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原文传递 Vulnerability Reduction for Bridge Piers. Final rept. 1 Jun 03-24 Aug 05.

题名：	Vulnerability Reduction for Bridge Piers. Final rept. 1 Jun 03-24 Aug 05.
作者：	FARHAT, N. S.; SERRANO-PEREZ, J. C.; UDDIN, N.; VAIDYA, U.
关键词：	Bridge-piers; Axial-loads; Strengthening-; Vulnerability-.;Dynamic-loads; Earthquake-engineering; Eccentricity-; Blast-loads; Heavy-trucks; Impacts-; Fiber-reinforced-composites; Concrete-reinforcement.
摘要：	Concrete bridge piers are designed to withstand large compressive axial loads but often fail under eccentric out-ofplane loads such as those created by an impact or explosion. In the wake of recent terrorist attacks, such loading is of increased concern. Retrofitting the piers with continuous-fiber-reinforced thermoplastic polymers could reduce vulnerability to these loads. Fiber-reinforced composites are relatively new materials that show great promise in concrete retrofit. Presently, fiber-reinforced thermoset polymers are used to add stiffness and tensile strength to concrete bridge members; however, there has been no effort to utilize the superior impact resistance of continuous fiber- reinforced thermoplastic polymers to protect bridge piers against out-of-plane loading. The overall objective of this research was to pioneer a new and promising technology to reduce the vulnerability of bridges to dynamic loads that deliver immense energy to the structure in a very short time, such as impacts from trailer trucks, blasts, or earthquake effects. Low-cost long-fiber thermoplastics are emerging as affordable technology for rapidly producing thick structures with integrated attachment points and features that can reinforce bridge structures for collision and impact loads. For the purpose of this study, samples were cast as 6 diameter x 24 cylinders, concrete prisms, small size concrete cylinders and concrete panels with a glass/polypropylene (PP) face sheet. These specimens were created to study various aspects of the processing, and behavior of the concrete and composite specimens. The cylinders were used to study the enhancement in compressive strength and ductility created by glass-fiber-reinforced PP reinforcing jackets. The prisms were used to determine the shear strength of the bond between the thermoplastic wrap and the concrete specimens through the in-plane shear test, and the strength of the bond through the pull-off test. The thin panels laminated with glass/PP were used to determine the impact resistance of a composite panel through projectile ballistic testing. A finite element numerical model was then created using LS-DYNA software to predict the results of the ballistic impact testing, thus establishing a baseline model for simulating the impact behavior of bridge piers.
报告类型：	科技报告