A new basement has to be excavated in a confined city centre site surrounded by main roads...

To minimise the depth of 'cofferdam' piles a high level prop is useful. If the site is small and easily bridged, this is not a significant problem. If the site is large, a heavy duty alternative is required. This could be structural steelwork designed for this job only but using standard components for a short term contract can be much more economical.

Techniques

Using heavy duty props with load capacities of up to 1000 kN (100 tonne), erected in conjunction with steel soldiers to provide braced struts, E P Rothwell & Sons Ltd can design and erect propping to support all types of wall.
If special end fixings are required, these can be fabricated to suit in our own workshops.
Where necessary, foundations can be installed to support struts to carry the weight of props and enhance load carrying capacity.
All necessary timber and steel packing will be installed as a matter of course during the erection process.
Any holes or rebates required in the structure will be cut out and prepared to receive the propping and resin packs installed as necessary.
Any particular requirement for working in the excavation will be taken care of so that there is no need to worry about damage being caused when working through the temporary supports.
Work is undertaken by our own labour, all of whom have been trained in the handling of heavy equipment and working in all types of site environments. They are all experienced in this type of work and bring many years of their varied experience to bear on every job that they work on.
The team allocated to each job will be carefully selected and sized to suit the required rate of progress and will arrive on site with all of the materials necessary to carry out the work with the minimum of supervision by the client. All tools and equipment will arrive with the team including all of the little but important items that would take an age to assemble if you were to do it from scratch.

Case Study

During the enabling works to a new large building being erected over the main railway into Liverpool Street station in London, it was necessary to remove earth bunds which had been left to maintain stability of a secant piled wall. Megashor props were designed to accommodate the specified loading on the ground beams and transfer it through the main over rail structure. The total length of excavation was substantial.

To allow for future works the props were positioned at a level that enabled the skin walls to be cast complete, meaning that different end supports were needed in each location. The site welding was carried out by our own labour to ensure satisfactory installation of the props.
Where the span of the props was too great to carry the required load without intermediate support, pad foundations and vertical props were installed. These were positioned to avoid drainage and other services.

1)The shores were assembled on one side of the excavation and lifted in complete sections to minimise the use of cranes.

2) Cross bracing and slim soldiers combine to keep effective lengths to a minimum and maximise the load carrying capacity of the Megashors.

3) The end detail was designed to eliminate horizontal fixings into the structure and enable a rapid installation of the complete shores.

Basement Shoring Gallery