الفهرس 
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Abstract
An approach slab serves as a transitional system between an approach road and a bridge. The primary function of the approach slab is to diminish the amount of differential settlement between a filled embankment and a bridge abutment. If the approach slab does not function properly, a driver will feel a bump while driving across a bridge abutment. An approach slab settlement resulting in a ”bump at the end of bridge” can lead to many negative effects on the function of roads, impacts on bridge and road structures, and subsequent increase in maintenance costs. Uncomfortable and unsafe driving conditions, road accidents, automobile damage, and damage to sensitive transported goods are a few detrimental of the effects relating to the function of roads. The road bump creates repeated and increased impact loads from the dynamic impact of vehicles to bridge and road structures; thus, reduces the lifetime of the structures. Recognizing the problems with current approach slab systems faced by transportation agencies, this paper identifies specific factors causing the settlement problems, provides practical recommendations to enhance the performance of approach slab systems, and suggests improvements to current design and construction practices.In general the main reasons of approach slab settlement (bump) and failure is according to: Poor compactive effort of embankment fill and not anticipating settlement of foundation soil. Poor drainage leading to fill washout and development of voids under approach pavements.Poor joint development leading to abutment displacement via pavement growth, and not correctly accounting for temperature cycles.