Development of serviceability limit state design criteria for stresses in prestressed concrete girders

Abstract

The objective of this paper is to perform the reliability analysis of stresses in prestressed concrete girders and development of design criteria for serviceability limit state design. Limit state functions for Serviceability Limit State (SLS) for compressive and tensile stresses at initial and service load stages are formulated based on fundamental design principles in the code. To establish statistical characteristics of concrete tension strength, two kinds of cylinder test, splitting tension tests and bending tension tests are performed for various specified strength of concrete. Other statistical characteristics for other variables such as live load, prestress forces, girder dimensions, and etc. are collected from related studies and references. Reliability indices are calculated for actually designed section and minimum section conformed with design requirement of typical prestressed concrete I-shaped girder and box type girder using first-order reliability method. Results are compared with reliability level of Ultimate Limit States (ULS) and target reliability indices of international standards. Finally, the live load factors in load combination for tensile stresses in prestressed concrete girder are proposed.

Reliability analysis of a prestressed bridge beam designed in serviceability limit state as recommended by NBR 6118 and 7188

“…Hwang, Nguyen and Nguyen [12] investigated the reliability indexes of bridge precast prestressed beams in SLS for the existing Korean traffic load model and a traffic load model recently proposed. The traffic load effect was assumed to be lognormally distributed.…”

Permit checking of overloaded customized transport vehicle based on serviceability limit state reliability of concrete bridges

“…With the continuous progress in the researches of material science and meanwhile the accumulation of field test data, more and more statistical information is applicable for the reliability analysis (Val and Chernin, 2009). For example, the detailed statistical properties of random variables used to calculate the deformation, concrete stress and crack width were provided in the research of Honfi et al (2012)Hwang et al (2014) and Li et al (2005) respectively.…”

“…The greatest advantage of reliability theory in structural assessment is that it can provide a universe target performance level for all assessment cases (Ghasemi and Nowak, 2017). To date, significant progress has been made in structural SLS reliability analysis, including the theoretical description of SLS, the determination of target reliability index and cognition towards the uncertainty embedded in the key variables (Bian et al, 2017; Hwang et al, 2014; Roubos et al, 2018; Quan and Gengwei, 2002; Stewart, 1996). These achievements make it possible to develop a SLS reliability based permit checking method of overloaded CTV through the optimization on critical load effect ratio.…”