Effects of Transverse Panel Strand Extensions on the Behavior of Precast Prestressed Panel Bridges

Abstract

O ne of the newer types of composite bridge construction, in common use today, involves the use of precast prestressed concrete panels which span between longitudinal girders and act as formwork and support for the cast-inplace deck (Fig. 1). This type of bridge has been studied previously,'6 and has generally performed well. Typically, 3 in. (76 mm) prestressing strand extensions project from the sides of the panels (Fig. 1). Elimination of the extensions would facilitate continuous bed manufacture of the panels. This study was undertaken to investigate the structural performance of panels without strand extensions. The study is described in detail in Ref. 7, and is summarized here. Scope and Objectives: A full scale bridge specimen was constructed and tested in the lahoratory_ The northern half of the specimen was made using panels with 3 in. (76 mm) transverse strand extensions, and the southern half, using panels without such extensions. In all other respects, the bridge was similar to actual bridges built for the Texas State Department of Highways and Public Transportation (Texas SDHPT). The specimen was tested under static, fatigue, and concentrated loadings. The primary objective was to determine if the absence of transverse panel strand extensions would affect the bridge's performance under fatigue and static loading conditions. Other objectives were to evaluate the response of the deck to concentrated loads, and to