Adaptable and flexible, Slimshore Soldiers are quick and effective when Propping and Needling is required during construction. Here’s all you need to know.
Posted 7 February 2024 by The SEL Team
Used as a means of support for a structure during construction works, propping and needling systems are a form of temporary works intended to maintain building safety by avoiding the collapse of walls and ceilings during alterations of an existing structure.
For instance, this kind of equipment is often used on a construction site when creating an opening in a load-bearing wall.
An adaptable and flexible system, propping and needling is quick and easy to deploy in most cases and can be used in both residential and commercial properties – and in all manner of challenging buildings. To give some examples, this method has been used when working with stone, old timber frames and even traditional cobb-style walls.
Spotlight on Slimshore
Formwork soldiers have proven to be an effective system for Propping and Needling and come in a range of sizes. A modular propping system with a variety of uses, Slimshore’s soldier units are a useful means of facilitating temporary support of structural walls in construction projects using conventional propping and needling techniques.
Slimshore soldiers can be used for a range of purposes, such as prop units (including HD push-pull props and HD props), raking shores and needle beams – making them extremely versatile on site and adaptable to meet a project’s needs at short notice.
Using a 4no. or 6 no. M16x40 bolted joint, soldiers can be connected end-to-end, making their deployment quick and easy. This modular approach also makes the kit is easy to transport.
When used as needle beams, Slimshore soldiers may be laterally restrained using light or heavy duty raking props to ensure stability, depending on the loading criteria.
Safety in mind
The design of Slimshore soldiers offers impressive weight to strength ratio. Their high load capacity, together with robust design, helps to ensure the safety of your team while using the soldiers as part of a propping and needling approach.
Securing the soldiers to a concrete base using anchor bolts offers an additional layer of safety.
The right accessories
A range of accessories are available to enable deployment of the soldiers in a variety of settings.
Other equipment used together with the Slimshore soldier units for propping and needling include Push Pull Props and Acrow Props.
Designed to take loads in both compression and tension, Push Pull Props come in a range of sizes, with load capacities from 35kN to 10kN, depending on length. Sometimes known as rakers, these props can be used with propping and needling equipment to temporarily support structural walls.
Push Pull Props can be used with the SEL Slimshore Soldiers by adding a ‘T’ Connector to the top plate and fixing the solider.
Also referred to as adjustable props, Acrow Props are used throughout the construction industry to provide temporary support for applications such as propping and needling. Site Equipment Ltd’s floor-to-sofit support system with fixing holes will keep the prop in the position required, with supplementary scaffold tube and fittings available if needed.
An adaptable and flexible system, propping and needling can save existing structures and give them a new lease of life.
The Acrow Props are available in five different sizes, with open heights ranging from 1.07m through to 4.87m. The maximum capacity is 3.5T with a capacity of 1.8T at 3m in length.
Key components
In addition to the Slimshore Soldier units, an adjustable base jack allows for fine adjustment in height, while left or right-handed jacks connect to the soldiers for heavy duty push pull props and the spade end link connects to the left and right-handed jacks to enable connection to the web hole in the soldier unit using the prop pivot tube.
Ancillary components include a U-Head which fixes adjustable props using 2no Countersunk M12x40 bolts to support a 180mm wide beam, along with a tilt plate used to connect heavy duty push pull props to a concrete base and a prop pivot tube, which secures the spade end link into the web hole of a soldier.
Propping and needling at Cordwell’s development for BoxHall
A great example of a propping and needling project at work is the execution of a recent project for Cordwell Leisure’s development for Bristol’s BoxHall, a new BoxPark concept coming to the O&M Sheds at the city’s Welsh Back.
Cordwell Leisure has meticulously rebuilt and renovated two of the last remaining 19th and 20th Century transit sheds known as O & M Sheds on the floating harbour.
Occupying a prominent location at the corner of Redcliffe Bridge and Welshback, the buildings provide wonderful vistas along the waterside and across to St Mary’s Redcliffe Parish Church and the iconic colourful villas of Redcliffe Parade opposite with the opening up of new picture windows and the creation of a feature harbourside terrace.
