The use of steel reinforced concrete facade is gradually becoming unpopular because of the damage caused to the elements as a result of corrosion of the steel reinforcement. It is now possible to build lightweight and...The use of steel reinforced concrete facade is gradually becoming unpopular because of the damage caused to the elements as a result of corrosion of the steel reinforcement. It is now possible to build lightweight and slender concrete structures which are invulnerable to corrosion with the use of fiber reinforcements, which are gradually replacing the corrosion prone steel. This paper describes the construction of faqade panels made of rattan cane reinforcements and steel reinforcements, ten number model sized elements of area 0.15 m2 and a depth of 40 mm were considered, with five panels for each reinforcement type. The elements were subjected to incremental load of 1 kN until failure occurred. Deflections were measured for each element, and crack width was measured at failure load. The results for both types of reinforcements when compared showed the rattan cane reinforced panels failing earlier than the steel reinforced panels. However a lower defection and crack width was recorded in the rattan cane reinforced panel. This paper concludes that the lower crack width formed after failure in the rattan cane reinforced panel gave it advantage over the steel reinforced panel, since it has lower space for the ingress of water which is the main agents of corrosion.展开更多
In situ testing provides accurate characterization of existing degradation mechanisms of materials and building systems which helps reducing the subjectivity of visual inspections especially when ageing under natural ...In situ testing provides accurate characterization of existing degradation mechanisms of materials and building systems which helps reducing the subjectivity of visual inspections especially when ageing under natural ageing conditions is carried out over significant periods of time. In this work, data collected from field experimental campaigns over 10 years after construction using several premixed one-coat rendered walls and over 4 and 6 years after construction in the case of ETICS (external thermal insulation composite systems) are presented and discussed. The influence of hydrophobic agents on the performance of both types of facades in terms of surface condition and water penetration was assessed by visual inspections, Karsten test and capillary tests. Additionally, adhesion tests and subsequent evaluation of porosity were also carried out for premixed one-coat mortars. The results obtained have shown that ageing of the rendering solutions, especially after 5 or 6 years in-service, results from the loss of resistance to liquid water penetration, especially at the surface. Yet, additional mechanisms such as leaching of hydrophobic agents and photochemical degradation are thought to be involved, too. Moreover, the results obtained using the Karsten test proved to be the most reliable method to determine the loss of water penetration resistance and predict the ageing of facade solutions. The information collected and the correlations established can help developing solutions to prevent early ageing and implement appropriate maintenance plans to delay their effect.展开更多
文摘The use of steel reinforced concrete facade is gradually becoming unpopular because of the damage caused to the elements as a result of corrosion of the steel reinforcement. It is now possible to build lightweight and slender concrete structures which are invulnerable to corrosion with the use of fiber reinforcements, which are gradually replacing the corrosion prone steel. This paper describes the construction of faqade panels made of rattan cane reinforcements and steel reinforcements, ten number model sized elements of area 0.15 m2 and a depth of 40 mm were considered, with five panels for each reinforcement type. The elements were subjected to incremental load of 1 kN until failure occurred. Deflections were measured for each element, and crack width was measured at failure load. The results for both types of reinforcements when compared showed the rattan cane reinforced panels failing earlier than the steel reinforced panels. However a lower defection and crack width was recorded in the rattan cane reinforced panel. This paper concludes that the lower crack width formed after failure in the rattan cane reinforced panel gave it advantage over the steel reinforced panel, since it has lower space for the ingress of water which is the main agents of corrosion.
文摘In situ testing provides accurate characterization of existing degradation mechanisms of materials and building systems which helps reducing the subjectivity of visual inspections especially when ageing under natural ageing conditions is carried out over significant periods of time. In this work, data collected from field experimental campaigns over 10 years after construction using several premixed one-coat rendered walls and over 4 and 6 years after construction in the case of ETICS (external thermal insulation composite systems) are presented and discussed. The influence of hydrophobic agents on the performance of both types of facades in terms of surface condition and water penetration was assessed by visual inspections, Karsten test and capillary tests. Additionally, adhesion tests and subsequent evaluation of porosity were also carried out for premixed one-coat mortars. The results obtained have shown that ageing of the rendering solutions, especially after 5 or 6 years in-service, results from the loss of resistance to liquid water penetration, especially at the surface. Yet, additional mechanisms such as leaching of hydrophobic agents and photochemical degradation are thought to be involved, too. Moreover, the results obtained using the Karsten test proved to be the most reliable method to determine the loss of water penetration resistance and predict the ageing of facade solutions. The information collected and the correlations established can help developing solutions to prevent early ageing and implement appropriate maintenance plans to delay their effect.