Design standards for road development and improvement schemes
This resource provides an overview of the design standards an engineer should use for road development and improvement schemes. It is an ICE briefing note that originally appeared as Road development and improvement schemes: highway design standards, written by Adam Kirkup and published on 31 March 2016
 Effective highway design and engineering
Good and effective highway design is based on an accurate knowledge of the properties of the materials used and the design loadings, using well-researched engineering principles and developed and validated computer programs. It must also take account of the interaction with the existing ground and the environment.
ICE’s Manual of Highway Design & Management (2011) provide descriptions of and notes for guidance to the referenced established design procedures and methods used in the UK and in some cases provides enough information for straightforward designs to be produced for that topic:
- Chapter 31 - Highway design principles and practice: an introduction
- Chapter 32 - Site investigation and foundation design
- Chapter 33 - Geometric design
- Chapter 34 - Drainage design
All highway design for Highways England must be carried out by consultants with BS EN ISO9001: Quality Management Systems. Requirements (British Standards Institution, 2008) third-party certification satisfying the requirements of their guidance document GD 02/08 Quality management systems for highway design published in Design manual for roads and bridges (DMRB). This explains how the general quality assessment principles are relevant to highway design, the management responsibility and which quality plans and records should be kept. It also explains the competency requirements for the design team in terms of skills, knowledge and ability to understand requirements.
 Specification for Highway Works
The Specification for Highway Works is published as Volume 1 of the Manual of Contract Documents for Highway Works and contains the requirements and approvals procedures for work, goods or materials used in the construction, improvement or maintenance of the Trunk Road network. This an essential reference tool for agents, authorities, consultants and organisations who are engaged in the design, assessment, maintenance and management of road and bridge design.
 Concept design and feasibility
In preparing a concept design for a major development, the highway engineer should address the practicalities of cost effective access for all modes of travel, assessment of the suitability of the existing infrastructure, the parking and servicing arrangements and the detailed design of on and off-site civil engineering works.
Feasibility studies involve both a desktop and a site visit, address the key fundamentals of access, and access constraints. Investigations will also take place to establish the current lawful use of the site and its present potential for generating traffic.
 Preliminary design
The purpose of the preliminary design is to enable a decision to be made about where the road should be located within the preferred route envelope. This design will include topographical, environmental and geographical surveys.
 Final design
The purpose of the final design is to:
- Produce further detailed topographical, geological and geotechnical surveys.
- Produce detailed design of bridges/structures, drainage, earthworks and pavement.
- Consider health and safety and factor this into the detailed design.
 Closing remarks and recommended resources
 ICE Books
The intention of this information is to give a general overview of highway design and direct engineers to further guidance and resources to help them in preparing highway design documents. ICE’s Manual of Highway Design & Management (2011) is an excellent resource for engineers of all levels, and is a highly recommended resource.
Equally useful is ICE’s Principles of Pavement Engineering (2014) and for the undergraduate engineer, Highways: the location, design, construction and maintenance of road pavements (2015) is an extremely useful reference tool.
 ICE Training
- Highway Design and Detailing using the DMRB
- Pavement Design Using the DMRB
- Specifying and using asphalts in roads and other paved areas with confidence
- Eurocodes courses
 External resources
- The Design Manual for Roads and Bridges (DMRB). This contains information about current standards, advice notes and other published documents relating to the design, assessment and operation of trunk roads, including motorways. The DMRB was introduced in 1992 in England and Wales, and following that in Scotland and Northern Ireland. Some standards and specifications have annexes specific to each devolved administration. You should contact the relevant devolved authority directly for guidance.
- Well Maintained Highways - Code of Practice. Published in July 2005, this provides local authorities with guidance on highways management in an ever-changing environment, creating a strong foundation for a positive and lasting maintenance policy. Adoption of the recommendations in this code will help the delivery of best value services.
- The Manual of Contract Documents for Highway Works. This contains the primary documents required for the preparation of contracts for trunk road works. It includes administrative procedures for its use, the specification for highway works and the corresponding method measurements.
- Interim Advice Notes. IANs issued by Highways England contain specific guidance, which should only be used in connection with works on motorways and trunk roads in England, subject to any specific implementation instructions contained within an IAN. IANs are not part of the DMRB and the MCHW but must be read in conjunction. They may incorporate amendments or additions to documents in these manuals.
- Eurocodes. As a public body, Highways England expresses its requirements for the design and modification of existing structures (including geotechnical works) in terms of Eurocodes. Highways England’s technical experts were involved in the drafting of the Eurocodes and the National Annexes.
- The Network Management Manual. The NMM provides mandatory requirements, guidance and advice for the management of maintenance of the trunk road network.
- Routine and Winter Service Code. This includes performance requirements for routine and winter service activities on the trunk road network.
- Traffic Management and Maintenance Manual. Published in January 2013, this sets out requirements for the management and maintenance of traffic technology systems.
 Related articles on Designing Buildings Wiki
- Hounslow highways pathfinder private finance initiative case study. March 2016.
- Highway drainage.
- Highways Infrastructure Asset Management Plans. October 2015.
- PAS 2080 Carbon management in Infrastructure. March 2016.
- Improving visibility and resilience of buried services. October 2015.
- Road construction.
- Road improvement scheme consultation.
- Road joints.
- Road traffic management.
- Types of road and street.
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