Videos and animations

Videos and animations - Preamble

This page provides hyperlinks to videos and animations relating to temporary works topics.

NOTE
By providing links the Temporary Works Forum (TWf) does not provide or infer endorsement.

Bridge Construction

These hyperlinks provide examples of bridge copnstruction involving significant temporary works:

Pre-cast Slabs Form Viaduct Deck

Over 500 pre-cast concrete slabs were chosen to form the deck of a multi-span viaduct; comprising 17 spans (measuring 41 metres on the approaches and 59m over the water).  The first panel weighed 22.5 tonnes and was fabricated at the contractor’s near-by pre-cast yard.  The total crossing length was 747m and will carry six lanes of traffic over a flood plain and river. The pre-cast deck solution will save £4 million and two months in construction time, compared to an in-situ build. It was considered a much safer process and will result in a higher quality finish. It was a great example of constructability, innovation and safety in action.


Bridge Deck Roll-in

Two bridge decks were installed eighteen hours ahead of programme, using self-propelled mobile transporters (SPMTs). The many challenges were mitigated successfully through collaboration between the permanent works designers and the temporary works designers, including amending the design of the bridges to accommodate the temporary support configuration of the SPMT which differed from those of the permanent structure, and with the supply chain in the manufacture and delivery of the structures. Under a full closure, the team prepared the road surface throughout the night and into the early hours of the next morning, when the 44-metre bridge decks were guided into place using the huge remote-controlled platforms. The weekend’s success was a consequence of months of planning, thought and thorough preparation. The work finished so early because each member of the team did what they promised to do and, in many cases, exceeded expectations. There was excellent planning and execution.


Installation of Bridge Deck
A pre-fabricated bridge deck was guided by remote control along 4.6 miles of carriageway using self- propelled mobile transporters (SPMTs). Tandem lifting was used to erect the deck over multiple lanes below. The bridge was set on temporary piers ready for welding and, ultimately, was suspended from the pylons by steel cables. Landing the prefabricated main span deck of this landmark structure was completed within one day, resulting in reduced road closures and disruption to the travelling public as well as less temporary support requirements over a segmental insitu fabrication alternative.

Excavation and Ground Support

These hyperlinks provide examples of excavation and ground support:


Sheet Piling Push and Dig Method Safe System of Work Animation


Trench Boxes: Typical Installation Methodology

Dewatering

These hyperlinks provide examples of dewatering:

Dewatering Wellpoint Installation

Demolition

These hyperlinks provide examples of demolition:


Demolition Sequencing, Propping & Temporary Works Design 

The Churchill Way flyovers were a pair of dual carriageway flyovers that connected Lime Street to Dale Street and Tithebarn Street in central Liverpool. They opened in 1970 and were designed to form part of the city’s cancelled inner ring road scheme.  The flyovers were closed in September 2018 due to structural issues related to the post-tensioning and the decision was made to demolish them. 

The inner-city location of the flyovers and the small site area meant that the demolition sequence had to be highly choreographed to overcome the logistical challenges that this created.  The flyovers were removed by cutting the structure into span length sections and using SPMTs to move them to a central processing compound.  The spans were lowered onto steel grillages before cutting them into sections to be hauled offsite on low loaders.  The four most eastern spans of the North and South flyovers were demolished using more traditional demolition techniques with the spans being processed by excavators equipped with shears and munchers.