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Case study: Widening an existing bridge structure Challenges and solutions

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This paper is a study that summarizes, the procedure used to increase the capacity of an existing concrete bridge in the UAE. Traffic congestion is a severe problem in modern life. Severe congestion can negatively impact the country's economy, environment, and the health of road commuters. The increase in trip duration due to traffic congestion will result in consuming more fuel which results in a higher cost of trip and more emissions which affect both the economy and the environment. Moreover, the road commuter will be traveling for a long time which can affect their sleeping hours and mental health. Constructing more roads, and bridges and encouraging people to use public transport are some of the measures taken to reduce traffic congestion. To evaluate the effectiveness of an existing highway, certain parameters such as traffic quantity, type of vehicles in the traffic stream, speed of traffic stream, and the density of traffic stream will be measured and assessed to determine the need for increasing the road capacity. This paper considers the structural part and challenges faced during the process of widening an existing bridge structure. The existing bridge under consideration is composed of two spans with a length of 33.10 m of each span, two abutments with pot bearing connection, a single monolithic pier, asphaltic plug expansion joint at abutments, voided post-tensioned concrete slab with concrete barriers. The decision was taken to widen the existing bridge to relieve the aggravated traffic jam problem. The development of residential areas nearby resulted in increasing the volume of traffic exceeding the existing road capacity. The new development proposal involves the construction of a completely new bridge with 4 lanes and the widening of the existing bridge. The final output is two bridges with 4 lanes in each direction

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https://www.researchgate.net/publication/377951645_Case_study_Widening_an_existing_bridge_structure_Challenges_and_solutions




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