CEMENT COMPOSITE STAY-IN-PLACE FORMWORK: A CONCEPT FOR FUTURE BUILDING SYSTEMS

摘要

The use of a recently developed inorganic phosphate cement with grain sizes less than 100 micrometer in combination with an adapted manufacturing process creates the possibility to obtain cement composites with a never been seen fiber volume ratio (V_f) of up to 25-30%, a factor 2 to 10 times higher than conventional cement composites. The forthcoming gain in tensile strength enables the material to be used in high performance building applications such as sandwich panels, structural claddings and concrete repair. This paper presents a concept for a lightweight stay-in-place cement composite formwork taking advantage of this new promising material. Full scale tests analyzing the structural behavior indicate the opportunities of this innovative forming technique. Results also show an improved mechanical behavior of the composite (concrete-formwork) beam as the micro cracking phenomenon of concrete in tension is better controlled and crack propagation is delayed compared to a traditional steel reinforced concrete beam.