减水剂过掺对C30混凝土性能影响

Study on the performance of superplasticizer mixed C30 concrete

以C30自密实混凝土为研究对象,研究聚羧酸高效减水剂、萘系减水剂、木钠减水剂过掺对其新拌性能、力学性能和耐久性能的影响。试验结果表明:3种减水剂的过掺均会使C30自密实混凝土坍落扩展度增加、含气量降低、凝结时间延长、混凝土立方抗压强度、28 d轴心抗压强度、28 d弹性模量降低、耐久性变差。此外,对混凝土28 d抗折强度的影响则因减水剂种类而异。

It investigated the effects of the over-dosage ofpolycarboxylate superplasticizer,naphthalene superplasticizer sodium and the sodium lignosulphonate on the performance of fresh concrete, mechanical properties and durability of C30 self-compacting concrete.The results showed that the over-dosage of all the three water reducing admixtures would increase the flowability of the fresh concrete, reduce the air content,prolong the setting time.The over-dosage of the water reducing admixtures would also reduce the compressive strength of the axial compressive strength and the modulus of elasticity of concrete curing for 28 day.In addition, the flexural strengths of concrete curing for 28 days were different due to the types of water-reducing agent.