COLLEY LANE SOUTHERN ACCESS ROAD

The Colley Lane Southern Access Road (CLSAR) is a new  carriageway in Bridgwater to provide access into the Colley   Lane Industrial Estate from the South. The £18.4m Colley   Lane Southern Access Road (CLSAR) plans include two new   bridges, 840 meters of carriageway and new cycle and   footways. 

The scheme will help ease congestion along Taunton Road   and Broadway by connecting Parrett Way to Marsh Lane,   providing access to the Colley Lane Industrial Estate from   the south. 

It will also open up brownfield development sites between   the River Parrett and Taunton and Bridgwater Canal to   support the delivery of planned housing and employment   land. The project involves the construction of bridges over   the River Parrett and over the Bridgwater & Taunton Canal. The geology of the site was characterised by highly   compressible, thick alluvial deposits associated with the   River Parrett floodplain and infilled clay pit. This creates the   risk for both excessively large and differential settlements   both along the embankment itself, as well as in relation to   relatively fixed approach embankments. 

The abutments on either side are proposed as MSE walls   (similar to Macwall) supported by a Paralink load transfer   platform over pile foundations. 

The current specifications include accounting for the weight   of high load requirements and the provision for future   heavier loads or the potential widening of the structure.   

The ParaLink LTPs will transfer loads of the mechanically  stabilised earth walls into the pile foundations beneath. 

The maximum height of the reinforced soil walls was approx.   4m above the Paralink LTP. 

For this purpose, four different ParaLink LTPs were designed   and installed considering edge piles of 600mm diameter and   internal piles of 450mm diameter, with 900mm diameter   circular pile caps. ParaLink allowed the spacing of the piles   to be increased to 2.5m in this particular scenario. 

The LTPs were constructed using Class 6I granular fill   material. Paralink 400, 500 and 800 were installed across   the site. The higher grade Paralink 800 was proposed for the   transverse and the Paralink 400 & 500 were used as   longitudinal reinforcement.

LTP04 and LTP 03 were constructed in 2018.