Capacity building

This week I started to get stuck into the more strategic aim of my placement, which is to build ground engineering capability within the MASS engineering team. Up to now I have either been really busy on project work or checking things on site, or just generally trying to find my feet. But the purpose of the placement is not so much for me to do design work myself, but to leave the team in a better position to make geotechnical decisions after I leave.

With that in mind, this week I delivered the first in a series of six (hopefully!) workshops on ground engineering. This one covered basic soil mechanics, the idea being that it would be a refresher for those who covered some geotechnics at university or a basic introduction for those who didn’t. I wanted to make sure that everyone understands the terms and concepts that will be used in later sessions on things like foundation design, and also to get everyone to a point where they can read a standard geotechnical textbook without being confused and terrified by the terminology.

Workshopping with Aimable, James, Obed, Christian, Shakira, Charlotte, Alexia and Zani

Before delivering the session I really had no idea whether the content was way too basic or much too advanced. Given the range of experience in the team, it seemed likely that it would be both at once! I was surprised and pleased to find that I’d managed to pitch it about right. Various members of the team asked great questions which showed they understood what I was talking about, and also brought some really interesting examples from their own experience for discussion.

On Thursday I went to visit a local soil testing laboratory run by a company called GeoConsult. Alexia, Zani and I were given a tour by the lab manager Fabrice and lab technician Robert. It was really interesting to see their test facilities and learn more about their capabilities. It was also great to chat about ground engineering with Fabrice, who is a true enthusiast for the subject – the kind of person who spontaneously brings Karl Terzaghi into conversations. Anyone who knows me will know that’s a sure fire way to win me over.

Fabrice and Robert explaining oedometer testing

The road above the lab is currently under construction, and access to the lab is via this very solid bridge over a 3 m deep trench! My colleagues were not impressed.

Sabinyo

It’s been a busy week so it’s taken me a while to post this. Last weekend we crossed the border into Uganda to climb a volcano called Sabinyo. The name means “tooth” in Kinyarwanda and apparently it’s named because it looks like an old man’s jagged teeth. One of the major attractions is that the summit is on the border between Rwanda, Uganda and DRC, so once at the top you can be in three countries at once!

The summit is at 3,645 m with around 1,700 m of ascent. It took us around 9 hrs (up and down) and felt like a pretty full on day. I have to say that the photos below really don’t do justice to the amazing beauty of the scenery and the outrageousness of some of the situations the route goes through. If you come to East Africa and don’t climb this volcano, you’re missing out!

First sight of Sabinyo. The mountain has 5 peaks, and the route goes up the left hand side as seen here to the top of the first peak; drops down and up again to the second; and finally up to the third and highest peak before retracing the route back down.

The route climbs briefly through bamboo forest before passing into this amazing afro-montane forest where all the trees are hung with moss.

The view across to Gahinga, which we climbed a few weeks ago, and behind it Murabura.

On top of the first summit; and looking across to the second peak. The climb up to this point felt pretty hard work and I wasn’t looking forward to losing height only to regain it again!

 

Much of the route consisted of ladders built from small branches, attached to the mountain by some undefined method. I tried to turn off my engineering brain and not think about the physics – which turned out to be surprisingly easy while surrounded by such stunning scenery.

 

Summit photo!

Looking down into Rwanda… Uganda… and DRC (thanks for pointing it out James!)

Descending the ladders was even more fun than going up. Watching people in front just disappear over a precipice into the mist was slightly disconcerting…

African Design Centre

Ever since I arrived I’ve been working on the design of a primary school in Ruhehe, northern Rwanda. This is a bit of a flagship project for MASS, because it’s being designed by the first ever cohort of students at the African Design Centre. There are 11 students, from a range of countries including Rwanda, Kenya, South Africa, South Sudan and (confusingly) Brazil. 10 of them are architects, and there’s a lone civil engineer, Zani, who spends a lot of time with our team.

The architects have decided that the centrepiece of the project should be a 5m high freestanding wall constructed from locally available volcanic stone, which will curve across the site boundary with classrooms radiating off from it. I have to admit it looks great on the renderings, but it’s proving to be very difficult to engineer to withstand seismic loads. It’s also quite expensive given that it serves no structural purpose. Things are further complicated by the site topography, which being in Rwanda is of course steeply sloping. This means the classroom buildings are on numerous levels and we need lots of earthworks and retaining walls to achieve the levels.

We’ve been doing loads of work on the interface between the freestanding wall and the classroom structures, and I’ve been thinking a lot about foundation and drainage design. This week Rosie and I held a coordination meeting with the ADC fellows where we attempted to explain some of the difficulties we’re having. It was great to discuss with them and understand their reasons for some of the decisions they’ve made, and hopefully they now understand some of the engineering implications better.

One of the problems we’ve had so far is that because there are so many architects working on the project, they change things all the time without necessarily thinking about all of the implications for the rest of the structure. As an example, this week they changed the pitch of the roof, which resulted in longer columns meaning the original section size no longer works. But because we weren’t involved until they had their hearts set on the change, it was very difficult to revert. This sort of coordination meeting is really useful to keep communication channels open.

Trying to explain why enormous overturning moments mean enormous foundations…

Rosie and me in accidentally complimentary kitenge outfits

The ADC