Computer Modeling to Build Better Mud Bricks

Rammed earth and stabilized mud block or brick are cheap, easy to make, usually durable materials widely used for building homes and low-level structures, especially in developing countries. Despite their widespread use and long history, the structural properties of these materials are not well understood, so how they could be manufactured to better withstand destructive natural forces, such as earthquakes and weathering, remains a goal. Craig Foster, assistant professor of civil and materials engineering at the University of Illinois at Chicago, hopes a specially tailored set of computer models he is developing may provide the necessary answers. He has just won a three-year, $243,000 National Science Foundation grant to conduct the work.

Bio-Engineered Sand Brick

The winner of the 2010 Metropolis Next Generation Design Competition proposes a radical alternative to the common brick: don’t bake the brick; grow it. In a lab at the American University of Sharjah, in the United Arab Emirates, Ginger Krieg Dosier, an assistant architecture professor, sprouts building blocks from sand, common bacteria, calcium chloride, and urea (yes, the stuff in your pee). The process, known as microbial-induced calcite precipitation, or MICP, uses the microbes on sand to bind the grains together like glue with a chain of chemical reactions. The resulting mass resembles sandstone but, depending on how it’s made, can reproduce the strength of fired-clay brick or even marble. If Dosier’s biomanufactured masonry replaced each new brick on the planet, it would reduce carbon-dioxide emissions by at least 800 million tons a year. “We’re running out of all of our energy sources,” she said in March in a phone interview from the United Arab Emirates. “Four hundred trees are burned to make 25,000 bricks. It’s a consumption issue, and honestly, it’s starting to scare me.” Read more…

Yakhchal: Ancient Refrigerators


Yakhchal in Yazd Province

By 400 BC, Persian engineers had mastered the technique of storing ice in the middle of summer in the desert. The ice was brought in during the winters from nearby mountains in bulk amounts, and stored in a Yakhchal, or ice-pit. These ancient refrigerators were used primarily to store ice for use in the summer, as well as for food storage, in the hot, dry desert climate of Iran. The ice was also used to chill treats for royalty during hot summer days and to make faloodeh, the traditional Persian frozen dessert.

Aboveground, the structure is comprised of a large mud brick dome, often rising as tall as 60 feet tall. Below are large underground spaces, up to 5000m³, with a deep storage space. The space often had access to a Qanat, or wind catchand often contained a system of windcatchers that could easily bring temperatures inside the space down to frigid levels in summer days.


NimVar Yakhchal


Image Credit


Image Credit


Image Credit

The Yakhchal have thick mud brick walls that are up to two meters thick at the base, made out of a special mortar called s?rooj, composed of sand, clay, egg whites, lime, goat hair, and ash in specific proportions, and which was resistant to heat transfer. This mixture was thought to be completely water impenetrable.


Meraji Yakhchal

The massive insulation and the continuous cooling waters that spiral down its side keep the ice stored there in winter frozen throughout the summer. These ice houses used in desert towns from antiquity have a trench at the bottom to catch what water does melt from the ice and allow it to refreeze during the cold desert nights. The ice is broken up and moved to caverns deep in the ground. As more water runs into the trench the process is repeated.


The twin ice-pits on Sirjan, Kerman Province, are surrounded by high walls and were constructed 108 years ago with mud-brick, the ice-pits are surrounded by high walls.

Earthquake Resistant Housing

Specialist earth builder, President of the Earth Building Association of Australia, and guest researcher in the Faculty of Engineering and Information Technology, Peter Hickson, has combined one the world’s most ancient building techniques, “cob” construction, with modern engineering methods to develop a model house as part of an effort to createlow cost earthquake resistant housing for millions of people around the world. Hickson’s house introduces many new technologies, but what makes his system unique structurally is the addition of internalbamboo reinforcing and the use of structural diaphragms. Read more about Hickson’s research.

Earthquake Proofing Traditional Peruvian Houses

Since 1970, Peru has been hit by five powerful and deadly earthquakes. The latest struck Peru’s coast exactly two years ago with a magnitude of 8.0 on the Richter scale. It fiercely shook the capital Lima, but its devastating epicentre was about 200km (124 miles) to the south, near the town of Pisco, a small fishing port built largely of adobe – mud bricks which Peruvians have used for thousands of years. For Peruvian engineer Marcial Blondet, it was the devastating quake in 1970 that first motivated him to develop earthquake-resistant buildings, particularly for those who could least afford them. Mr Blondet and his team found a solution in an industrial plastic mesh used by mining companies to hold back earth on slopes. It is strong, cheap and easy to use. Securely enveloping a normal mud-brick home in the mesh can prevent the walls from collapsing in an earthquake. The building wobbles but it does not fall down.

Radiolaria Pavilion

Andrea Morgante, founder of Shiro Studio, has collaborated with D-Shape to produce the Radiolaria pavilion, a complex, free-form structure produced using the world’s largest 3D printer. Measuring 3 x 3 x 3 metres, the structure is a scale model of a final 10-metre tall pavilion to be built in Pontedera, Italy, in 2010. D-Shape developed the first large-scale stereolithic printer in 2008 aiming to offer architects the design freedom that rapid prototyping allows them but has so far been confined to scale models. When D-Shape commissioned Andrea Morgante the design for the first large-scale structure to be printed the ultimate aim was to produce a geometry that could be self-supporting and demonstrate the capabilities of this innovative technology: being made of artificial sand-stone material and without any internal steel reinforcement the pavilion’s design and execution had to be intrinsically resilient to several static stresses.

The printing process takes place in a continuous work session: during the printing of each section a ‘structural ink’ is deposited by the printer’s nozzles on the sand. The solidification process takes 24 hours to complete. The new material (inorganic binder + sand or mineral dust) has been subjected to traction, compression and bending tests. The results have been extraordinary and the artificial sandstone features excellent resistance properties. Effectively this process returns any type of sand or mineral dust back to its original compact stone state. The binder transforms any kind of sand or marble dust into a stone-like material (i.e. a mineral with microcrystalline characteristics) with a resistance and traction superior to portland cement, to a point where there is no need to use iron to reinforce the structure. This artificial stone is chemically one hundred percent environmentally friendly.