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1.
Vertical drains are usually installed in subsoil consisting of several layers. Due to the complex nature of the problem, over the past decades, the consolidation properties of multi‐layered ground with vertical drains have been analysed mainly by numerical methods. An analytical solution for consolidation of double‐layered ground with vertical drains under quasi‐equal strain condition is presented in this paper. The main steps for the computation procedure are listed. The convergence of the series solution is discussed. The comparisons between the results obtained by the present analytical method and the existing numerical solutions are described by figures. The orthogonal relation for the system of double‐layered ground with vertical drains is proven. Finally, some consolidation properties of double‐layered ground with vertical drains are analysed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
2.
Approach to Mountain Hazards in Tibet, China 总被引:1,自引:1,他引:0
MADongtao TUJianjun CUIPeng LURuren 《山地科学学报》2004,1(2):143-154
Tibet is located at the southwest boundary of China. It is the main body of the Qinghai-Tibet Plateau, the highest and the youngest plateau in the world. Owing to complicated geology, Neo-tectonic movements, geomorphology, climate and plateau environment, various mountain hazards, such as debris flow, flash flood, landslide, collapse, snow avalanche and snow drifts, are widely distributed along the Jinsha River (the upper reaches of the Yangtze River), the Nu River and the Lancang River in the east, and the Yarlungzangbo River, the Pumqu River and the Poiqu River in the south and southeast of Tibet. The distribution area of mountain hazards in Tibet is about 589,000 km^2, 49.3% of its total territory. In comparison to other mountain regions in China, mountain hazards in Tibet break out unexpectedly with tremendously large scale and endanger the traffic lines, cities and towns, farmland, grassland, mountain environment, and make more dangers to the neighboring countries, such as Nepal, India, Myanmar and Bhutan. To mitigate mountain hazards, some suggestions are proposed in this paper, such as strengthening scientific research, enhancing joint studies, hazards mitigation planning, hazards warning and forecasting, controlling the most disastrous hazards and forbidding unreasonable human exploring activities in mountain areas. 相似文献
3.
地勘单位在向企业化经营转变的过程中 ,投资兴办了许多企业 ,但不少项目以失败告终。文章分析探讨了失败的原因 ,并提出相应的对策 相似文献
4.
Effect of Inter-Column Spacing on Soil Stresses due to Vibro-Installed Stone Columns: Interesting Findings 总被引:1,自引:0,他引:1
Hesham Elshazly Mohamed Elkasabgy Azza Elleboudy 《Geotechnical and Geological Engineering》2008,26(2):225-236
This paper reveals the interesting relation between the inter-column spacing and the corresponding alteration of soil state
of stresses due to the vibro-installation technique. This relation is inferred from analyses for load settlement records of
various field load tests, performed for stone columns arrangements with different inter-column spacing values. In order to
have adequate confidence in the findings, a well-documented case history, involving three columns patterns along with their
relevant field and laboratory test results, is utilized for this study. Moreover, a well-tested finite element model, capable
of simulating both elasto-plastic and time dependent soil deformations as well as pore water pressure building and dissipation,
is employed in the analysis. Instead of determining the soil response to the test load, based on known initial soil stresses
and material properties, the analysis is inversely posed to determine the soil initial stresses, based on the recorded settlements
and the post-installation material properties. The alteration in the soil state of stress is represented by the increase in
the post-installation horizontal to vertical stress ratio, K*, as a function of the inter-column spacing. It is found that this alteration experiences a systematic decrease in its magnitude
as the inter-column spacing increases. 相似文献
5.
虾塘赤潮灾害的防治对策 总被引:2,自引:1,他引:2
本文报道了一次虾塘赤潮的防治过程,结合国内外有关赤潮防治的动态和作者的经验,提出了一些为避免虾塘内发生赤潮的防治对策。 相似文献
6.
