CIRIA begins work on ground movement impact guidance

CIRIA associate director Kieran Tully said, “We agreed that one of the critical success factors of the guide will be, over time, to change the mind-set of those specifying movement criteria […] the starting point for design can often be zero permissible movement without due consideration of the form of construction or the construction methodology.”

The guidance also aims to cover permissible movement for different structure types dependent on their condition and structural characteristics. Newer forms of structure will be given consideration. The nature of modern structures means that impact criteria needs reviewing.

The project’s key objectives are to:

• Identify common sources of ground movement and their methods of prediction using empirical and analytical methods.
• Provide guidance on permissible movement for different structure types and building systems dependent on their condition and structural characteristics.
• Show how current monitoring systems can provide information to maintain effective movement control.
• Include a number of case studies to show good practice implemented successfully.
• Outline the benefits of using good practice procedures.
• Engage with professional bodies, developers, local authorities, insurance organisations, buildings and infrastructure managers, façade engineers, tier 1 and 2 contractors, architects and designers and those with a role in managing construction impact from ground movement i.e. a multi-disciplinary approach.

Tully added, “It’s not just about the calculated figure, it is about the process to get to that figure. Is the calculation the right approach and has it been done by a competent person? Also, what criteria are being applied; is it just building movement or is it a holistic approach to serviceability? And it is about designing for a range of movement.”

The BTS is co-funding the project and Kelvin Higgins of the Geotechnical Consulting Group (and current British Geotechnical Association chair) is chairing the project steering group. The CIRIA guidance will help steer future guidance being prepared by the BTS.

The final aim of the project is to enable those with a role in managing construction impact from ground movement to better understand the impact and good practice management strategies.