a typical mid-size city in Turkey, was used as a case study. The building inventory was conducted by trained observers in
a selected region of Denizli that had the potential to be damaged from expected future earthquakes according to geological
and geotechnical studies. Parameters that are known to have some effect on the seismic performance of the buildings during
past earthquakes were collected during the inventory studies. The inventory includes data of about 3,466 buildings on 4,226
parcels. The evaluation of inventory data provided information about the distribution of building stock according to structural
system, construction year, and vertical and plan irregularities. The inventory data and the proposed procedure were used to
assess the building damage, and to determine casualty and shelter needs during the M6.3 and 7.0 scenario earthquakes, representing
the most probable and maximum earthquakes in Denizli, respectively. The damage assessment and loss studies showed that significant
casualties and economic losses can be expected in future earthquakes. Seismic risk assessment of reinforced concrete buildings
also revealed the priorities among building groups. The vulnerability in decreasing order is: (1) buildings with 6 or more
stories, (2) pre-1975 constructed buildings, and (3) buildings with 3–5 stories. The future studies for evaluating and reducing
seismic risk for buildings should follow this priority order. All data of inventory, damage, and loss estimates were assembled
in a Geographical Information System (GIS) database. 相似文献
14.
The article presents a statistical approach to characterize and predict engineering geological conditions in the up to 2000 m deep Faido tunnel and Gotthard base tunnel in Switzerland. Seismic investigations were conducted to improve the technology of interpreting seismic tomographic images. Overall, the goal of this study was to predict spacial maps of geological rock mass properties, such as, uniaxial compressive strength or total fracture spacing, by using up to six seismic features in combination, e.g., compression-wave and shear-wave velocities and dynamic Poisson's ratio. Self-Organizing Mapping (SOM), an artificial intelligent method, was used for the purposes of interpreting multi-dimensional geophysical attributes derived from seismic profiles of tomographic images along tunnel sidewalls. The SOM-method was applied in the Faido tunnel to delineate complex physical relations between the geological and seismic parameters. Then, the method was applied to predict geological properties around a segment of the Gotthard base tunnel with unknown geological–geotechnical conditions. The results illuminate that correlation analyses (pairwise parameter classification) are substantially less powerful than the SOM-method (multi-parameter classification) in order to interpret geological features from seismic in-situ data. Moreover, predicted spatial distributions of the total fracture spacing and the uniaxial compressive strength, for example, corresponded well with drill core and tunnel mapping results. The SOM-approach was a helpful tool for practitioners in predicting zones of instabilities and geological complexity during underground excavation processes of the Gotthard base tunnel. It is suggested to use such an interpretation method as decision support for purposes of sub/surface exploration and long-term geophysical monitoring of large-scale geoengineering projects, such as, disposals of nuclear waste and greenhouse gases or geopower plants for renewable energy (geothermal, biosoils). 相似文献
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基于ArcGIS信息集成平台和Oracle数据库,构建了常州市工程地质数据库智能系统框架,对长期分散积累的工程地质数据进行收集整理、挖掘利用,开发了工程地质数据科学管理和辅助决策功能,集工程地质数据管理与发布、工程地质数据处理、工程地质数据分析、地下空间规划分析、地下工程可视化与分析子系统于一体,可为城市规划、城市建设和决策,提供工程地质依据。 相似文献
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M. Hashemi M. R. Nikoudel N. Hafezi Moghaddas M. Khamehchiyan 《Arabian Journal of Geosciences》2014,7(6):2339-2352
A broad assessment of the geological, sedimentological, and geotechnical characteristics of the coastal Holocene sediments of Anzali Area (North Iran) was made to provide a useful guide for development, planning, and construction. Based on the sedimentological and geotechnical properties of the sediments, three engineering geological units as Upper Sandy Zone (USZ), Middle Clayey Zone (MCZ), and Lower Sandy Zone (LSZ) were identified and introduced in the form of an engineering geological model. Then the engineering geological characteristics of the units of the model were analyzed and the main engineering geological problems associated with the deposits of each unit were identified. The results showed that USZ has high liquefaction potential, low bearing capacity, settlement susceptibility, and excavation problem; MCZ has low-bearing capacity as well as high settlement susceptibility and excavation problem; and LSZ has good geotechnical properties, then it poses few problems. 相似文献
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Francesca de Rienzo Pierpaolo Oreste Sebastiano Pelizza 《Geotechnical and Geological Engineering》2009,27(4):539-547
This paper introduces a 3D geological and geotechnical model of the subsoil of the city of Turin managed by means of a Geographical
Information System (GIS). The 3D GIS of the subsoil of Turin represents a useful decision-support tool in the underground
management for engineering purposes and it’s here proposed as base geological elaborate to support future underground work
in the city. In the final part of the paper, an application of the information coming from the 3D model is shown to define
the characteristics of the optimal excavation machines (the type and disposition of tools on the head and the necessary engine
power) for the future developments of the Underground Metro System. 相似文献