共查询到19条相似文献,搜索用时 937 毫秒
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介绍了最新研制的水下软基处理船。其中包括塑料排水板插设、土工布铺设、水上定位和电脑监测记录方法和装置等。该船适用于多种水下软基处理工程,解决了深水塑料排水板加固软基的方法和设备问题。 相似文献
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为了有效控制软土地基上海岸建筑物的工后沉降和不均匀沉降,各种软基处理方法在海岸工程建设中得到了越来越广泛的应用。结合海岸工程软土地基处理实例,对振冲挤密法的地基加固机理、加固砂类土地基时的设计参数、施工及加固后地基的检测等进行了探讨,结果表明,振冲挤密处理砂类土地基是行之有效的,并对今后的施工和设计提出了一些参考性建议。 相似文献
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围海造陆填土技术及其应用研究 总被引:1,自引:0,他引:1
《中国海洋大学学报(自然科学版)》2015,(6)
提出了在填土工程中将海底的淤泥和吹填料中的淤泥聚集在一起,最终将新形成的陆域分离成以粗粒土为主的非软土地基和以淤泥质土为主的软土地基两个区域,继而可以针对各分区的地基选用不同的加固处理方法的围海造陆填土技术观点;基于土力学的强度理论和水力吹填的分选性,提出了能够实现填土技术观点的思路与基本条件;将本文提出的围海造陆填土技术观点、陆域形成填土技术成功应用于日照岚山港区围海造陆工程。 相似文献
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本文阐述了海洋工程水下软土地基加固处理的实用方法:振冲法、真空预压法、高压旋喷法、爆破法、土工织物法、强夯法以及水泥石灰系拌和法.并对这些方法的施工研究及注意问题进行了专题详述. 相似文献
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水下管道穿越一段淤泥覆盖层很厚的区域,需在松软土壤上建造管道基础。用土工织物加固土壤是一种新型管道基础施工技术,在淤泥与砾石之间铺放土工织物,能起到加固软土、提高管道稳定性的效果。本文论述了土工织物加固软土基础的工作机理,通过有关计算及试验证明:土工织物具有提高土壤承载强度、减小沉降量的工程效果。针对水下管道基础的特殊形式,提出了其结构的设计要素,诸如:土工织物的选择、基础宽度和高度的确定等,并介绍了几种土工织物的水下施工方法和施工中应注意的关键环节。最后,通过某一水下管道工程用土工织物和桩两种基础处理形式的比较和技术经济评价,认为:土工织物处理水下管道基础具有费用低廉、施工简单的优点。 相似文献
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以阿尔及利亚储罐软基处理工程为背景,介绍了振冲碎石桩与充水预压加固软土地基的现场试验,通过对储罐地基充水预压期间所作的实测资料进行分析,论述了该项技术加固油罐地基的效果,探讨了地基沉降、环墙内侧土压力、孔隙水压力等的变化发展规律;针对油罐外深层的增量位移,利用轴对称有限元方法进行数值模拟和分析,辅助分析了地基变形。分析结果表明:振冲碎石桩与充水预压联合加固处理软弱地基是合理可行的,该油罐平面倾斜、非平面倾斜满足规范的地基变形允许值,有限元数值模拟可以应用于辅助分析地基变形。 相似文献
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L 港是我国的重要港口之一,港口自然条件比越。但也存在着陆域狭小,港口回淤量大、软土地基处理困难的问题。为了开发港口资源,本文对1934年建港以来,港口地基处理中的主要问题和经验进行了调查总结,并提出了一些肤浅的看法。文中首先评述了港口工程地质条件,然后对过去修建码头、防波堤和护岸工程所发生的地基事故和成功实例进行原因分析,最后提出 L 港口工程软土地基处理的有效方法及其建议。 相似文献
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塑料排水板超载预压法处理软基在环胶州湾公路工程中的应用 总被引:1,自引:0,他引:1
塑料板排水法是近年来在软基处理中应用较广泛的一般方法。本文结合环胶州湾公路工程实例,介绍了塑料排水板超载预压法处理软基的施工方法。 相似文献
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针对现阶段深水软黏土地基防波堤建设的设计理论和稳定性分析方法尚不成熟,结合实际工程,采用三维弹塑性有限元数值分析方法,研究在水平或竖直单一方向荷载以及复合加载条件下软黏土地基上沉箱防波堤的失稳模式,提出破坏包络线的稳定性判别方法。在波浪水平荷载作用下,深水软基上沉箱防波堤发生倾覆失稳破坏,失稳转动点为沉箱底面以下中轴线偏右的某点,不同于规范中规定的岩石或砂质地基沉箱倾覆转动点为其后踵点;在重力等竖向荷载作用下,沉箱的失稳模式为结构整体下陷,抛石基床及地基形成连贯的塑性区域,呈现较明显地冲剪破坏形式;在水平、竖向复合荷载作用下,软基上沉箱防波堤的破坏包络线由结构倾覆破坏线和地基承载力破坏线组成,包络线将荷载组合区分成稳定区、仅发生水平承载力不足倾覆破坏区、仅发生地基竖向承载力不足破坏区、同时发生水平承载力和地基竖向承载力不足破坏区4个区域。研究成果为深水软基沉箱防波堤建设提供参考和借鉴。 相似文献
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Under the effect of eccentric loads,when the suction pressure of the composite bucket foundation is leveled,the seepage failure is very easy to occur.The seepage failure occurrence causes the foundation to settle unevenly and impairs the bearing performance.This study uses ABAQUS finite element software to establish a composite bucket foundation model for finite element analysis.The model simulates the seepage of the foundation penetrating process under eccentric load to reveal the induced seepage characteristics of the bucket foundation.The most vulnerable position of seepage failure under the eccentric loading is elucidated.Critical suction formulas for different offset eccentric moment strategies are derived and compared with existing literature formulas.Then the derived formula is supplemented and corrected according to the pressure difference between adjacent cabins.Conclusions can be drawn:(1)Under eccentric loads,the critical suction decreases about 7%?10%.(2)The pressure difference between adjacent cabins impacts significantly on the seepage field,and the critical suction,at most,can be reduced by 17.56%.(3)the offset strategies have little effect on the seepage field.Efficient and appropriate strategies can be selected to meet the requirement of leveling in engineering project. 相似文献
