Comparative Structural Behavior of Straight & Skew Box Type Rail under Bridges

Abstract

Box structure is an extensively used structural element which usually carries uniformly distributed gravity loads along with lateral forces like earth pressure, breaking, tractive forces. These types of structure are most economical structure as compare to other type of structures like slab type minor bridges, Reinforced cement concrete or Prestressed cement concrete I girder with abutment, steel structures etc. Box type structures are also very efficient and good where the bearing capacity of soil is low. These types of structurers are the simplest among the other possible structure and contain top and bottom slab and side walls only. The nomenclature Of box structure varies from department to department and country to country but method of analysis and design is almost similar. For example as per Indian road congress nomenclature of boxes is done as per there span arrangement while in Indian railway, this is done on the bases of their usage. All structure used to cross a hydraulic structure comes under minor or major bridge type while structure use crossing are called as low height subway or rail under bridges.