けい酸カルシウム板の中性化と留付け強度低下に関する研究:－天井落下事故を生じた材料の分析－ [in Japanese] CARBONATION AND FASTENING STRENGTH DETERIORATION OF CALCIUM SILICATE BOARD:-Analysis of materials collected from a ceiling collapse accident- [in Japanese]
Access this Article
Aging of calcium silicate board is discussed in the present contribution. Recently, the fall of sealing which is composed of calcium silicate board has been reported at times. The mechanism of aging phenomena of calcium silicate board is not wholly understood. For this reason, the chemical analysis and physical property experiment on the aged and newly provided material are conducted and comparison of those results is made. It is experimentally confirmed that tobermorite in calcium silicate board can be carbonated and resultantly it causes decreasing of density, increasing of water vapor BET surface area and water penetration rate, and decrease in strength. The weight of calcium silicate board per strength can be dropped as it is about 12.5% of original value. It is expected that relatively high water content enhances carbonation rate because carbon dioxides dissolves in it and makes carbonic acid. Therefore, it is strongly recommended that calcium silicate board is only used in the drying condition.
- Journal of Structural and Construction Engineering (Transactions of AIJ)
Journal of Structural and Construction Engineering (Transactions of AIJ) 78(689), 1203-1208, 2013
Architectural Institute of Japan