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岸坡码头中高承台桩基,其受力特点复杂,是一个典型的被动桩与岸坡相互作用问题。本文采用有限元数值模拟计算,研究了高承台桩基和岸坡土层共同作用的应力和变形,而且进行了多断面的方案比较研究,计算结果很好的反映出了高承台桩基受力变形特点。进而总结出高承台桩桩土共同作用变形的几点规律。 相似文献
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通过4组特高心墙坝岸坡接触黏土层离心模型试验,分析了岸坡不同位置处接触黏土与心墙在坝体填筑加载过程中的变形,以及变形在竣工后的发展情况。试验结果表明:接触黏土层与岸坡、心墙土体之间的相对变形较小,没有分离现象,变形协调性较好;上覆荷载引起接触黏土产生垂直岸坡的压缩变形和平行岸坡的剪切变形,压缩和剪切变形均随荷载对数线性增加,接触黏土始终处于压剪状态;变形随荷载的发展程度,在坝基坡度较缓时较小,坝基坡度较陡时较大,在坝基坡度变化处则介于两者之间;接触黏土层的变形在竣工后渐趋稳定。 相似文献
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三峡库区奉节新县城库岸边坡类型及岩体结构特征 总被引:6,自引:0,他引:6
奉节新县城库岸边坡自三峡水库蓄水至139 m水位以来多处出现变形破坏,库岸段岸坡变形破坏模式的复杂多样给相应的工程治理带来了较大的困难。通过研究奉节新城区库岸段岩土体类型和岩体结构特征,将新县城江北片区21.7 km的库岸划分成21个库岸段,明确了基岩岸坡和土石岸坡的分布范围,确定了库岸边坡的结构类型。针对不同的岸坡结构类型,分析了岸坡可能出现的6种变形破坏模式。岩质边坡可能出现弯曲–拉裂–倾倒型、剪切–滑移型、楔形体崩塌–滑动型和风化–剥落型变形破坏;土石岸坡可能出现弧形整体滑动型、局部剪切破坏或崩塌型变形破坏。以库岸段的可能变形破坏模式为基础,有针对性地分段采取相应工程治理措施,有利于保证库岸防治达到预期效果。 相似文献
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岸坡码头中高承台桩基,其受力特点复杂,是一个典型的被动桩与岸坡相互作用问题。本文采用有限元数值模拟计算,研究了高承台桩基和岸坡土层共同作用的应力和变形,而且进行了多断面的方案比较研究,计算结果很好的反映出了高承台桩基受力变形特点。进而总结出高承台桩桩土共同作用变形的几点规律。 相似文献
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针对谷拉河特大桥库淹区斜坡桥基础稳定性问题,采用离散元法建立了岸坡数值仿真模型,分析了正常施工期和蓄水期两种工况下岸坡的水平、竖直及沿岸坡度方向的位移,研究了不同工况下岸坡变形规律.结果表明:在施工期,岸坡基本能保持稳定,仅局部块体滑动位移较大,而在蓄水期大部分块体的滑动位移明显增大,说明水对岸坡的稳定性有着直接的影响,需要结合工程实际采用灌浆、加固及设置排水设施等综合治理方法对其进行处治. 相似文献
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结合奉节缓倾层状岸坡的特点,分析认为软硬相间的岩性组合、近水平的岸坡结构,加之垂直层面的密集短小节理的切割构成了奉节地区独特的岸坡结构形式。岸坡变形破坏主要以压致拉裂、差异卸荷、重力蠕变-滑移-倾倒和结构沉陷等4种模式进行。巴东组第二段(T2b2)紫红色泥岩的易风化,崩解特性以及第三段(T2b3)泥灰岩的脆性,易溶蚀特性使得该区边坡岩体结构被深度改造,导致岩体结构沉陷,使得岸坡出现了似滑非滑、似塌非塌的变形破坏特征,存而导致了关于其破坏模式认识上出现了很大争议。 相似文献
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库水位升降作用下三峡库区土质岸坡坡体吸水、应力集中及滑移变形,形成不同时段和不同空间部位的裂缝体系。通过模型试验的方法,分析了土质岸坡在一个蓄水降水循环周期内裂缝体系的时空演化分期配套规律。试验结果表明:蓄水初期,裂缝主要出现在岸坡前缘水位线附近,且出现频率高、规模逐渐增大,岸坡出现局部坍塌破坏;蓄水中期,岸坡前后缘均有裂缝出现,但出现频率低、规模减小;蓄水后期,前缘裂缝发育基本消失,后缘裂缝继续发育,岸坡以沿滑动面整体蠕滑为主;水位上升过程中暂停蓄水时裂缝发展缓慢。降水阶段,拉张裂缝主要出现在岸坡坡体后缘,初期降水裂缝出现频率较低,发展缓慢;后期降水裂缝出现频率、规模变大,产生下座变形及下错台坎;水位下降阶段岸坡沿滑动面发生整体缓慢蠕滑。 相似文献
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结合目前高速公路施工项目招投标活动的实际情况,阐述了最低评标价法的概念,归纳了其优点及存在问题,对完善最低评标价法提出几点策略,以期促进招标投标市场更加规范有序。 相似文献
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This article analyses state-led place-making practices in Melbourne. The two levels of government that influence planning in Melbourne make much of the city as ‘culturally vibrant’ and ‘creative’, and have incorporated creative city-inspired place-making principles into many layers of the planning system. An examination of the development of two mixed-use megaprojects in central Melbourne reveals however that ideals of culturally engaging public places, and indeed of creative landscapes for middle-class consumption, wither in the face of more basic imperatives for economic development. In these case studies the ‘creative city’, no matter how the idea is interpreted, has little traction either as a set of inclusive place-making principles or as a gentrification strategy. The article concludes that the creative city-inspired place-making objectives in the planning system at both state and local levels are ambiguous in their overall intents and completely unsupported by statutory controls. Such place-making objectives as are realised are the compromised results of the interplay of uncoordinated decisions, delivered at the pleasure of the developer. 相似文献
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Vo Thi Yen-Phi Andrea Rechenburg Joachim Clemens 《The Science of the total environment》2010,408(9):2050-2053
