4. Bearing Capacity Design

This chapter will present different methods used in bearing capacity design of gravel roads and forest roads. This is one of the issues where design principles may vary substantially between public gravel roads and forest roads. For this reason some principles will presented separately. This chapter will also compare design principles used in different ROADEX partner countries and compare these in places to design principles in warm countries such as Australia (ARRB design guidelines).

4.1. Basic principles

Introduction of design principles of public gravel and forest roads. Presenting road classification, target bearing capacity, timber haulage amount, loading, haulage timing, spring thaw restrictions, subgrade class and road material types. comparisons between different ROADEX partner countries

4.2. Bearing capacity design of new road and renovation methods

4.2.1 Road class, loading and target bearing capacity

Description of different methods on how to define target bearing capacity of a gravel road.

4.2.2. Subgrade type

Description how to define subgrade type and use this information in bearing capacity design.

4.2.3. Materials

Grading specifications, moduli values and thickness specifications for different pavement structure materials, comparisons between different ROADEX partner countries

4.2.4. Design tables

Examples on how to use different tables in gravel road or forest road design, comparisons between different ROADEX partner countries

4.2.5. Odemark method

Description of ROADEX Odemark method and bearing capacity analysis and renovation design in gravel and forest roads. Examples of earlier ROADEX pilots from Sweden will be given.