Our second week

At the start of our second week on the project, we completed the deck, and with the dead load sag level confirmed on the cables, the grouting/backfilling/concreting of the live end began. 

Every able-bodied person on site jumped back into the "pit", and the process was completed within 1.5 days - no mean feat considering the searing heat and thunderstorms passing overhead.

By Wednesday, the bridge was complete, and the fencing on both the approach ramps and the site clearance was finished. 

We celebrated by playing a game of soccer with the local team, before hosting a BBQ on site for everybody who had worked on the project with us.

The official opening

The bridge was officially opened at 10.30am on Friday, 16 November, in front of a crowd of more than 400 people, including TV camera crews.

Notwithstanding the large group of local politicians present, the opening ceremony itself was very different to any I had attended before.  A DJ began spinning the decks and an MC began working the crowd from 9.00 am that morning, and two separate time slots within the proceedings were allocated to dance and celebration.

And, you just knew the craic was good when the bodyguard of one of the dignitaries, who was dressed in full military fatigues, started dancing with everybody else.

Making a difference

As with so many projects, once we arrived on site, our team became so focused on delivering the bridge that, at times, we lost sight of just how much a project like this can mean to the local community.

This was brought sharply back into focus for us during the opening ceremony when one of the community leaders described how, during the rainy season every year, several children are swept away at the crossing.  He also shared a harrowing story of a woman in labour who, in trying to cross the swollen river to get to the local hospital, was forced back by the water.

When you hear stories like these, it really makes you appreciate the positive impact our work in building the new bridge will have on the local community. Hitting a deadline or a project milestone can suddenly feel quite unimportant when compared with making a real and positive difference to people’s daily lives. 

Our team is extremely proud of the small part we played in improving the lives of the people in this small Rwandan village, and we are very grateful to have been given the opportunity to do so.

The solution

The bridge is a 37m span suspended (stress ribbon) bridge.  It consists of 2 No. handrail cables and 2 No. deck cables. 

The deck was formed with 38 No. cross beams, located at 1m centres, made with a combination of steel and timber and placed on top of the walkway cables. 

The walking surface consists of a series of 2m long timber planks, placed 5 abreast, laid on top of the cross beams. The cross beams were connected firstly to the cables by 10mm dia. reinforcing bars acting as stringers, and secondly, to the walkway cables by manually bending the stringer around both the cable and the cross beams. 

For the handrail cable connection, the stringer was manually looped around handrail cable. A wire mesh was then attached to the handrail cable and deck to 'fill the gap' between the cables.

The cables were anchored in both abutments by passing them through a concrete anchor beam and clamping the cable against itself with a series of drops forge anchors. 

When our team arrived to site, the abutment walls and tiers had been built, so once the cable sag was set, the abutments were backfilled with stones of varying sizes and layers of mortar. 

Finally, fence posts were installed, and a 100mm deep approach slab was formed over the entire top surface of the abutment.