Extradosed Bridges for Major River on Vadodara Mumbai Expressway

National Highways Authority of India (NHAI) proposes to construct about 400 km long Mumbai- Vadodara (VM) Expressway to be implemented under Public Private Partnership. This is part of 1000 kms of expressway being developed under National Highways Development Program (NHDP) Phase-IV. The Authority has commissioned the services of M/s. Intercontinental Consultants and Technocrats Private Limited (ICT) for carrying out consultancy services for “Preparation of Feasibility cum Preliminary Design Report for the Expressway.

For the particular sites of Ulhas River (near Mumbai) and Tapi River (near Surat) under proposed Vadodara-Mumbai Expressway Project, there is a navigational requirement of minimum 100m horizontal clearance and 10m vertical clearance above HFL / HTL through the bridges. Ulhas river crossing is close to the Arabian sea, while Tapi river crossing is in the open. Both the crossings are near urban setting, Ulhas being close to Mumbai and Tapi being close to industrial city of Surat. From aesthetic considerations and from navigational requirement, extradosed bridges have been planned and designed as a part of Detailed Project Preparation for the Expressway.

This paper brings out justification for adopting extradosed type superstructure for the two river bridges on proposed Expressway. Main bridge on these river crossings is proposed as an extradosed span module of 75 m+120 m+120 m+120 m+75 m to be constructed with transversely pre-stressed single cell 21 m wide precast box segments of uniform depth of 3.5 m besides along with simply supported viaduct spans of 45m on either side of main bridge. The paper also brings out the design criteria adopted for the extradosed bridges along with a brief historical background and concept.