Help needed with building suspended cable bridge

[gibbon]

I have been working with a project in West Africa with a view to starting canopy tourism in the region.

 

We are at a stage now where funding appears to be just around the corner and we have firm plans for the 1st phase. We are building 2 structures with different levels between 3 and 9m in height. These 2 structures will be linked with 2 cable suspension bridges that will span 50-55m accross a mangrove swamp complete with crocodiles. There will also be some more challenging crossings and a zip line back to the edge of the river. It is hoped that this should be up and running by xmas this year.

 

I am looking for someone who has experience building suspended bridges who may like to get involved in what could be an exciting project.

 

PM me for further details.

[Ian Leach]

Sounds like fun you could contact go ape as they have done the rope bridges and zip lines the might be able to advise or give you a contact on who done there's .

[gibbon]

I know go ape would be a good contact but at the moment we are still working out the budgets. This is something untill now I have been doing on a voluntary basis for the reserve. What we really need is someone who has built this type of bridge and over this span who wants to get involved.

 

The the aim of the project is to generate funds from the land to help protect the wider reserve from deforestation.

[gibbon]

Still looking for help.

 

Below is an extract from an email to a leading structural engineer but we are keeping all options open and extend the offer to anyone who can help

 

"We now have developed an idea to build two structures at the ****** site. It is hoped that this will be the first stage of something that can be expanded attracting more tourists to the area to secure its future as a reserve, which at the moment is far from certain.

 

 

 

These structures will be two stories with a platform at 3m and one at 6m. One structure will be on a riverbank and the other 50m away in the mangrove swamp. We need help in designing either one large (two way), or two narrower (one to travel in each direction) suspended walkways between the structures. This bridge will connect the lower levels of the structures at 3m. It is important that this should be suspended and have a boarded or similar walkway to cater for people of all ages. What we do not have is the engineering skills to design this walkway, how it will be attached to the structure and what would be a suitable design for the supporting towers. Obviously the design of the towers would play a very important part of the system, but they would need to be constructed from locally available materials. This is where we hope you may be able to help us.

 

 

 

At the higher 6m platforms, we hope to build a more challenging crossing to reach the mangrove structure. This would be of a “Go Ape” type crossing with different swinging obstacles to negotiate where guests are connected by harness to a safety cable. Upon reaching the mangrove structure there will be a zip line at 6m back across the river to finish. This second crossing option and the zip line I assume would be also connected to the same towers as the foot bridge at 3m.

 

 

 

We would be extremely grateful for as much or as little assistance as you are able to give us. The best possible scenario for us at this stage is that someone is willing to help us in building this. If this is not possible we hope that you may be able give us sufficient assistance to allow us to get something part built in the UK which we could assembled once in *****. If you were in a position to help we would have no problem with you using your involvement in the project to promote your own business. There is the offer of a flight and accommodation at the lodges if required"

[coolie]

. Obviously the design of the towers would play a very important part of the system, but they would need to be constructed from locally available materials. This is where we hope you may be able to help us.

 

Im no Engineer,Im just wondering what are the local materials?

[kevwrenn]

Never done anything on this scale, but i would think you'd need some bloody deep foundations or pilings to support a 50m walkway. Once you get the weight of a couple of people 25m from the support there will be some pretty big forces unleashed. The tension you'd need to keep the centre well above ground/swamp level would be immense. I must add, my only experience is of small scale wooden projects with the scouts.

[gibbon]

We have a range of materials we could get locally, I beams, and concrete but the prefered method would be a type of compressed mud block that can be re-inforced with concrete and steels. They use theses to support water towers.

 

I'm no engineer either thats why we are looking for help. I guess that by running the cables over or through the towers and secured to a hefty ground anchor, the lever pull on the towers can be reduced. This would load the towers more vertically not laterally where they have more stregnth.

 

I dont think the tension on the cables needs to be cranked right up. I reccon we will need 4 cables. 2 for the walkway and 2 higher load bearing cables. The higher load bearing cables can have a big sag so there is not too much tension and support a level walkway with cable or chain droppers.

[Ben]

Sounds like an amazing project, I wish you all the luck in the world, I think you might need it.

[minty]

Please keep us posted with any progress,Im intrigued.