Structural Design Issues of Accelerated Bridge Construction in Skew and Right Alignments

使用预制构件和系统加快新桥的建造和更换破旧的桥，最近引起了桥梁司法管辖区的极大关注和兴趣。预制件和系统可以快速组装，可以减少设计工作量，减少对现场附近环境的影响，并最大限度地减少延误和车道关闭时间，以及对出行公众的不便，节省时间和纳税人的金钱。其中一个系统包括横向放置在钢或混凝土梁上的全深度、全宽度预制混凝土桥面板，其中提供了灌浆口袋，以容纳焊接到钢梁或嵌入混凝土梁的剪切连接件集群。文献回顾揭示了一些重要的未解决的分析、设计和性能问题，需要进行详细的评估。这些问题包括：(I)施工阶段预制桥面铺设过程中斜交组合桥梁的静载和活载分配系数；(Ii)极限状态和疲劳极限状态下斜交组合桥梁的活载分配系数；(Iii)货车通过斜交桥时相对于右侧斜交桥的动载裕度(冲击系数)；(Iv)横向预制板与板连接，采用玻璃纤维聚合物(GFRP)筋，头端在桥梁跨度内，以提高强度和耐久性；(6)负弯矩区GFRP加固预制横板-板-板连接，以提高组合梁在极限状态和疲劳极限状态下的抗弯强度。这项研究的目的是通过开发经过实验校准的、基于计算机的设计指南来准确预测桥梁在不同荷载下的反应，从而为使用全深度、全宽度、预制桥面板建造的桥梁的高效设计做出贡献，从而为桥梁所有者节省潜在的成本并纳入CHBDC。现场数据和全尺寸试验结果将为桥梁设计者提供有意义的反馈，导致新一代维护最少的桥梁，详细说明固有的耐久性。

The use of prefabricated elements and systems in accelerating construction of new bridges and replacement of deteriorated ones has recently been the subject of much attention and interest amongst bridge jurisdictions. Prefabricated elements and systems can be quickly assembled and could reduce design efforts, reduce the impact on the environment in the vicinity of the site, and minimize the delays and lane closure time and inconvenience to the traveling public, saving time and tax payers money. One of these systems involve full-depth, full width, precast concrete deck slab placed transversally over steel or concrete girders where grout pockets are provided to accommodate clusters of shear connectors welded to steel girders or embedded in concrete girders. Literature review revealed a number of important unresolved analysis, design and performance issues which require detailed evaluation. These issues include: (i) the dead and live load distribution coefficients for non-composite bridges in skew alignment at construction stage during precast deck placement; (ii) live load distribution coefficients for composite bridges in skew alignment at ultimate and fatigue limit states; (iii) the dynamic load allowance (impact factor) due to trucks moving over a skew bridge as compared to a right one; (iv) transverse precast panel-to-panel connection incorporating glass fibre polymer (GFRP) bars with headed ends within bridge span for strength and durability; and (vi) GFRP-reinforced precast transverse panel-to-panel connection at the negative moment region to increase flexural strength of the composite girder at ultimate and fatigue limit states. The aim of this research is to contribute to the efficient design of bridges built with full-depth, full-width, precast deck panels by developing experimentally-calibrated, computer-based, design guidelines capable of predicting accurately their response when subjected to different loading , with potentially significant cost savings to bridge owners and inclusion in CHBDC. Field data and full-scale experimental results will provide a meaningful feedback to bridge designers, leading to a new generation of minimal maintenance bridges, detailed for inherent durability.