Roads and Pavement
engineering
Pavement Design
The key objective of Pavement Design is to ensure a serviceability lifetime of traveling surfaces subjected to vehicular traffic, e.g., roads, to the requirements of relevant SANS codes. The design includes a defined number of layer works with specific conditions, including but not limited to a subgrade, subbase, base, and surfacing, and is designed according to a number of million standard axles (80kN) that is expected to travel on the road. Pavement design ranges from public and private asphalt roads, to courtyard paving and paved roads. Furthermore, when a road begins to deteriorate, pavement design enables the determination of modes of failure and the extent to which repairs are required. The scope of services includes general assessment of client requirements, general assessment of site conditions, testing of in-situ materials on site, design of pavement layers according to Site specific data, and detailing and specification of layer works. Deliverables include details of layer works for construction.
Geometric Design
The services pertaining to Geometric Design of Roads are normally conducted in two stages – Preliminary Design and Detail Design. The Scope of Services offered includes route alignment and/or assessment of road reserve, function, and capacity requirements; detail Topographical Survey of the terrain; horizontal (plan) design including curve radia to match design speed, intersection spacing, and sight distance at intersections; vertical design; long and cross-sectional design; and quantities of cut and fill material (see Pavement Design for road layers).
Access Management
This service aims to propose access to existing and proposed roadways that balances access needs with mobility requirements within the context of functional classification. Studies include selective services as listed under Traffic Impact Studies. In the case of urban roadways, results often include the closing and/or relocation of access intersections, changes to the type of access control, and geometric upgrading. In residential neighbourhoods, the implementation of Access Control for Security Services provides the opportunity to effectively introduce Access Management in these neighbourhoods (Local Area Traffic Management).
Traffic Calming
This service focuses on the reduction of speed and improvement of safety, specifically on roads in activity areas. The Scope of Services offered includes assessment of the circumstances and quantification of the problem by means of speed surveys and/or accident statistics; evaluation of the road environment; assessment and selection of traffic calming measures most suitable to address the problem effectively; design and costing of the proposed; application for Municipal Approval; and assistance with implementation.