熱プレストレス工法を連続合成桁橋へ適用した場合のクリープ・乾燥収縮の影響に関する解析的研究
キーワード:
熱プレストレス工法,連続合成桁,クリープ,乾燥収縮
2007 年 14 巻 56 号 p. 31-42
詳細
2007 年 14 巻 56 号 p. 31-42
To secure the durability of the continuous composite girder bridges, the crack control method by pc bars or stress control methods by prestressing are generally adopted for the tensile stresses induced to the concrete-slab at an intermediate support. For the stress control methods by the prestressing, i.e. jack-up-down method and method by prestressing pc bars are popular ones. However, both the methods are effective against the serviceability limit state, but not sufficient against the ultimate limit state of bridges. In order to improve the ultimate limit state, a thermal prestressing method was investigated in this paper. Particulaly, the effects of creep and shrinkage on the variations of stresses induced through the thermal prestressing method were detailed by illustrating the affections for a continuous composite girder bridge with two spans. Also suitable time and amount of additional prestressing are discussed herein.
