Richmond Steel Bridge Construction

The following key elements formed part of the project scope:

• Construction of a 25 m clear-span steel bridge with sufficient freeboard above the 1:50-year flood level.

• Reinforced concrete abutments designed to TMH 7 Part 1 & 2 specifications.

• Adjustment of the vertical alignment of the existing district road to suit the new bridge level.

• Embankment works and erosion protection measures.

• Demolition and removal of the existing damaged bridge structure.

Western side of the river:
Competent rock horizon was encountered at approximately 3 m below natural ground level (NGL). Test pits revealed very soft rock anorthosite with an in-situ bearing pressure of 300 kPa.

Eastern side of the river:
An alluvial layer consisting of cobbles, boulders, and silty coarse sand was identified. The saturated horizon caused significant washout and sidewall collapse during excavation, with an in-situ bearing pressure of 150 kPa. Very soft rock anorthosite was encountered only between 5 m and 8 m below NGL.

Based on the geotechnical findings, piled foundations were recommended for both abutments. This solution ensures stability and provides a reliable founding for the steel bridge structure.

The project is scheduled for completion within 7 months, from July 2025 to February 2026.

A total of 25 personnel were involved in the project, including permanent staff and contractors.

• 410 m³ of concrete

• 47 tonnes of structural steel