Specialised Ferro Cement Structures from Kenya Boats.

 

Kenya Boats Ferro Cement Products

Application

The term Ferro cement is most commonly applied to a mixture of Portland cement and sand applied over layers of woven or expanded steel mesh and closely spaced small-diameter steel rods rebar. It can be used to form relatively thin, compound curved sheets to make hulls for boats, shell roofs, water tanks, etc. It has been used in a wide range of other applications including sculpture and prefabricated building components. Kenya Boats has specialized with this product to make affordable fashionable housing for the Mombasa area.

History

The term "ciment armé" was given to this product by its inventor in France,Joseph Monie. Another inventor in France, Joseph-Louis Lambot constructed a small boat in 1848 by casting wire and rods into the form and the boat was exhibited it at the Exposition Universelle in 1855. A patent for Lambot's construction technique was applied for that year with the name "ferciment". The patent was granted in Belgium but only applied to that country and unfortunately went no further. At the time of Monier's first patent, on July 16, 1867, he wanted to create large urns, planters, and cisterns without the common failures of kiln firing clay in larger sizes. In 1875 he went on to expand his patents to include bridges and designed his first steel and concrete bridge. The outer layer was sculpted to mimic rustic logs and timbers, thereby also introducing Faux Bois concrete into common practice.

Ferro concrete has relatively good strength and resistance to impact. When used in house construction in developing countries, it can provide better resistance to fire, earthquake, and corrosion than traditional materials, such as wood, adobe and stone masonry. It has been popular in developed countries for yacht building because the technique can be learned relatively quickly, allowing people to cut costs by supplying their own labor. In the 1930s through 1950's, it became popular in the United States as a construction and sculpting method for novelty architecture, examples of which created "dinosaurs in the desert".

Construction


The desired shape may be built from a multi-layered construction of mesh, supported by an armature, or grid, built with and tied with wire. For optimum performance, steel should be rust-treated, or stainless steel. (In early practice, in the desert, or for exterior scenery construction, "sound building practice" was not considered, or perhaps unknown as it grew in some cases, from a folk craft tradition of masons collaborating with blacksmiths.) Over this finished framework, an appropriate mixture grout or mortar of Portland cement, sand and water and/or admixtures is applied to penetrate the mesh. During hardening, the assembly may be kept moist, to ensure that the concrete is able to set and harden slowly and to avoid developing cracks that can weaken the system. Steps should be taken to avoid trapped air in the internal structure during the wet stage of construction as this can also create cracks that will form as it dries. Trapped air will leave voids that allow water to collect and degrade (rust) the steel. Modern practice often includes spraying the mixture at pressure (a technique called shotcrete).

Economics


The economic advantage of ferro concrete structures is that they are stronger and more durable than some traditional building methods. Depending on the quality of construction and the climate of its location, houses may pay for themselves with almost zero maintenance and lower insurance requirements. Water tanks could pay for themselves by not needing periodic replacement, if properly constructed of reinforced concrete.
Ferro concrete structures can be built quickly, which can have economic advantages. In inclement weather conditions, the ability to quickly erect and enclose the building allows workers to shelter within and continue interior finishing.
There are basically three types of methods of ferrocement. They are following

Advantages


The advantages of a well built ferro concrete construction are the low weight, maintenance costs and long lifetime in comparison with purely steel constructions. However, meticulous building precision is considered crucial here. Especially with respect to the cementitious composition and the way in which it is applied in and on the framework, and how or if the framework has been treated to resist corrosion. As seen from the picture to the left it can withstand very hot temperatures you can even cook your Pizza!!!

When a ferro concrete sheet is mechanically overloaded, it will tend to fold instead of break or crumble like stone or pottery. So it is not brittle. As a container, it may fail and leak but possibly hold together. Much depends on techniques used in the construction.
Please note: Much more information for projects of reinforced concrete has been updated regularly, than for products that we call ferrocement or ferro concrete.

For more information on this fantastic product and how we can work with you using Ferro Cement to make your building faster, safer, and cheaper get in touch with us on the information below.

For More Information contact Sales email: info@kenyaboats.com Tel:+254 (0)711 239213/734 401884