Over the Indian River - Melbourne, FL

The Problem

The bridge located in Melbourne, Florida is one of two local access ways leading to beaches on the East Coast of Florida. The structure, built in the 1950’s, carries four lanes of vehicular traffic over the Indian River. The bridge consists of six 30 ft. long simple spans. Each span is composed of cast-in-place reinforced concrete rectangular beams with an 8?thick deck

The water of the Indian River is a combination of salt and brackish water. The first span of the bridge was built with only three feet clearance from the low tide water level. At high tide, the water level contacts the beams, creating one of the harshest environments for reinforced concrete structures. All beams in the first span showed signs of severe deterioration. Years of repeated exposure to wet-dry cycles left the beams and deck in critical condition. Inspection of the damage revealed loss of cross-section from concrete spalling, severe flexural and shears cracking and corrosion of reinforcement. In some beams, the bottom layer of the steel reinforcement had lost up to 90% of steel cross-section due to corrosion. Most of the structural damage was concentrated in this span.

An emergency situation was recognized due to the fact that the bridge is a critical access to and from the beaches and that the area relied heavily on income from the tourist industry. Replacement of the first span was considered to be the only option for rehabilitation. Closing the structure for an extended length of time to allow replacement of the span was considered costly and undesirable.

The MAS2000 Fiber Wrap System provided a viable option to costly conventional replacement. Utilizing this rehabilitation technique allowed rapid restoration of all girders to their original design strength.


Views of Corrosion Damage to Undersides of Concrete Beams and Deck Slab

The Solution

A non-linear finite element analysis of the existing conditions was conducted to evaluate the remaining strength of the girders. The results of the analysis were used to design the optimum rehabilitation plan.

Rehabilitation began by cleaning and chemically treating all corroded reinforcement. In many cases, additional concrete had to be removed from the cross-sections so that the full length of damaged steel could be exposed and treated.

All spalled and unsound concrete was removed prior to restoring the beam cross-sections to their original shape. The spalled concrete was replaced with a high strength concrete and formed to match the original shapes. Following the concrete cure, the surfaces were treated in preparation for receiving the carbon composite materials.

The girders received the MAS2000 Fiber Wrap System for lengths ranging from 12 to 20 ft,. fully covering the damaged regions. The rehabilitation was performed during normal daytime hours by a minimal work force. The application took approximately eight hours.

A waterproof coating was applied to the girders to provide additional protection against the damaging effects of salt-water spray.

The original appearance of the structure was restored and enhanced by painting the laminates with a specially designed ultraviolet (UV) resistant coating. The MAS2000 Fiber Wrap System proved to be economical, quick and easy to apply.

This structure was rehabilitated in 1993. It was one of the first bridges to ever receive such a technique and it has been performing well ever since.


Views of Rehabilitated Girders (Prior to Application of Final Finish Coat)