Septage is widely acknowledged as a major source of infectious pathogens while disposal of septage, and the operation and maintenance of septic tanks, is not regulated in many developing countries. Twenty untreated septage and septage sludge samples were taken from Can Tho City, Vietnam to examine their pathogen content, and indicator micro-organisms. Escherichia coli and Enterococcus spp. were detected in all samples, regardless of sludge storage time. Phages were detected in 80% of samples. Salmonella spp. were detected in 70% of the untreated septage and 60% of septage sludge samples. Concentrations of phages and bacteria tested in septage sludge after many years of tank storage were much higher than the expected levels. Helminth ova were present in 95% of untreated septage samples with an average of 450 ova l− 1, and were detected in all septage sludge samples with an average of 16,000 ova l− 1. Twelve varieties of helminth ova were identified. More helminth ova varieties in higher concentrations were found in septage than those reported from stool samples. The varieties' frequency ranged from 10% to 50% and Ascaris lumbricoides predominated. Results show that pathogens and indicator micro-organisms, especially helminth ova, accumulate in sludge. Thus helminth ova should be considered when septage sludge is treated and used for agriculture. Proper health protection measures must be applied for people handling septage. 相似文献
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近两年来,工程公司在提高市场竞争意识、推动市场化进程中做了大量工作,其中坚持走出去的方针是我们自我加压、推行加快市场化步伐的一个重要战略步骤。 相似文献
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新时期广东城市化的新特点 总被引:4,自引:0,他引:4
新时期广东城市化出现以下特点:知识源导向、城市由单体向群体化发展、产业集群推动、政府主导自上而下的集约化发展、城镇化向城市化转变、由重“数量”发展向重“质量”发展的转变。 相似文献
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《Planning》2022,(5)
在市场条件下高校基建财务人员在加强日常财务管理的同时,必须树立起高度的工作责任心,抓好事前监督、事中监督、事后监督三个环节,全面理解、贯彻执行《高等学校财务制度》,管好用好各项基本建设资金,提高基建财务管理水平,更好地完成高校各项基建任务,以有限的投资,最快的建设速度,获得最大的投资效益。 相似文献
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北京中原房地产经纪公司市场研究部 《建设科技(建设部)》2005,(4):47-48
趋势一:CBD区域写字楼集中放量从各区域规划方案上看,CBD区域多数项目在03~04年处于项目的报批手续及拆阶段,预计2005年正式推向市场,因此2005年CBD区域将成为北京市场供应集中的域,区域即将供应的项目有北京财富中心(二期)、金地国际花园、万达广场、SOHO尚都、万通中心、世纪财富中心、怡禾国际中心、光华国际等。除去未知项目,2005CBD写字楼办公面积的供应量为60万平方米左右。中关村区域经过一段时间的集中供后开始逐步放缓,2005年供应的体量相对较大的项目有中关村金融中心、新中关。金街区域可能开盘的项目只有2个:英蓝国际中… 相似文献
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浅谈我国工程项目建设成本控制存在的问题 总被引:2,自引:0,他引:2
结合目前我国施工企业工程项目成本管理现状,对工程项目成本管理过程中存在的问题进行了较详细的分析,并提出了一些解决问题的办法,以做好项目成本控制工作,进而增强企业经济实力。 相似文献
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Jesse E. Raine 《The Annals of Regional Science》1972,6(1):135-144
Conclusions It may be reasonably concluded from this study that the range of variation in these ratios of assessed to actual value are of a reasonable size for the great majority of cases. The frequency distribution of these sample ratios was not normal, however, as was assumed a process of this type would produce. On the other hand, the failure of the regression analysis to identify any significant variables which would explain these variations would tend to re-enforce the assumption that the fluctuations were indeed of a random nature.To sum it up in one paragraph, aside from a few extreme cases, the assessing process appears to give estimates which are more consistent than would be expected under the assumption that any errors would be of a random nature, but the regression analysis was unable to isolate any particular socioeconomic characteristics which would explain the variation which was present.Financial support for this research project was furnished by the University of Tulsa. 相似文献