Design of sustainable and resilient geotechnical infrastructure for transportation systems

最近的地震见证了由于地面运动、土壤液化和相关的横向扩散对桥梁和地下结构的严重破坏。新的2020年加拿大国家建筑规范规定，加拿大大多数主要城市的地震危险大大增加。特别是不列颠哥伦比亚省和魁北克-蒙特利尔-渥太华走廊是地震活跃的地区。因此，建筑环境的可持续性和弹性变得越来越重要和令人关注。关键基础设施的完整性在很大程度上依赖于其基础的性能。拟议的研究计划旨在为基础设施项目开发可持续和有弹性的深层基础和埋地结构，这些基础和埋地结构将承受环境危害并节省资源。本研究将开发、测试和分析高速公路和道路基础设施的弹性和可持续基础和埋地结构，并将评估不同深基础和埋地结构的抗震性能。该研究将使用新型振动台试验和最先进的新建立的西方岩土离心机来完成。此外，将为其设计制定创新桩方案和准则的全面测试。特别是，本研究将研究开发创新的灌浆螺旋桩，可以为桥梁基础设施提供高效和弹性的基础选择，并研究用于道路和高速公路基础设施的高效预制三面钢筋混凝土（TSRC）涵洞，并为其设计制定具体的指导方针。这一点尤其重要，因为加拿大公路桥梁设计规范（CHBDC）中规定的当前设计实践将TSRC涵洞与传统的箱形涵洞等同对待，导致过于保守和昂贵的设计。拟定的设计指引将提交有关的委员会审议，以纳入下一版本的守则。本文还将对螺旋桩和压浆螺旋桩的抗震性能进行研究。这项研究的结果将使桥梁工程师能够使用这些基础选择来支持加拿大地震活跃地区的桥梁和其他交通基础设施。此外，将采用基于机器学习的方法分析桩基桥梁的地震反应。这将有助于量化受损桥梁的震中损伤和震后承载能力。这些结果可以帮助交通运输机构在地震发生后立即分配公众认知的损害标签（例如，绿色、黄色和红色标签分别代表全面运行、有限运行和关闭）。预计这项研究计划将有利于许多新的基础设施项目和评估现有基础设施的地震脆弱性。

Recent earthquakes have witnessed severe damage to bridges and buried structures due to ground motion, soil liquefaction and associated lateral spreading. The new 2020 National Building Code of Canada stipulates substantially increased seismic hazard across most major Canadian cities. In particular, British Columbia and the Quebec City-Montreal-Ottawa corridor are seismically active. Thus, the sustainability and resilience of the built environment have become increasingly important and of concern. Integrity of critical infrastructure relies substantially on the performance of their foundations. The proposed research program aims to develop sustainable and resilient deep foundations and buried structures for infrastructure projects, which will withstand environmental hazards and will save resources. This research will develop, test and analyze resilient and sustainable foundations and buried structures for highway and road infrastructure and will evaluate the seismic performance of different deep foundations and buried structures. The research will be accomplished using novel shake table testing and the state-of-the-art newly-established Western Geotechnical Centrifuge. In addition, full scale testing of innovative pile options and guidelines will be developed for their design. In particular, this research will investigate developing innovative grouted helical piles that can provide efficient and resilient foundation option for bridge infrastructure, and investigate an efficient precast three-sided reinforced concrete (TSRC) culverts for road and highway infrastructure and develop specific guidelines for their design. This is particularly important as the current practice used for design as specified in Canadian Highway Bridge Design Code (CHBDC) treats TSRC culverts same as the conventional box culverts, which results in overly conservative and expensive design. The developed design guidelines will be submitted to the relevant CHBDC committee for consideration of incorporating them in the next version of the code. The research will also investigate the seismic performance of helical piles and pressure grouted helical piles. The findings from this study will allow bridge engineers to use these foundation options to support bridges and other transportation infrastructure in seismic active regions across Canada. In addition, the seismic response of pile-supported bridges will be analyzed using machine learning-based approach. This will lead to quantifying the in-earthquake damage and post-earthquake carrying capacity of damaged bridges for operations. These results can assist transport agencies to assign damage tags immediately after the earthquake for public cognition (e.g., green, yellow and red tags for full operation, limited operation, and close, respectively). It is anticipated that this research program will benefit many new infrastructure projects and assessing the seismic vulnerability of existing ones.