Cordwell has let the building to BoxPark which will open its first out-of-London new concept, BoxHall, based on a similar concept to its successful BoxPark venues. BoxHall Bristol has been described as a food, music and drink hall, set in two adjoining historic dockside sheds – offering 20,000 sq ft multi-use space and taking advantage of Cordwell’s newly created space providing a light, open feel with an industrial setting that reflects the building’s heritage.
Adding new doorways and windows
Cordwell’s renovation, working with Site Equipment Ltd and its main contractor, JH Group of Bristol, opened up to allow passage between the internal floorspaces, providing a continuous flow between the two sheds. Instead of utilising two former openings that had since been bricked up, the plans called for new doorways of around 3-4m in width on either side of those openings.
This was a relatively complex propping and needling operation, as it wasn’t possible to fit any propping on the ground and it was vital to create enough space to dig a trench underneath and add foundations. A ‘picture frame’ structure was instead created with a bottom member encased in concrete. To allow the excavation to be undertaken without undermining the temporary structure, Site Equipment Ltd developed a trussed structural support system on one side of the proposed opening to ensure that the supports were outside of the influence zone of the required excavations.
On the other side of the proposed opening, the propping was placed a suitable distance away from the work to prevent the propping from being founded within the influence zone of the proposed foundation excavation.
A challenging refurbishment
Changes in the construction programme required Site Equipment Ltd to provide temporary propping to a new roof structure to allow enhanced foundations to be installed along the side walls. It was also used to support the roof while new waterfront-facing windows were added.
However, the most ambitious element of the project was the formation of a 14m long opening in the end gable of the site to link the internal space with the external riverside and Redcliffe Parade Villas and terrace areas opposite. This side of the building has a prominent position, next to Redcliffe Bridge, which typically sees a lot of footfall. As well as creating the new opening, Cordwell was keen to tidy this up and restore the end gable to its historic roots with ornate brickwork that reflects its original design.
To form the opening, propping was required to support up to 8T per metre of masonry and roof loads being retained above the proposed opening. In addition to supporting these vertical loads, the system was required to sustain significant potential lateral forces.
The wall here was built with a thickness of around 450mm, but was reinforced to around 600mm in thickness at the time it was refaced, which meant there was a heavy load to support during this latest reconstruction. Plus, the length of the proposed opening required significant propping together with 13 lateral needles.
One of the biggest challenges was the presence of a large electricity substation close to the end gable, which had an impact on where the opening/propping could be located. As well as prioritising site safety at all times, careful planning was essential to avoid any disruptions to local power supply. This required a complex temporary foundation arrangement and offsets between the supported wall and available temporary foundation locations called for an innovative propping solution.
The size of the proposed openings meant that significant structural steel was required to support the masonry above. This further complicated the internal support arrangement to ensure that adequate space was provided to allow the new steelwork to be safely lifted into place.
The propping solution allowed the impressive openings to be formed safely, ensuring that the facing brickwork and associated finishes were in keeping with a building of this nature to protect its heritage.
Cordwell’s new lease of life for the building
Reclaimed brickwork was used to revitalise the appearance of the end gable and the steel used for the reconstruction will remain exposed to add to and protect the industrial feel of the building. This meant the needling work had to be carried out very carefully as there was no means of hiding any trace of it following removal.
The end result of the project is a strong example of how propping and needling can save existing structures and give them a new lease of life.
Site investigation
To ensure the most appropriate propping and needling measures are in place, a site investigation will recommend which equipment and materials are most suitable to provide temporary supports in any particular scenario, taking into consideration factors such as whether correct foundations are in place and the bearing capacity of supported masonry. For example, the condition of the masonry you’re working with can have an impact on the spacing between needles when arranging propping and needling solutions.
Our team of professional, experienced and qualified Civil and Structural Engineers are on hand to carry out site visits and extend their knowledge and advice on temporary works design.To find out more, including answers to any technical enquiries on propping and needling equipment, contact your nearest depot.