Retaining Walls

Includes temporary retaining walls such as sheet piles as well as single story basements, drainage chambers, service ducts, roadworks, cuttings, earthworks, watercourses etc.

Introduction

In designing retaining walls the designer should be aware of, and assess the risks from, the following principal hazards.

Some hazards and risks

• falls from height into excavation, from walls etc.
• hazards from services such as electricity, gas pipes etc.
• hazards caused by falling objects or substances such as unretained material, unstable wall, objects falling into excavation
• health hazards such as noise and vibration, dust, manual handling and water borne diseases
• hazards of work adjacent to water courses, roads or railways
• hazards associated with possible ground movement such as the subsidence of adjacent buildings causing fractures to services and waste pipes

Considerations

Investigate the implications of the location of the site such as adjacent buildings, roads, rivers and local services. Consider the construction sequences necessary, access for necessary plant and machinery and any required access to rear of the wall.

Some possible design options to reduce hazards

• consider the best type of wall for its position and use and its interaction with existing services such as gas or electricity
• evaluate the possible effects of the operation on adjacent structures
• identify any ground and surface water controls necessary
• design to minimise depth of excavations
• eliminate the need for confined space access to the rear of wall
• design wall to include facilities for ease of maintenance
• investigate possibility of services diversion during construction of the wall