Wednesday, March 24, 2010

Tuesday, March 16, 2010

Construction – All walls started

The site in the morning; all the walls have been started and we are on our way to having the first layer of every wall by the end of the daySetting up Form3.1, the imporved form is stronger and straighter than Form3 but the blue rope becomes elastic in the sun and allows the from to creap open. More heavy cord will have to be bought in Kigali, as it is not available here. The start of the living room wall. This will be the single largest mass of rammed earth in the entire house and will hopefully be somthing of a show piece.The Master Mason Paul inspects the start of the livingroom wall The team of 'Helpers' who carry the earth from the pit to the site using the remains of broken plastic jerrycans as buckets

Construction – Wall Repair

Two otherwise excellent sections were marred by a broken joint: it was time to experiment with some repair techniques. Two otherwise excellent sections were marred by a broken joint: it was time to experiment with some repair techniques.

Two otherwise excellent sections were marred by a broken joint: it was time to experiment with some repair techniques. This successful repair was done by pounding earth into the hole with the end of the wooden block, and finished with the side of the block to level it with the surrounding surfaces.

Formwork - Form3.1


Our third functional formwork, Form3.1. The same basic design as Form3 but with a few improvements: stronger side panels made from Cyprus instead of pine, and evenly spaced clamping frames to allow for easier shuffling of the frame along the walls.

Form3 – First Section

Form3 - first test Form3 - broken endgate, this was replaced with one with the planks orientated horizontally to avoid this.Form3 - Releasing the first sectionForm3 - Moving the formwork    Form3 - Success: the first section

Monday, March 15, 2010

Site Visit

Cheryl, Adam and the local kids inspect the walls  Our first enclosed room ( the walls will be higher soon )

Sunday, March 14, 2010

Formwork – Formwork mark 3

Thanks to some advice from Rowland at Ram Cast CIC, Form3 is free of bolts and hopefully a lot quicker to put together because of that. The design is based on the example here

form3_General assm.

Form3 assembled. Not shown is the rope wound around the top of the posts

form3_exploded view. Form3 disassembled, showing the side panels and the clamping frames
form3_Clamping-frame. Detail of one of the clamping frames; the joins are not glued as they’re taken apart each time  the frame is moved.
OLYMPUS DIGITAL CAMERA And here is the first attempt.






Construction – More walls


Two goats-of-approval The walls are so good that even the goats like them.
Keep on ramming The second frame for the day and it is only 0830

Thursday, March 11, 2010

Monday, March 8, 2010

Formwork – Formwork 2 test

schpeal coming soon, in the interim mouse-over for details.

Assembling Fromwork2Bad Weld on through-bolt breaks during assembly   Rammign the first course Ramming the last course The master mason showing off the second lift Cracks showing up on the first lift beacuse of the soil being to dampThe finished surface of the first lift.

Formwork 2 - Fabrication

After the failed first test a number of lessons were learned: that the form needed to be stiffened dramatically to stop flexing, the areas around the bolts needed reinforcing and the form needed to be narrowed by a couple of centimeters to protect the edge of the foundation cap.

The materials of Formwork 1 were recycled to form the basis of formwork2. A new set of braces and brackets were fitted to the outside of the forms, and the clamps were replaced with pairs of through-bolts.

Stripping_Form1 Form2_BracesFinished_side

Formwork – Test

The formwork was constructed by local carpenters using a locally available pine. The design was based on a rolling formwork design by Middleton. After some delays finishing the form and the mallets the testing began. Because it was late in the day, low section of wall under a window was selected to be the test wall.

Finishing one of the end-gates Loading the first course of earth 

It was immediately obvious that the timber was too green and soft for the number of braces used, as it started to flex in between the clamps on only the first course. As the ramming continued the foundation cap began to chip-off in a couple of places. A second course was added to one end section that wasn’t flexing and, before it was rammed firm, one of the end bolts pulled through.

Damage fromthe bolt pulling throughFirst wall test showing cracks from failing formwork

The rather paltry wall sample was left in place to see how it would fair in the elements and if it would firm up with time.