加入WTO对中国旅游业的影响及应对措施 总被引:1,自引:0,他引:1
加入WTO必然对中国旅游业的发展产生重大影响,既包括创造机遇,也包括提出挑战。对此,应采取加快体制改革、留住高素质的旅游经营管理与服务人才、积极学习和借鉴国际旅游业先进的经营管理模式和经验、适时调整旅游业的产业对策,宣传中华民族文化、抓住奥运旅游的机遇,创造中国旅游的新品牌等应对措施,使得中国旅游业步入按国际惯例办事的轨道。 相似文献
7.
1 .IntroductionEpicontinental sea or land could formfromcontinental shelf because of the decreasing sea levelduring Quaternary.There is a large-area shell sand deposit more than ten meters thick in the neriticzone of China .To use the abundant marine shell sandresource as engineering material for ocean engi-neering and port engineeringis veryimportant .Sand (Gred and Bjorn,1999) ,fine sand (Zhangetal .,2002) , mediumand coarse sand (Qiuet al .,1995) ,highly weathered stone ballast (Zhanetal… 相似文献
8.
在城区化过程中,由于人口快速成长且集中,随之而来的建筑物、道路等不透水面密度增加,导致地下水补给减少及破坏水文循环。为了解土地利用方式改变对长期水文量影响,建立一个适宜的城区水循环模式是非常重要的。选定台湾台北的六馆抽水站集水区进行分析,模式参数经过敏感度分析、率定与验证。采用改变不同透水铺面设置比例的方案,评估其对径流量、入渗量、蒸发散量的改变。并分析设置不同比例屋顶雨水贮集系统对地表径流量及供水量的改变。所建立的城区水循环模式是评估土地利用改变造成水文量的改变的一个有效工具,并可提供决策者做为城区土地利用决策的参考。 相似文献
9.
山西省太谷县地质灾害及防治 总被引:2,自引:1,他引:1
太谷县地质构造条件复杂,地质灾害破坏严重,随着地区的经济发展,其城镇建设与地质灾害之间的矛盾日益突出。调查显示,太谷县发育地质灾害92处,区内地裂缝占灾害点总数46.7%,主要发育于平原区;不稳定斜坡占灾害点总数32.6%,滑坡占灾害点总数12.0%,且80%为土质滑坡;泥石流以沟谷型为主,占灾害点总数5.4%;崩塌占灾害点总数3.3%。论文研究了区内地质灾害的基本发育特征及其诱发因素。依据地质灾害防治评估划分原则,对不同类型地质灾害按轻、重、缓、急进行分期防治,对重要地质灾害采取具有针对性的工程措施治理。结合地质灾害调查分析,提出了建立群测群防网络、因地制宜、因灾设防等防治对策,为增加防灾减灾效益、环境效益及经济效益提供有力的保证。 相似文献
10.
广东省五华县地质灾害形成特征及防治对策 总被引:6,自引:0,他引:6
罗迎新 《中国地质灾害与防治学报》2008,19(3):96-101
五华县主要地质灾害类型有滑坡、崩塌、地面塌陷、水土流失等。其中以滑坡、崩塌为主,多分布在东南、南部花岗岩区、北部花岗岩风化土区等广大中低山及丘陵区,具有点多面广,灾害点个体规模小,稳定性差,活动频繁,地质灾害发育呈明显的地域性与季节性分布等特点。五华县地质灾害的形成与发生是多种致灾因素相互作用的结果。地层岩性是其形成的内在要素,它在一定程度上决定着地质灾害的发育程度与类型;地形地貌与植被是地质灾害形成的外在条件,它制约着崩、滑、塌等致灾地质作用的形成;大气降雨是地质灾害形成与发生的激发因素,决定着地质灾害发生的速度和时间;人类工程活动是影响地质灾害形成与发生的最主要、最直接的因素。对地质灾害的防治应采用避让、预防、监测及治理措施,做到避让与治理结合,以群测群防为基本手段,点状灾害以工程治理与生物防治为主;面状灾害以生物防治为主;采用点、面结合综合治理的方法。 相似文献