New Dartford Flyover RIides On Weber Five Star* Grout SP
Published by Jackie Biggin for Weber in Local Government
The recent improvement scheme of the roads network around the Dartford Crossing has included a new flyover over the A2 and M25. The sweeping curves of this elevated section are carried on 80 cast concrete columns each of which carries a bridge bearing supporting the roadway itself and allowing the expansion movement of the roadway structure. The high level of vibrations generated by the virtually continuous traffic flow at these points of connection demanded the highest quality of fixing. Each of the 80, 800 x 800mm, giant bearing packs is grouted to the top of the columns with Weber Five Star* grout SP.
The scheme, which was carried out by Costain Ltd at a cost of £120m, included new roads linking the northbound A282 and the eastbound A2, as well as new lanes on the A2 westbound for traffic joining the M25, and a fourth lane in each direction on the A2 between the M25 and Bean Junction, a distance of 2kms. Two new viaducts have been constructed as well as the flyover. The scheme has improved journey time, reliability and safety, and has reduced congestion by removing around 40% of vehicles using M25 Junction 2. Reduced noise and improved dense landscaping has benefitted the local environment considerably.
Weber Five Star* grout SP is a premixed, high-flow, high-strength, shrinkage-compensated cementitious precision grout especially designed for the fixing of bridge bearings, rails, machinery installation and underpinning. It is formulated from specially selectedPortlandcements, graded aggregates, and admixtures including a special form of carbon. The product meets the Highways Agency specification for Highway Works Vol. 1, clause 2601.
The Five Star* grout SP is poured into a shuttering box surrounding the bearing mounting. This grout can also be pumped in difficult to reach areas. It can be applied in thicknesses from 10mm to 50mm and can be used in a range of temperatures and site conditions. It has high initial and long term strength properties developing a compressive strength of 40N/mm² in just seven days from application and 60N/mm² in 28 days.
Next time you are approaching the Dartford Crossing from the Kent direction remember that the whole of the A2 link flyover is riding on moving bearings supported in place by Weber Five Star* grout SP.
Call 08703 330070 for further information on Weber’s comprehensive range of construction mortars, which includes concrete repair, precision grouting, bedding mortars and structural strengthening systems, or visit www.netweber.co.uk. Here you can request a copy of the latest Construction Solutions handbook in either print or CD format.