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91.
管线探测与管线(网)信息系统相结合提高市场竞争力 总被引:1,自引:0,他引:1
姜作勤 《物探化探计算技术》1997,19(4):351-356
涉及上水、雨水、污水、热力、煤气、电力、电讯和工业管道的管线(网)是城市和企业的重要基础设施。有关信息是否完整、准确,对这些信息的管理是否有效直接影响着城市规划,管理的科学笥,合理性,影响城市建设的效率及安全,影响人民生活的正常秩序。随着我国经济建设的加快,城市规模的扩大,在管线探测与管网信息系统的建设方面形成了较大的市场潜力,本文分析了市场需求,发展现状和我部开拓相应市场的力量和技术优势,提出管 相似文献
92.
Empirical scaling equations are presented which relate the average number of water pipe breaks per km2,
, with the peak strain in the soil or intensity of shaking at the site. These equations are based on contour maps of peak surface strain evaluated from strong motion recordings, and observations of intensity of ground shaking and damage following the Northridge, California, earthquake of 17 January 1994. Histograms for the number of pipe breaks per km2, n, are presented for several ranges of values of the horizontal peak strain and for several values of the site intensity. The observed distribution of pipe breaks is also used to speculate on possible more detailed geographical distribution of near surface strains in the San Fernando Valley and in central Los Angeles. The results can be used to predict number of pipe breaks in the San Fernando Valley and in Los Angeles, for a scenario earthquake or in probabilistic seismic hazard calculations, considering all possible scenarios that contribute to the hazard and the likelihood of their occurrence during specified exposure. Such predictions will be useful for emergency response planning (as the functioning of the water supply is critical for sanitation and in fighting fires caused by earthquakes), to estimate strains during future and past earthquakes in areas where no strong motion was recorded and in defining design guidelines for pipelines and other structures and structural systems sensitive to strains in the ground. 相似文献
93.
94.
吕悦 《测绘与空间地理信息》2017,(8)
城市地下管线是城市的"生命线",管线探测的质量控制受到业内专家和作业单位的广泛关注。本文总结了地下管线探测工程质量控制方法,强调了过程质量控制的重要性,可为其他单位城市地下管线探测工程项目提供借鉴和参考。 相似文献
95.
96.
- With the rapid development of the offshore oil industries, submarine oil / gas pipelines have been widely used. Under the complicated submarine environmental conditions, the dynamic characteristics of pipelines show some new features due to the existence of both internal and external flows. The paper is intended to investigate the vortex-induced vibration of the suspended pipeline span exposed to submarine steady flow. Especially, the effects of the flow inside the pipeline are taken into account. Its influences on the amplitude of pipeline response, and then on the fatigue life, are given in terms of the velocity of the internal flow. 相似文献
97.
海底路由勘察综合图是海底电缆管道路由区的海底地形地貌、海底面状况和工程地质条件勘察成果的综合反映,是路由设计施工的重要依据。目前综合图的绘制需要大量人工编辑,缺乏批量生产能力,本文研究了路由勘察数据特征,利用AutoCAD VBA开发技术实现了水深数据分级分色展绘、地形剖面成图、浅地层剖面解译数据剖面投影以及成果图框的自动化生成,应用证明该技术对降低作业难度、提高内业处理效率具有较高的实用价值。 相似文献
98.
A semi-analytical method of the stress-strain analysis of buried steel pipelines under submarine landslides was proposed, considering the nonlinearities of the pipe-soil interaction and mechanical properties of the pipe steel. The pipeline was divided into three parts according to different loading conditions, and the corresponding differential equations were established based on a combination of the beam-on-elastic foundation and elastoplastic-beam theories. According to the second-order central difference method, the transverse horizontal displacement was calculated, and then the bending strain was obtained based on the relation between bending strains and curvatures. Considering the interaction between the axial and bending strains, the axial strain can be derived from the equilibrium condition by equating the axial force. The proposed method was verified through the comparison of obtained solutions to ANSYS results, with minor deviations which do not exceed about 4.6%. Additionally, the effects of the slide width, the buried depth of pipelines, the internal friction angle of soils, the cohesion of soils and the bulk density of soils are investigated through parametric studies. 相似文献
99.
100.
Lateral buckling is an important issue in unburied high-temperature and high-pressure (HT/HP) subsea pipelines systems. The imperfection–sleeper method is one of the most well-known methods used to control lateral buckling of HT/HP pipelines. Pipelines–sleeper–seabed numerical models are established and verified to analyze the buckling behavior of pipelines using the imperfection–sleeper method. The influence of six main factors on lateral buckling behavior is investigated in details based on the numerical results. Equations of buckling displacement (buckling displacement is defined by the final displacement of the middle point of the pipelines), critical buckling force, and buckling stress (Mises stress) are proposed using the gene expression programming technique. These equations show good accuracy and can be used to assist in the design of sleepers and assess the compressive and stress levels of pipelines. 相似文献