Case Study: Godavari Bridge

The 27th span of the third Godavari Bridge had ‘settled’ into the ground by approximately 160-200mm

In conjunction with Fosroc India, the railway authorities determined the best repair method was to undertake jacking and grouting

The entire operation had to be completed within a very limited time frame (approximately 4-5 hours) as the trains could not be stopped from passing over the bridge

The minimum strength requirement was 15 MPa in 1hr and  30 MPa in 3hrs

Fosroc’s recommendation included;

Fosroc Conbextra HES (High Early Strength) cementitious grout mixed with 12mm aggregate to reduce initial heat build-up and thermal cracking. This combination met the arduous performance requirements while being significantly cheaper than epoxy based grouts and avoiding significant exothermic problems with this product type

The bridge deck was raised using jacks to allow the installation of additional reinforcement and shuttering

Fosroc Conbextra HES, mixed with 50% 12mm down aggregates, was used to rebuild the thickness

Ice cold water was used to ensure sufficient working time as ambient temperature was between 45 - 48°C

Fosroc India provided a permanent and economical solution to a long-standing problem with no hindrance to rail traffic

The time and cost saving to the client was an added economical benefit introduced through the use of cementitious grout in place of higher cost polymer repair products