The Kenyan Low Cost Modular Timber Bridge

At a glance..

This report assesses the design, suggests some minor modifications to the design, reports the results of loading tests performed on single frames, groups of frames, and complete bridges, and provides guidance on safe loadings and costs.

The details..

"The Kenyan Low Cost Modular Timber Bridge" by J.D. Parry presents an innovative and cost-effective solution for building bridges in rural areas with light commercial vehicle traffic. The book details a modular type of timber truss bridge designed by Mr J.E Collins under a project sponsored by UNIDO (United Nations Industrial Development Organisation). By early 1976, four such bridges had already been built in Kenya, and twelve more were planned.

The design fulfills its primary objective - providing relatively cheap bridges capable of carrying light commercial vehicles while also being quick and easy to erect or dismantle if needed. Similar to Bailey Bridges, basic units can be stored ready-to-use during emergencies or used interchangeably at various sites depending on their load-carrying capacity requirements.

Detailed loading tests performed on single frames, groups of frames, and complete bridges have indicated that this design is suitable for spans ranging between 12-24 meters while carrying limited numbers of vehicles up to 20 tons gross weight provided that the deck contributes significantly towards the structural strength. This assumption would not normally apply but measurements show otherwise; however evidence regarding durability under higher traffic loads remains unavailable.

In conclusion,"The Kenyan Low Cost Modular Timber Bridge" provides valuable insight into an affordable alternative approach towards building sturdy yet economical structures capable enough for moderate vehicular movement across rivers or other water bodies without compromising safety standards.