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731.
腾冲科学钻探孔非弹性应变恢复法三维地应力测量   总被引:1,自引:0,他引:1  
用非弹性应变恢复法(简称ASR法)进行了腾冲科学钻探孔地应力测量。基于岩芯测量的ASR法是近年来发展起来的深部三维地应力测量的一种经济实用的新方法。使用该方法进行了720 m至1098 m深处的三维地应力测量,获得了该深度范围的地应力状态。测量结果表明:最大和中间主应力近于水平,最小主应力近于铅直。最大水平主应力方向为30°到45°。测量结果与地震机制解进行了对比。对比表明,ASR法得到的结果与地震机制解非常吻合。应力状态有利于高角度断层产生走滑运动,低角度断层产生逆冲运动。这与腾冲地区的地震断层活动性质一致。测量结果对地震机理的研究有意义。  相似文献   
732.
Usual ductile shear zone has relatively high strain magnitude.However,for high-grade metamorphic rocks in Daqingshan area,the related strain is very low with weakly developed lineation.Significantly,the fi-nite strain type with a K-value slightly lower than 1 and is characterized by compressional strain.Because the special tectonic environment with high temperature,the percentage of melt is relatively higher,which leads to a series of microscopic phenomenon such as multi-grain quartz bands,feldspar three edges equilibrium-like tex-ture,granular flow,etc.As a consequence,the tectonites in the studied area illustrate a unique character:ob-vious rheological meso-deformation structure but with very weak intracrystalline micro-deformation.  相似文献   
733.
本文简要介绍了地下管网三维可视化的必要性,并通过镇江新区(大港)地下管线的三维建模,简述了三维仿真管线系统在城市规划建设管理中的应用。  相似文献   
734.
针对在智慧管网环境下,大量多元化智能终端设备或传感设备接入前置机时,如何统一入口进行海量数据的高效能通信,提出了一种可行的解决方案。依据该方案开发的智慧管网通信前置系统,可以实现多台前置机高效协同通信与负载均衡,能实时获取海量的城市管线设施传感数据,是一种通信能力可扩展的高性能通信前置系统。  相似文献   
735.
王运安 《海岸工程》2003,22(3):38-45
针对胜利石油管理局“滩海铺管敷缆船”总体设计情况,分别从设计指标、基本功能、主要性能参数、关键技术和总体布置等几个方面进行了较详细的介绍。该装备具有性能指标先进、设备装备精良、工艺流程合理、安全可靠和注重环保的特点,适用于我国浅海油田及其它相同情况海域。  相似文献   
736.
The wave force on a seawater intake structure consisting of a perforated square caisson of 400 mm×400 mm size encircling a vertical suction pipe of 160-mm diameter is investigated using physical model studies. The porosity of caisson was varied from 1.6 to 16.9%. Regular and random waves of wide range of heights and periods were used. It is found that the force ratio (ratio of the force on perforated caisson to the force on caisson with zero percent porosity) reduces to an extent of up to 60% with increase in porosity of the caisson from 1.6 to 16.9%. The force ratio was found to increase with increase in relative wave height and reduces with increase in relative width. Multiple regression analysis of the measured data points was carried out and predictive equations for wave force ratios are obtained both for regular and random waves. The results of this investigation can be used in the hydrodynamic design of perforated caissons, which are widely used as seawater intake structures.  相似文献   
737.
YANG  He-zhen 《中国海洋工程》2003,17(4):495-504
In this paper Nondestructive Damage Detection (NDD) for offshore platforms is investigated under operational conditions. As is known, there is no easy way to measure ambient excitation, so damage detection methods based on ambient excitation have become very vital for the Structural Health Monitoring (SHM) of offshore platforms. The modal parameters (natural frequencies, damping ratios and mode shapes) are identified from structural response data with the Natural Excitation Technique (NExT) in conjunction with the Eigensystem Realization Algorithm (ERA) . A new method of damage detection is presented, which utilizes the invariance property of element modal strain energy. This method is to assign element modal strain energy to two parts, and defines two damage detection indicators. One is compression modal strain energy change ratio (CMSECR); the other is flexural modal strain energy change ratio (FMSECR). The present modal strain energy is obtained by incomplete modal shape and structural stiffness matr  相似文献   
738.
A kind of diatomaceous soft rock and its constitutive model are studied in this article. Based on Yin and Graham's (1999) 3-D elastic viscoplastic constitutive model, the formulation under a triaxial stress state is established, and it is used to simulate the time-dependent stress-strain behavior and effective stress path of consolidated undrained triaxial tests of both normally consolidated and overconsolidated soft rock. The comparison between the model predictions and measured results shows that their agreement is good. This demonstrates that the constitutive equation established here can be used to simulate the time-dependent stress-strain behavior of the soft rock under triaxial stress condition.  相似文献   
739.
740.
1 .IntroductionSubmarine pipelines have been worldwide utilizedinthe field of offshore oil/gas exploitation.Inmany cases ,the pipelinesinitiallyresting onthe seabed may become suspended due toseveral reasonssuch as installation on an uneven seabed or scou…  相似文献   
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