Using FRC and UHPFRC with conventional reinforcement for the seismic design and rehabilitation of bridge piers and for the design of bridge superstructure elements

使用 FRC 和 UHPFRC 与常规加固进行桥墩的抗震设计和修复以及桥梁上部结构元件的设计

基本信息

批准号：
RGPIN-2017-05699
负责人：
Massicotte, Bruno
金额：
$ 3.72万
依托单位：
École Polytechnique de Montréal
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2022
资助国家：
加拿大
起止时间：
2022-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754669
关键词：
Using FRC UHPFRC conventional reinforcement

项目摘要

Canada is one of the world industrialised countries where strategic infrastructures are subjected to the most severe climatic conditions. In Quebec, 35% of the ±10000 bridges still need to be rehabilitated for gravity loads and durability [1]. This rehabilitation process quickly becomes a never ending cycle due to the limited durability of repairs with conventional concrete. Knowledge gained in the past decades on the seismic hazard and on the deficiencies of several concrete structures demonstrated the vulnerability of structures built before 1980. This particularly affects bridges in densely populated regions of Canada. In fact, 80% of bridges in Quebec were built prior to modern seismic provisions, from which only a very few have been rehabilitated to conform to current seismic standards. This affects many lifeline and major-route bridges.Combining conventional reinforcements with fibre reinforced concrete (FRC) and ultra-high performance fibre reinforced concrete (UHPFRC) has been shown to be the most promising technical and economical solution for designing, rehabilitating and strengthening structural elements due to their exceptional structural performances and durability [12,13]. Although they are slowly but surely being introduced by some jurisdictions worldwide and in Canada in limited pilot projects, Canada's standards and industries are not yet prepared for implementing these innovative materials. Several issues still need to be addressed before sound and robust specifications become mandatory for the design and rehabilitation of concrete structures. This is the aim of this research proposal which focusses on developing knowledge, analytical tools, and design requirements to be implemented in the Canadian Bridge Code for using these innovative materials in structural applications based on rational principles.This application includes four projects that combine large scale testing on structural members, material testing, and nonlinear finite element analysis (NLFEA) for assessing the behaviour of structural elements at member or local levels. Two projects are related with the seismic rehabilitation and design of concrete bridge piers: 1) on the plastic hinge length and strain penetration in footings of large rectangular bridge piers, and 2) on the confining effect of UHPFRC active cover and reinforcement on column strength for seismic rehabilitation, or for accelerated bridge construction (ABC) projects. Two projects focus on developing design requirements for introducing FRC and UHPFRC in the Canadian Bridge Code: 3) on the bond strength of anchored and lapped reinforcing bars in UHPFRC and 4) one the development of a reliability framework for designing with FRC and UHPFRC. The project will be realised with a well-balanced group of HQPs: one senior research associate, one PDF, and 4 PhD, 8 MSc students and a minimum of 10 undergraduate students.

加拿大是世界工业化国家之一，战略基础设施处于最严重的气候条件。在魁北克，仍需要修复重力负荷和耐用性的±10,000座桥梁[1]。由于使用常规混凝土的维修耐用性有限，因此这种康复过程很快成为一个永无止境的周期。在过去的几十年中，知识对地震危害以及几种混凝土结构的不足证明了1980年之前建造的结构的脆弱性。这尤其影响加拿大贫困地区的桥梁。实际上，魁北克的80％的桥梁是在现代地震规定之前建造的，只有很少的人可以康复以符合当前的地震标准。这会影响许多生命线和主要的横向布里奇斯。通过纤维增强混凝土（FRC）和超高的性能纤维增强混凝土（UHPFRC）的传统增援已被证明是由于其出色的结构性和杜尔的效果和增强结构性元素而设计，修复和增强结构性元素的最佳证明技术和经济解决方案[12,13,13,3,13，3，1 13，13，13，13，13，13，13。尽管全世界的某些司法管辖区和加拿大在有限的试点项目中逐渐引入了它们，但加拿大的标准和行业尚未为实施这些创新的材料做好准备。在声音和强大规格成为混凝土结构的设计和康复之前，仍然需要解决一些问题。这是该研究建议的目的，它着重于开发知识，分析工具和设计要求，将在加拿大桥梁代码中实现，以根据理性原则在结构应用中使用这些创新材料。该应用程序包括四个项目，这些项目结合了结构成员，材料测试和非线性有限元分析（NLFEA）的大规模测试，以评估成员或本地一级的结构元素的行为。两个项目与混凝土桥墩的地震康复和设计有关：1）在塑料铰链长度和大型矩形桥墩的基础上的应变渗透以及2）关于UHPFRC主动覆盖和增强柱强度对地震康复的柱子强度的限制效应，或者用于加速桥梁构建（ABC）项目。两个项目着重于在加拿大桥梁代码中引入FRC和UHPFRC的设计要求：3）关于UHPFRC中的锚定和绑定加固条的键强度，以及4）一个开发了与FRC和UHPFRC一起设计的可靠性框架。该项目将通过一个均衡的HQP实现：一名高级研究助理，一名PDF和4位博士学位，8个MSC学生和至少10名本科生。