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901.
Post-tensioned concrete rocking walls might be used to avoid severe seismic damage at the base of structural walls, decrease residual drift, and lessen post-earthquake repair costs. The prediction of load-induced damage to the rocking wall resulting from seismic loading can provide an extremely valuable tool to evaluate the status and safety of structural concrete walls following earthquakes. In this study, the behavior and the damage state of monolithic, self-centering, rocking walls, as a new type of concrete rocking wall, are investigated. The nonlinear mechanical behavior of the wall is first modeled numerically, and subsequently the mechanical parameters from the numerical simulation are used to generate the local damage index. The results from the damage index model are compared with the full-scale test results, confirming the viability of the numerically based damage index method for estimating the seismically induced damage in concrete walls. Moreover, the estimated damage can be utilized as a qualitative and quantitative scale to assess the status of the wall following seismic loading events. Finally, an equation is proposed to estimate the repair cost based on the predicted damage state for the studied structural system. 相似文献
902.
Based on the bat algorithm (BA), this paper proposes a discrete BA (DBA) approach to optimize the disassembly sequence planning (DSP) problem, for the purpose of obtaining an optimum disassembly sequence (ODS) of a product with a high degree of automation and guiding maintenance operation. The BA for solving continuous problems is introduced, and combining with mathematical formulations, the BA is reformed to be the DBA for DSP problems. The fitness function model (FFM) is built to evaluate the quality of disassembly sequences. The optimization performance of the DBA is tested and verified by an application case, and the DBA is compared with the genetic algorithm (GA), particle swarm optimization (PSO) algorithm and differential mutation BA (DMBA). Numerical experiments show that the proposed DBA has a better optimization capability and provides more accurate solutions than the other three algorithms. 相似文献
903.
Traditional quality inspection based product quality evaluation method with complex process has high operating cost and requires more professional knowledge. To remove the above limitation, this paper leads product gene theory into product quality evaluation. Methods of quality influencing factors based modeling and encoding are established. Combined with similarity theory and product gene theory, a product gene similarity analysis based quality evaluation method is proposed. The proposed method is low cost, operates easily and requires less specialized knowledge. A case study is conducted to prove the correctness and feasibility of this method. 相似文献
904.
"轨道+物业"开发模式促进了城市土地集约化利用、为轨道交通建设的可持续发展提供资金保障,在轨道交通行业已形成共识。轨道交通沿线土地综合开发是当前轨道交通企业采用的主要融资模式,是中国主要城市迫切需要推行的模式。阐述对"轨道+物业"开发的认识,对深圳市土地作价出资政策、开发模式、上盖物业与轨道交通建设衔接、持有优质物业等核心问题进行详细分析。探讨未来深圳市轨道交通上盖开发面临政策调整风险、土地资源稀缺、保障性住房建设等多种挑战。最后,提出积极走市场化路线参与城市更新、建设安居型可售人才房和保障房、实施走出去战略、"轨道+物业"开发经验输出等发展策略,以实现轨道交通建设可持续发展。 相似文献
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908.
湖南省湘阴县滨江大道是县城一条重要的城市主干道。分析了提质改造中原有水泥混凝土路面加铺沥青混凝土设计的原理、设计要点、具体加铺方案及注意事项,可为类似的城市道路路面提质改造建设提供参考。 相似文献
909.
简要介绍了寒山大桥加宽工程概况。详细介绍了该桥主桥设计要点,并对该桥上部结构,包括混凝土主梁段、钢梁架设、钢管拱架设等主要施工方法进行了阐述。 相似文献
910.
该文针对沉井施工对井周边环境的影响,提出环境效益的概念,采取合理防治措施,使工程获得最佳的经济效益和社会效益。其成果可为同类型工程设计及施工提供参考。 相似文献