钢纤维混凝土在龙角山水库加固工程中的应用

Application of steel fiber concrete in consolidation works of Longjiaoshan res ervoir

在对龙角山水库溢洪道底板、挑流坎进行除险加固时,采用了钢纤维素混凝土(C25、F150).混凝土厚度20 cm,混凝土骨料粒径不大于20 mm和不大于钢纤维长度的2/3;钢纤维在混凝土中的体积率不小于1%,钢纤维长度在25～50 mm之间,直径在0.3～0.8 mm之间,钢纤维表面不得粘有油污和其他妨碍钢纤维粘结的杂质,其他杂质总重量不得超过钢纤维重量的1%.龙角山水库溢洪道泄槽经过数次行洪考验,虽然洪水中有部分风化碎石及沙砾等粒料,但并未对泄槽表面造成任何损伤,太阳暴晒和冰冻也没有造成泄槽表面象普通混凝土那样经常出现的细小裂纹,使用效果良好,由此可见,混凝土加入钢纤维能明显改善混凝土性能,有效提高混凝土的抗疲劳性、耐磨性、耐冲刷性.

Steel fiber concrete(C25, F150) was used to strengthen the spillway bo ttom plate and bucket of Longjiaoshan reservoir, with the concrete thickness of 20 cm, the concrete aggregate size not greater than 20 mm and not greater than t wo thirds of the length fiber, the volumetric ratio of steel fiber in concrete n ot less than 1%, the steel fiber length of 25～50 mm, the steel fiber diameter o f 0.3～0.8 mm. Concrete design also required that greasy dirt and impurities sho uld not be adhered to the surface of steel fiber and that the total weight of ot her impurities should not exceed one percent of the weight of steel fiber. The s trengthened spillway channel has experienced several tests of flood release. Alt hough the flood flows carried some weathered rubble and gravel, the surface of t he spillway channel was not damaged by these granular materials. The channel sur face’s exposure to the solarization or freezing circumstances did not brought a bout any small cracks that usually arise in conventional concrete. Adding s teel fibers to concrete can remarkably improve behaviors of the concrete and eff iciently rais e fatigue resistance and erosion-abrasion resistance of the concrete.