陈 鹏，金祖权，李建强，陈永丰

(青岛理工大学 土木工程学院，山东 青岛 266033)

盐渍土环境下高吸水树脂混凝土抗压强度及氯离子渗透研究

陈 鹏，金祖权，李建强，陈永丰

(青岛理工大学 土木工程学院，山东 青岛 266033)

标准养护和夏季自然养护的内养护混凝土在盐渍土环境中腐蚀不同龄期，测试其抗压强度及氯离子渗透性能。结果表明：无论标准养护还是自然养护，高吸水树脂的掺加均降低了混凝土早期强度，但当高吸水树脂掺量为1kg/m3时可提高混凝土后期强度，且提升幅度对低水胶比混凝土更明显。在盐渍土腐蚀环境中，普通混凝土强度先上升后下降，而内养护混凝土强度先下降后上升。高吸水树脂能够延缓混凝土抗压强度下降的速率，提升混凝土抗氯离子渗透能力。

高吸水树脂；内养护混凝土；抗压强度；盐渍土；氯离子渗透

Abstract: The compressive strength and chloride ion penetration of concrete exposed to saline soil for different corrosion age were tested. The inner curing concrete was prepared with super absorbent polymer (SAP) and cured in standard condition and summer natural environment. Experimental results show that the early strength of inner curing concrete decreases whether in standard curing or in natural curing environment. However, the compressive strength of concrete incorporating with 1kg/m3SAP increases in the later curing age, and the improving influence of SAP on compressive strength of concrete in later age is more remarkable for low water-binder ratio concrete than high water-binder ratio concrete. In saline soil environment, the compressive strength of plain concrete appears a trend of rise first then fall. However, the compressive strength of concrete incorporated with SAP decreases firstly, and then increases with corrosion age. The time of compressive strength decline point of concrete in saline soil was delayed, and the chloride penetration resistance capacity of inner curing concrete is improved due to the addition of SAP.

Keywords: super absorbent polymer (SAP)；internal curing concrete; compressive strength；saline soil；chloride ion penetration

盐渍土地区普遍存在高风速、低湿度、强腐蚀特点，降低混凝土水胶比可有效提升混凝土的抗腐蚀能力。一旦这类混凝土中胶凝材料、尤其是水泥用量增加，混凝土收缩将随之增加，甚至其早期自收缩占到28d总收缩变形的50%以上。加之盐渍土地区的高风、低湿影响，混凝土因自收缩和干燥收缩而导致的开裂问题时有发生。因此通过内养护，即以高吸水树脂来为混凝土内部提供水源来减少高性能混凝土的收缩成为研究的热点[1]。高吸水性树脂(SAP)是一种强亲水性的高分子化合物。由于SAP分子结构中存在大量的羟基、羧基及氨基等强亲水基因,因此，SAP具有极高的吸收水分的能力，有时吸收水的重量可以超过其自身重量的500倍[2-3]。……