Temporary propping of deep excavations - guidance on design

Demand is rising for buildings with more basement space, highway underpasses and rapid transit lines, all of which require excavation propping systems. Different methods for calculating prop loads have led to significant variation in these temporary works. There is a need for clear and authoritative guidance on the practical limits to which ground movements can be restricted. This book provides guidance on the design of temporary propping systems for deep excavations with the aim at improving efficiency in their use while ensuring safety. It proposes a new empirical method for establishing temporary prop loads for design, developed from the Peck approach and based on a comprehensive survey of field measurements of prop loads. Distributed prop load diagrams, derived from analyses of the measured loads, are provided, from which prop loads may be obtained. The application of this distributed prop load method is explained, illustrated by worked examples.