Environmentally Induced Behavior of the Superstructure of Highly Skewed Bridges

Aim: This study critically examines the environmentally induced behavior of highly skewed bridge superstructures, a structural vulnerability that has been dangerously under-addressed relative to its consequences. Particular emphasis is placed on how temperature variation, thermal gradients, seasonal thermal cycling, and differential solar exposure combine to threaten the structural response, serviceability, and long-term survivability of skewed bridges. Study Design: The review adopts a comprehensive, critically focused analytical and literature-based approach, concentrating on studies published between 2021 and 2026 that address skew bridge mechanics, thermal loading effects, finite element modeling, and the deteriorating durability of bridge systems under sustained environmental attack. Methodology: The study was conducted through a systematic review of scholarly publications obtained from databases such as Google Scholar, Scopus, ScienceDirect, and Environmental Science& Policy. Relevant peer-reviewed articles relating to thermal behavior, structural deformation, support restraint effects, and environmental loading in skewed bridges were critically examined. Results: Findings from the reviewed studies indicate that environmental loading significantly influences the structural behavior of highly skewed bridge superstructures. Increasing skew angle was found to amplify thermally induced displacements, girder rotations, restraint forces, and support reactions, especially near acute and obtuse corners of the deck. Bridges with skew angles greater than approximately 45° exhibited pronounced three-dimensional deformation patterns that conventional simplified design approaches often fail to predict accurately. Differential solar heating and thermal gradients were also identified as major contributors to bearing distress, expansion joint deterioration, and uneven load transfer within the bridge system. Conclusions: Environmental effects play a critical role in the structural performance and serviceability of highly skewed bridges. Existing simplified design assumptions are increasingly inadequate for bridges with large skew angles under realistic environmental conditions. Improved analytical modelling, realistic thermal assessment procedures, structural health monitoring, climate-informed design, and enhanced detailing of bearings, expansion joints, and restraint systems are recommended to improve the long-term durability and resilience of highly skewed bridge infrastructure.