• 10.07.17 28.07.17

Compressed earth blocks production for FORT V


BC architects & studies

Wayne Switzer, Cedric Evrard, Het Leemniscaat bvba

3 weeks + 2 extra sessions


A 3 weeks Compressed Earth Blocks (CEB) workshop organised to build  FORT V

During the summer of 2017, BC studies organised a workshop to produce Compressed Earth Blocks made from local clay called "Boomse klei", which was sourced from the nearby quarry in Boom, Belgium. The blocks were made inside a warehouse, which would also host  FORT V for which the blocks were meant.

As a preparation, specimen tests were made before the workshop, to define a good mix of source materials, arriving at a normalised compression force of 4 MPa, which made the building conform to Eurocode 3 for masonry works.

Clay from the quarry was delivered in the warehouse, and spread out to dry on the floor surface of 500m2 for 6 times, in an interval of 4-5 days. The dry clay blocks were subsequently crushed into powder.

The workshop then received 40 people divided over 3 groups, a week for each, and 2 supplementary sessions on an evening and a Saturday. A group would mix earth, sand and water in a planetary mixer, control the mix, and compress it into a block with the help of a hydraulic press. The blocks would then be stacked onto pallets for drying. In total, 19000 blocks were produced, at a rate of maximum 6 per minute, or 140 per hour or around 950 per day.

Each day at lunchtime, different lectures on earth construction were held, and each week had an external lecturer.