Keywords: transverse crack, deck, shrinkage, deflection limit, creep, overlay.

Many parameters can affect the development of transverse cracking in bridge decks. The cracks can be influenced by material characteristics, formwork, climate conditions, geometry, load patterns, amount of deflection, and time dependent factors. Bridges and especially bridge decks experience problems of transverse cracking, which may lead to deterioration of bridges. The causes of early age cracking are mainly to the result of plastic shrinkage, temperature effects, autogenous shrinkage, and drying shrinkage. It is important to resolve the issue of transverse deck cracking otherwise several bridge decks may experience loss of stiffness and possibily loss of function which may affect the safety of bridges. This research study examines the effect of wide range of parameters on the development of cracking. The parameters include, the number of spans, span length, girder spacing, deck thickness, concrete compressive strength, dead load, hydration, temperature, shrinkage, and creep. The importance of each parameter is identified and then evaluated. Also, the AASHTO Standard Specification limits live-load deflections to L/800 for ordinary bridges and L/1000 for bridges in urban areas that are subject to pedestrian use. One of the main objectives of the study is also to ensure that the current deflection limit is adequate. Analytical models of bridges were developed to study the effect of wide range of parameters and a set of recommendations to limit the transverse deck cracks in bridge decks is also presented. This paper presents a number of outcomes. Spacing between girders was found to be an important parameter. When the spacing between girders becomes larger than the width of truck, the stresses developed increased significantly. The type of abutment can play an important rule to control the development of cracks. The use of monolithic abutments may lead to more cracking. The concrete compressive strength has an important contribution. It is recommended that moderate concrete compressive strength be used for bridge decks. The stiffness of the bridge deck is also imperative and affects the behaviour. Increasing the deck thickness lowers the stress produced. It is determined that the deflection limit is an important parameter that affects cracking. The current deflection limit needs to be revisited and modified.

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