复杂条件下浅埋暗挖地铁车站施工地表沉降规律分析

文章以沈阳地铁中街站大跨度隧道工程为研究对象,应用FLAC3D计算软件,对复杂条件下浅埋暗挖大跨度隧道引起的地表沉降变形特征进行了数值模拟。根据洞桩法施工开挖方案,紧密结合工程实际,将动态施工开挖过程划分五个工况进行模拟,分析各施工工况对地表变形的影响和分布规律,并按工程信息化施工要求事前将预测数据提供施工单位,以指导施工控制地表沉降。模拟结果表明,采用洞桩法开挖施工过程中,对地层土体扰动较大,明显影响隧道中心附近地表变形的步序是小导洞开挖和初期支护扣拱施工阶段,约占最终沉降量的70%;而其他步序影响较小。最终,地表沉降在隧道横向分布呈"W"形态。模拟结果与现场监测数据具有较好的拟合性,表明利用数值分析方法预测大跨度隧道施工期地表沉降是可靠的。     

沉管隧道穿越江河海湾的优越性

文章从工程的造价、质量、工期、安全、生态环境及社会效益等角度,通过对沉管隧道与桥梁、盾构隧道渡越方案的分析、对比和论证,着重指出采用沉管隧道方案穿越江河海湾的诸多优越性.     

海峡西岸经济区经济发展水平与差距分析——基于与长三角、珠三角的对比

本文从人均GDP和产业结构等角度对海峡西岸经济区（福建）与长三角（上海、江苏、浙江）、珠三角（广东）的经济发展水平做了静态和动态的比较分析,寻找     

拖带大型无动力船舶通过内河桥梁水域关键技术分析

通过对大型无动力拖带船队的运动特点,内河桥梁水域通航环境的特点以及大型船队操纵的复杂性进行分析,以拖带5.7万t级无动力海船通过南京长江大桥为例,对大型无动力船拖带船队的拖船配置、拖带方式、起拖时机、拖带演习、拖航期间的安全维护、拖带作业的注意事项和应急预案等关键技术进行分析.     

机务段实行轮包结合制的探讨

针对内燃，电力机车运用中采用包乘制，轮乘制的优缺点及存在的主要问题，提出了轮包结合制。介绍了轮包结合的形式，优点，存在的主要问题，保证措施选择的原则。     

Network Decomposition and Maximum Independent Set Part Ⅰ:Theoretic Basis

IntroductionItisofsignificanttheoreticalmeaningtofindthemaximumindependentsetwithinanetwork .Thisisnotonlyrelatedtoclique ,nodecovering ,coloringandmatchingissues ,butalsoassociatedwithmanycombinatorialoptimization problems .In practicalapplications ,find…     

预制钢筋混凝土桁架拱桥的设计与施工

以一座五跨(5×30m=150m)钢筋混凝土桁架拱桥为工程背景,介绍了预制钢筋混凝土桁架拱桥的设计和施工中需要考虑的一些主要问题。     

Network Decomposition and Maximum Independent Set Part Ⅱ：Application Research

According to the researches on theoretic basis in part I of the paper，the spanning tree algorithms solving the maximum independent set both in even network and in odd network have been developed in this part，part Ⅱ of the paper．The algorithms trans form first the general network into the pair sets network，and then decompose the pair sets network into a series of pair subsets by use of the characteristic of maximum flow passing through the pair sets network．As for the even network，the algorithm requires only one time of trans formation and decomposition，the maximum independent set can be gained without any iteration processes，and the time complexity of the algorithm is within the bound of O(｜V｜^3)．However，as for the odd network，the algorithm consists of two stages．In the first stage，the general odd network is transformed and decomposed into the pseudo-negative envelope graphs and generalized reverse pseudo-negative envelope graphs alternately distributed at first；then the algorithm turns to the second stage，searching for the negative envelope graphs within the pseudo-negative envelope graphs only．Each time as a negative envelope graphhas been found．renew the pair sets network by iteration at once．and then tum back to the first stage．So both stages form a circulation process up to the optimum．Two available methods，the adjusting search and the picking-off search are specially developed to deal with the problems resulted from the odd network．Both of them link up with each other harmoniously and are embedded together in the algorithm．Analysis and study indicate that the time complexity of this algorithm is within the bound of O(｜V｜^5)．     

网络分解及最大独立集算法研究（Ⅰ）

本文首先分析了一般网络的结构特征，开发出对任意网络进行变换及分解、且不丢失可行解的新方法，继而发现了网络中具有优化迭代功能的特殊子网络；对其进行了较深入的研究，提出并论证了求最大独立集的充要条件：研制出在网络中系统搜索该特殊子网络的新算法。最后，对算法的有效性及可靠性，进行了较全面的分析论证，研究表明，该算法可在时间复杂性O(|V|^5)界内收敛。