抗扰动快硬高延性混凝土的制备

Preparation of anti-disturbance rapid hardening high ductility concrete

为满足交通工程对修复材料提出的抗扰动、抗裂、增韧及快硬的实际需求,研究了缓凝剂、纤维类型及扰动对快硬高延性混凝土早龄期力学性能、凝结时间的影响。结果表明,不同纤维增强快硬高延性混凝土24h龄期抗折强度与抗压强度均分别超过了22MPa、43MPa,表现出快硬特征;PE纤维增强快硬高延性混凝土表现出超大的延伸率、明显的多缝开裂现象和极小的平均裂缝宽度,抗扰动性好;钢纤维增强快硬高延性混凝土表现出极大的抗拉强度、抗压强度、抗折强度,但延伸率极低,无多缝开裂现象,抗裂性能差,抗扰动性差;PVA纤维增强快硬高延性混凝土虽然有多缝开裂现象和较大的延伸率,但裂缝平均宽度大,大于0.2mm,且裂缝数量少,抗裂性能较差,抗扰动性较差;2%体积掺量PE纤维增强快硬高延性混凝土具备极优的增韧、抗开裂、抗扰动性能,非常适合在不中断交通情况下使用。将制备的抗扰动快硬高延性混凝土在某快速路混凝土路面的结构修补中得以应用,取得了良好的抗扰动、抗裂与增韧效果。

In order to meet the actual demand of anti-disturbance, anti-cracking, toughening and rapid hardening in traffic engineering repair material, this paper researches the influence of retarder, fiber type, disturbance of rapid hardening high ductility concrete.The results show that different fiber reinforced rapid hardening high ductility concrete flexural strength and compressive strength are more than 22 MPa and 43 MPa at 24 h age, which shows rapid hardening characteristics. The PE fiber reinforces rapid hardening high ductility concrete showed large elongation, noticeable more seam cracking phenomenon and the minimum of the average crack width,anti-disturbance performance is excellent;The steel fiber reinforces rapid hardening high ductility concrete show great tensile strength, compressive strength, flexural strength, but the elongation rate is extremely low, no more seam cracking phenomenon, antidisturbance and anti-cracking performance are poor too. The PVA fiber reinforced rapid hardening high ductility concrete shows more seam cracking phenomenon and the larger elongation, but the average crack width is large, greater than 0.2 mm, crack number,anti-cracking and anti-disturbance performance are poorer too;The PE fiber reinforces rapid hardening high ductility concrete with2% volume content possess excellent toughening, anti-cracking, anti-disturbance performance, using in the case of uninterrupted traffic is very suitable. The anti-disturbance rapid hardening high ductility concrete is applied to the structural repair of a expressway concrete pavement, and good anti-cracking, anti-disturbance and toughening effect are obtained.