详情

原文传递 In-Situ Load Testing of Bridge A6358 (Part 1) and of Bridge A6101 and Bridge A6102 (Part 2).

题名：	In-Situ Load Testing of Bridge A6358 (Part 1) and of Bridge A6101 and Bridge A6102 (Part 2).
作者：	CASADEI, P.; GALATI, N.; NANNI, A.
关键词：	Bridge-monitoring; Load-tests.;Monitoring-; Bridge-decks; Concrete-structures; Structural-analysis; Fiber-optics; Steels-; Thermal-effects.
摘要：	This report presents the assessment of a High Performance Steel (HPS) bridge located at the Lake of the Ozarks in Miller County, MO. The bridge number is A6358 and it is located on US Rt. 54/Osage River. Two different modern techniques for Structural Health Monitoring (SHM) were applied for this purpose, in order to advance their field validation process. Displacements of the girders during the pouring of the concrete deck and a diagnostic load test, conducted after the bridge completion, were evaluated using an optical non-contact measurement technique based on an automated total station system. The setup included a total of 22 reflecting prisms mounted onto the bottom flange of the girders, plus four reference targets placed outside the bridge superstructure. Strain and temperature distributions along some of the girders were measured during the diagnostic load test using a fiber optic distributed Brillouin sensing technique. The method is based on the Brillouin phenomenon, which defines a linear relation between the axial strain in an optical fiber, and the corresponding shift in the frequency distribution of the scattered Brillouin light generated when an optical impulse runs through a fiber. A single optical circuit, comprised of bare fibers and a custom-made novel glass FRP tape with embedded sensing fibers, was installed on the web of the girders at different depths, along two continuous spans. Experimental deflection and strain data were verified to be consistent with each other and allowed to evaluate the actual girder distribution factors. The comparison between experimental and theoretical results based on the AASHTO LRFD Bridge Design Specifications (AASHTO, 1998) allowed establishing the safety of the structure, although pointing out a significant drop in the expected behavior of one of the external girders, which may call for further assessment.
报告类型：	科技报告