Fulham Palace Road Temporary Works Design

Beta Scope

• Visual inspection and general structural survey of the property and the collapsed gravity masonry retaining wall
• Evaluation of the hydrostatic and surcharge loading on the retaining wall in the normal wet condition and in the saturated condition
• Advising the insurance companies on the most likely cause of collapse
• Advising the client and the local authority on the repair method
• Preparation of a method statement and temporary works design
• Preparation of specifications for foam concrete and resin injection
• Preparation of construction transport management plan and swept path analysis
• Preparation of services plan to coordinate excavation around HV and LV cables, coordination with all utility suppliers including UKPN, BT, VIRGIN, Thames Water and Cadent Gas.

Background

Beta Design Consultants were commissioned by the Client to inspect a collapsed basement wall that retains soil under a busy high street and advise on required repairs and prepare the method statement and the temporary works design for the commercial property. The front property has basement lightwell and masonry retaining wall under the footpath. Footpath collapsed due to the failure of the retaining wall. It was believed that the failure of the retaining wall was due to increased lateral pressure believed to have been caused by the water leakage from the water mains pipe. The affected area lied in the highway vicinity which was a risk to the public. The collapsed section was temporarily barriered off with partial lane closure and the structure deemed dangerous by the council.For the contractor to carry out the repair works Beta Design Consultants were required to come up with a temporary works design and construction method approved by the Council.

Beta Solution

Beta Design Consultants proposed trial pits to establish the extent of soil erosion, to advise on the extent of the grout injection that would be necessary. They proposed working platform supported on the needle beams sitting on the new concrete beam inside kerb and Acrow props on the basement. Cast in-situ trough was designed to protect the services. The new gravity retaining wall created with foam concrete was proposed to be anchored to the soil using ground anchors so that new gravity wall will not transfer the load to the basement wall. DPM to be applied between basement wall and the compressive material so that retaining wall will not transfer any dampness to the basement wall.

Practical Details

Cast in-situ trough was designed for highway loading. Beta Design Consultants produced a detailed construction method statement and risk assessment to ensure works were carried out in a safe, practical and correct sequence.