Innovative CFRP Prestressed Concrete Box-Beam Bridge System

预应力混凝土箱梁是美国中小跨径公路桥梁建设中最常用的结构构件之一。然而，这种类型的桥梁在各种状态下都遇到了严重的问题。这些问题包括：(1)钢筋锈蚀导致混凝土劣化；(2)箱梁之间的面板纵向裂缝；(3)面板纵向裂缝导致的渗漏问题。这些综合问题要求维修和恢复这种类型桥梁的承载能力的维护成本显著且不断增加。为了解决上述问题，需要开发、评估和实施一种新型碳纤维增强聚合物（CFRP）箱梁桥体系的创新设计和施工方法。此外，开发的方法必须考虑到箱梁桥的及时重建，以减轻对交通的干扰。这种开发和评估需要CFRP筋/箍筋制造商、预制件/承包商、学术界和最终用户之间的广泛合作。这项研究将在劳伦斯理工大学进行，由多元化复合材料公司、预应力系统公司（PSI）和密歇根交通部合作。在第一阶段，四个全尺寸箱梁，两个带PT筋的梁和两个不带PT筋的梁将在使用、疲劳和极限载荷下进行测试。第二阶段将解决两个桥梁模型在施工和服务的各个阶段的行为。拟议的RUI合作将扩展到两国本科生的教学和研讨会活动。玻璃钢生产商、预制工和MDOT工程师将成为LTU的客座讲师。大学本科生研究小组和工业合作伙伴将在美国联合总承包商（AGC）的年度会议和大湖DOTs联盟的会议上提供研讨会。大学与CFRP制造商/MDOT/CFRP预制商之间的合作将导致一种创新的腐蚀/免维护CFRP预应力混凝土箱梁桥系统的发展。

Prestressed concrete box-beams are one of the most commonly used structural components for the construction of small and medium span highway bridges in the United States. However, the problems experienced by this type of bridge in various states are serious. These problems include: (1) deterioration of concrete resulting from corrosion of steel reinforcements, (2) longitudinal cracks in the deck slabs between the box beams, and (3) leakage problems due to the deck slab longitudinal cracks. These combined problems mandate significant and continuously increasing maintenance costs to repair and restore the load carrying capacity of this type of bridge.To solve the above-listed problems, an innovative design and construction approach of a new and long lasting box-beam bridge system using carbon fiber reinforced polymer (CFRP) needs to be developed, evaluated, and implemented. In addition, the developed approach must allow for the timely reconstruction of box-beam bridges to alleviate the disruption to traffic. This development and evaluation will require extensive collaboration among: CFRP tendon/stirrup fabricators, precaster/contractors, academia, and end users. This study will be conducted at Lawrence Technological University with collaboration from Diversified Composites, Inc, Prestressed System, Inc. (PSI), and Michigan DOT.In the first phase, four full-scale box-beams, two beams with and two beams without PT tendons will be tested under service, fatigue, and ultimate loading. The second phase will address the behavior of two bridge models during various stages of construction and in service.The proposed RUI collaboration will be extended to teaching and seminar activities for our undergraduate students. The FRP producer, precaster, and MDOT engineers will be guest lecturers at LTU. The university undergraduate research team and the industrial partners will provide seminars at the annual meetings of the Associated General Contractors of America (AGC) and at meetings of the Great Lakes DOTs Consortium.Collaboration between university and CFRP-manufacturer/MDOT/CFRP-precaster will result in the development of an innovative corrosion/maintenance-free CFRP prestressed concrete box-beam bridge system.