煤矸石掺量对混凝土耐久性影响研究

Experimental study on the spontaneous combustion coal gangue concrete

主要研究煤矸石掺量对混凝土性能的影响。试验选用煤矸石按照20％、40％、60％、80％、100％的掺量取代碎石制备 C30、C40的混凝土，探索研究煤矸石掺量对混凝土强度、抗冻性、抗渗性和碳化性能的影响，并对煤矸石的碱活性进行验证。试验结果证明，煤矸石的掺量大小对 C30混凝土和煤矸石掺量在60％以下时的 C40混凝土强度影响不大；但是当煤矸石掺量在60％以上时，C40混凝土强度明显降低；混凝土碳化试验结果表明，7 d 龄期碳化深度无明显变化，而随着煤矸石掺量的增加28 d 龄期混凝土碳化深度增大了11～17 mm；混凝土抗渗性能随着煤矸石掺量的增加渗水高度最大增加35 mm，电通量增大到普通混凝土的1．5～1．7倍。煤矸石混凝土的碱活性测试结果显示，华龙集团的煤矸石不具备碱活性。

Concrete samples（strength grade is C30 and C40）were prepared,of which the gravel was replaced by slag,the slag content is 20%,40%,60%,80%and 100% respectively.The effect of slag content on compressive strength,freezing resistance,carbonization re-sistance and anti - permeability of concrete was studied,alkali reactivity of slag was also tested.The results show that slag content has no distinct effect to the compressive strength of C30 concrete,and it can hardly effect the compressive strength of C40 concrete as the con-tent is below 60%.As the slag content is more than 60%,compressive strength of C40 concrete decreases obviously.The 7 d concrete carbonation depth is stable,as the curing age is 28 d,carbonation depth of the samples increase by 11～17 mm.With the increasing of water penetration height rise to 35 mm,the infiltration capacity of Cl - increases about 1.5～1.7 times.Slag make from Hualong Industry Group has no alkali reactivity.