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AbstractPile foundation is the most popular option for the foundation of offshore wind turbines. The degradation of stiffness and bearing capacity of pile foundation induced by cyclic loading will be harmful for structure safety. In this article, a modified undrained elastic–plastic model considering the cyclic degradation of clay soil is proposed, and a simplified calculation method (SCM) based on shear displacement method is presented to calculate the axial degradated capacity of a single pile foundation for offshore wind turbines resisting cyclic loadings. The conception of plastic zone thickness Rp is introduced to obtain the function between accumulated plastic strain and displacement of soil around pile side. The axial ultimate capacity of single piles under axial cyclic loading calculated by this simplified analysis have a good consistency with the results from the finite element analysis, which verifies the accuracy and reliability of this method. As an instance, the behavior of pile foundation of an offshore wind farm under cyclic load is studied using the proposed numerical method and SCM. This simplified method may provide valuable reference for engineering design. 相似文献
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When studying the low-cycle fatigue crack initiation life of notched plates, the effects of fatigue short crack and accumulative plastic damage in the vicinity of the notch should be considered. The low-cycle fatigue crack initiation life of notched plates has been revised in the analysis process by considering the short crack initiation and expansion of notch stress concentration area. By determining the accumulative plastic deformation in the vicinity of a notch under low-cycle fatigue loads, a predictive model of low-cycle fatigue crack initiation life was presented for notched plates, and the relative influence factors were quantitatively analyzed. A comparison study verified that the results obtained from the presented calculation model correlate quite well with those from the existing experiments. Some important conclusions were drawn from the study on considering the effects of short crack and accumulative plastic damage. The presented method may be used for predicting the low-cycle fatigue crack initiation life of ship plate. 相似文献
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Large diameter monopiles are typical foundation solutions for offshore wind turbines. In design of the monopile foundations in sand, it is necessary to understand the drainage conditions of the foundation soil under the design loading conditions as the soil performance (strength and stiffness) is highly dependent on the drainage conditions. This paper presents a numerical investigation into this issue, with a purpose to develop a simple design criterion for assessing the soil drainage conditions around a monopile in sand. It is found that for typical monopile foundations in sand, the drainage condition during a single load cycle is generally expected to be undrained. However, the current state-of-practice uses p-y springs derived for drained soil responses for monopile design. The impact of this discrepancy on monopile foundation design was evaluated and found to be insignificant due to the relatively low level of loading as compared to the capacity of the soil. 相似文献