"[I]t was decided to develop a type of roofing based on prefabricated sections. ...With the partial results obtained in this stage, another part of the study could be initiated, i.e. to build this same type of element "in situ"... thus providing solutions for situations in which prefabrication is not appropriate..."
Ferrocement or ferro-cement is a system of construction using reinforced mortar or plaster applied over an "armature" of metal mesh, woven, expanded metal, or metal-fibers, and closely spaced thin steel rods such as rebar. The metal commonly used is iron or some type of steel, and the mesh is made with wire with a diameter between 0.5 mm and 1 mm. The cement is typically a very rich mix of sand an
"The first four layers of mesh were stapled to the mold over the plastic sheeting. Each length of mesh, already folded double, formed two layers. This first layer of mesh strips, 1-1/2 feet (457 mm) wide, was butted together. The second layer of mesh strips was laid out so as to cover the joints where the first layer was butted together, making a total of four layers of mesh."
Ferrocement"The vertical rods were stapled firmly to the hull. An air-powered staple gun was used..."
Ferrocement"Clear plastic 4-millimeter sheathing was hand-stapled to the mold for two reasons: ...To stop the moist mortar from falling through the joints and gaps between the wooden battens planking the mold. ...To form a barrier between the wooden mold and the fresh mortar. If no barrier were placed the wood would draw moisture from the new mortar and reduce its final strength."
Ferrocement"Two more layers of mesh were stapled over the mold. Again 1" x 2" (25.4 mm x 51 mm) wide staples were used. The folded mesh was not lapped but just butted."
Ferrocement"One-inch (25.4 mm) chain links were welded to the hull reinforcing cage where scuppers were to be placed. These links were aligned and welded in at deck level. ...[E]xposed steel pieces such as scuppers or screeds which require welding... should always be cleaned and protectively coated."
Ferrocement"[W]elded wire reinforcement (WWR) [was] formerly known as welded wire mesh or fabric. Welded steel wire reinforcement is the predominant form... A grid of orthogonal longitudinal and transverse cold-drawn steel wires is welded together at every wire intersection... The size and spacing of the wires can vary... based on the requirements... Welded wire reinforcement can be epoxy coated or zinc coated (galvanized). ...Plain and deformed welded wire reinforcement is covered in... ASTM A1064... Stainless steel wires are specified according to ASTM A1022... Epoxy-coated WWR... in accordance with ASTM A884... Galvanized WWR... with ASTM A1060... Even plain wire used in welded wire reinforcement has both chemical bond and mechanical bond to the concrete. The mechanical bond results from bearing of the welded cross wires against the concrete in the grid of reinforcement."
Ferrocement