高速公路软基路堤临界高度研究

在软土地基上修筑高速公路存在路堤临界高度的问题，根据某高速公路的现场实测数据，探讨了临界高度对软基沉降、侧向位移的影响。分析结果表明：路堤填筑到临界高度以后，软基的沉降量、沉降速率、侧向位移量都急剧增大。最后，应用遗传神经网络算法来计算路堤临界高度，并结合工程实例验证了该算法具有较高的预报精度。     

CFG桩在公路软基处理中的应用

通过河北省沿海高速公路沧州岐口至海丰段第四合同路基软基处理中CFG桩的施工,对CFG桩的应用、工艺分类及其特点进行了分析,并就振动沉管打桩机成孔制桩（挤土成桩）的施工工艺、工序及控制要点、常见问题分析及措施、质量检验等环节进行了阐述。     

混凝土连续弯梁桥侧向位移分析及对策研究

混凝土连续弯梁桥出现的爬移问题日渐引起了工程界的重视,针对此问题,分析了混凝土连续弯梁桥产生侧向位移问题的主要原因,包括弯梁桥的曲率半径、恒载作用、支座布置形式、温度变化影响、活载作用、梁的截面形式、下部构造特征、混凝土的收缩徐变以及预应力施工等因素,进一步从设计和施工方面提出了一些相应的预防爬移问题的处理措施,以防止弯梁桥出现爬移现象。     

Bucket Group Effect of the Composite Multi-bucket Structure

As a novel type of foundation in beach and shallow sea,the bucket structure is especially suitable for complex conditionssuch as soft clay ground and the worse types of sea environments.In this paper, the bearing capacity of a multi-bucket structure isstudied by experiments with a single bucket and four-bucketfoundation in a saturated sand layer. Based on the experimentaldata and numerical analysis results, the bearing capacity behaviorand the bucket group effect are compared and analyzed.Furthermore, some influential factors, such as the soil type, theratio of length to diameter L/D, the ratio of the bucket spacing tothe bucket diameter S/D, and the bucket number are introduced andtheir effects on the multi-bucket structural capacity are investigatedThe vertical static capacity adjustment factor is introduced toevaluate the bucket group effects of the multi-bucket foundation.     

Prediction of hull girder moment-carrying capacity using kinematic displacement theory

The hull girder moment capacity of a very large crude oil carrier (VLCC) called Energy Concentration (EC), for which many benchmark studies have been carried out using the simple progressive collapse method (SPCM), is predicted. In this study, three approaches are used to represent the load-shortening behavior, so-called average compressive strength, of a stiffened panel, comprising the hull section: 1) kinematic displacement theory (KDT); 2) nonlinear finite element analysis (FEA); and 3) simple formulas in the common structural rule (CSR) for tankers. Load-shortening curves for various kinds of stiffened panels in EC are compared for five different scenarios with variations of load-shortening approaches and initial imperfections. In order to verify the effect of load-shortening on the prediction accuracy of the hull girder moment-carrying capacity, load-shortening curves are imported into an SPCM-based in-house program called Ultimate Moment Analysis of Damaged Ships (UMADS). Comparison of the hull girder ultimate strength for general heeling conditions, including hogging and sagging conditions, reveals that the load-shortening curves significantly affect the hull girder moment-carrying capacities. Based on our comparison of these capacities with other benchmark results, it is concluded that nonlinear FEA provided the most conservative results, KDT provided the second most conservative results, and the CSR formulas predicted the upper bound.     

广州地铁暹岗站的抗浮计算分析

抗浮计算是地下地铁车站设计的重点,而计算参数、计算模型的选取对抗浮计算结果有较大影响。抗浮计算中部分参数的选取尚无统一规定,且使用阶段结构底板,尤其是轨道范围内的位移控制尚未引起足够重视。针对广州地铁暹岗站抗浮设计,选取适当的计算参数及公式,并采用有限元结构计算软件分析结构底板位移,最终合理确定结构相关抗浮方案。在满足抗浮的同时,车站底板不仅需要满足结构挠度要求,还需要考虑使用阶段的结构位移。可采用有限元计算软件进行模拟计算。     

圬工拱桥上部结构合理拆除方案研究

为了保证圬工拱桥的桥墩在改造过程中不被破坏,应选择合理的上部结构拆除方案.结合一座3跨连续圬工拱桥,在上部结构拆除过程中,对桥墩进行受力分析,得出墩顶的水平位移和墩底截面的最大应力(最大压应力和最大拉应力),以选择合理的拆除方案.     

浅谈江阴大桥大位移桥梁伸缩缝的施工工艺

近年来随着我国桥梁设计和施工水平的不断提高,一些跨径超千米的特大型桥梁的修建不断增多,同时对这些桥梁使用的大位移桥梁伸缩缝的设计和安装也有了很高的要求。以江阴长江大桥DS2000型转轴式桥梁伸缩缝的更换安装工程为例,全面系统地介绍了旧缝拆除、新缝安装的施工要点及施工工艺。     

舟山跨海大桥桥上安全行车风速研究

受大桥通航净空的限制,舟山跨海大桥桥面高程高、风速大以及桥梁本身的结构特点,使得车辆的行驶环境大为改变,影响行车安全.本文通过对不同速度下车辆所受风力及影响行车安全外力的综合分析研究,计算不同车速下跨海大桥上车辆的安全行车风速,为跨海大桥运营期限速指标的确定提供理论分析依据.     

桥梁动位移测试的数字处理方法研究

提出了采用MEMS加速度传感器进行动位移测试整体算法框架,即对测量的加速度信号进行板上软件滤波和积分处理进而得到桥梁的动位移.设计了各环节的算法并分析其性能,进行了实际测试的对比研究,成功地处理了天津汉沽蓟运桥现场试验数据.研究表明:采用该传感器进行桥梁动位移测试稳定性好,可靠性高.该研究时桥梁动态监测工作有重要的实用...