共查询到12条相似文献,搜索用时 62 毫秒
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针对重力式码头CAD系统开发中存在的设计荷载处理的技术难题,提出了一种切实可行的计算机解决方案,并提供了CAD系统常用的数据接口技术。该方案有较强的应用价值,可作为开发各类重力式码头CAD系统的借鉴。 相似文献
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由于作用荷载复杂,沉入式大圆筒码头结构设计计算需要考虑不利情况下的各种荷载组合,难以应用现有的有限元加载系数法进行稳定性分析。有限元强度折减法目前已广泛应用于土体边坡稳定性分析。沉入式大圆筒结构的抗滑、抗倾稳定性是靠地基土的嵌固作用来维持的,可通过弱化土体强度来实现对结构极限破坏状态的模拟。在此假设基础上,建立沉入式大圆筒码头稳定性分析的有限元强度折减法。结合某工程实例,利用有限元强度折减法分析沉入式大圆筒码头结构的稳定性。强度折减法只需对土体的强度进行弱化,操作方便,克服了加载系数法的缺点,适用于码头等作用荷载复杂的结构物稳定性分析。 相似文献
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This article presents an approach for estimating land subsidence due to withdrawal of groundwater. The proposed method calculates the groundwater seepage in 3-D-condition and calculates the land subsidence one-dimensionally. The governing equation on groundwater seepage is based on the three-dimensional mass conservation law and the principle of effective stress. The land subsidence calculation method is derived based on the following assumptions: (1) displacements occur only in the vertical direction, and (2) in vertical direction the total stresses do not change. The governing equation is solved by numerical method, i.e., finite element method (FEM) in spatial discretization and finite difference method (FDM) in time series discretization. In FEM Galerkin method is adopted and in FDM, lumped matrix method is employed. The proposed method is calibrated via analyzing 1-D consolidation problem and the results are compared with those from Terzaghi's one-dimensional consolidation theory and oedometer test. The proposed method is employed to analyze the consolidation of a soft layer due to withdrawal of groundwater from an aquifer under it. Moreover, this method is also applied to a field case of land subsidence due to groundwater pumping in a gas production field in Japan. The analytical results are compared with the field observed data. The results show that this approach simulates the field case well. 相似文献
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Estimation of Land Subsidence Based on Groundwater Flow Model 总被引:8,自引:0,他引:8
This article presents an approach for estimating land subsidence due to withdrawal of groundwater. The proposed method calculates the groundwater seepage in 3-D-condition and calculates the land subsidence one-dimensionally. The governing equation on groundwater seepage is based on the three-dimensional mass conservation law and the principle of effective stress. The land subsidence calculation method is derived based on the following assumptions: (1) displacements occur only in the vertical direction, and (2) in vertical direction the total stresses do not change. The governing equation is solved by numerical method, i.e., finite element method (FEM) in spatial discretization and finite difference method (FDM) in time series discretization. In FEM Galerkin method is adopted and in FDM, lumped matrix method is employed. The proposed method is calibrated via analyzing 1-D consolidation problem and the results are compared with those from Terzaghi's one-dimensional consolidation theory and oedometer test. The proposed method is employed to analyze the consolidation of a soft layer due to withdrawal of groundwater from an aquifer under it. Moreover, this method is also applied to a field case of land subsidence due to groundwater pumping in a gas production field in Japan. The analytical results are compared with the field observed data. The results show that this approach simulates the field case well. 相似文献
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针对胜利油田埕岛海域海床土体强度的非均匀性和可能引起的海底管线差异沉降破坏,提出1种海底管线差异沉降安全性分析方法.具体介绍差异沉降产生的原因,通过分析管线的受力状态,建立管线因差异沉降引起的附加应力的表达式.针对黄河水下三角洲埕岛油田常见的3种规格管线,建立不同土质条件下的管线附加应力表格,方便工程师查询.考虑附加应力和流体对管线的应力,与管线材料的允许应力比较,可以判断管线的安全性. 相似文献
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IDL语言拥有强大的数据处理与图形显示功能,它能使开发者使用很少的命令完成大量的工作。根据这个特点,使用IDL语言进行二次开发,实现了原始地面沉降观测数据的规则化、各种形式的静态可视化显示,并利用数字方法得到各个时段的帧数据,将这些帧数据按时间序列进行可视化显示,即实现了地面沉降的动态模拟。 相似文献
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Interaction between Climate Changes, Eustacy and Land Subsidence in the North Adriatic Region, Italy 总被引:4,自引:0,他引:4
Abstract. The North Adriatic coastal area has experienced a serious relative sea level rise whose main component is land subsidence. Geological regional subsidence is ascribable to compaction and to deformation of substratum. Anthropogenic subsidence, which is due to ground fluid removal, has been severe in the second half of the 19th century, reaching values in meters. It is without doubt the main factor responsible for the instability of the entire coastal ecosystem. Widespread retreat of shoreline, seawater invasion, decay of vegetation, changes in the habitat of the flora and fauna have occurred. Sea level rise alone is linked to climate changes, which exhibit fluctuations of the order of a few hundred years; here, cold-wet periods alternated with warm-dry periods and, within them, shorter cold-wet and hot-dry cycles lasting for decades also alternated. 相似文献
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大体积混凝土是指最小断面尺寸大于1m的混凝土结构,而且其尺寸已经大到必须采取相应的技术措施妥善处理温度差和合理解决温度应力问题并控制裂缝扩展,因此,大体积模注混凝土的表面质量通病的防治是施工质量控制的一项重要内容。对大体积混凝土表面质量通病的形成原因和防治措施进行了探讨。 相似文献