| Durability is important property of concrete structure.Modified《concrete structure design codes》GB50010-2002 and《concrete construction and acceptance codes》GB50204-2002 have increased basic requirements which include measurements of prevent alkali-aggregate reaction for warranty the durability of concrete structure.From the alkali reactivity research of concrete aggregates in Urumqi and Ku'erle areas,the petrographic analysis showed the aggregates latency possess alkali reactivity. With mortar stuck detection,almost all the expansion ratio of aggregates reach to 0.104%～0.321%and greater than National Standard estimation margin 0.1%.The aggregates of these two regions have been concluded alkali reactivity.By analysis calculation of alkali quantity use in common concrete mixing proportion of this two regions,on the general situation,indicated when concrete strength equal or high to C30,the concrete alkali quantity over 3.0 kg/m~3 which is maximal alkali quantity of National Regulation.At the result,the concrete structures of Xinjiang region have severity hidden danger of alkali-aggregate reaction.On the practical situation of Urumqi and Ku'erle areas,selected industrial wastes such as pulverized coal ash,slag powder and lithium silica flour to be admixtures for restrain concrete alkali-aggregate reaction;and with differ percentage replace same quantity of cement respectively,then made concrete prism,measuring expansion ratio, according to matching curve to get lowest or suitable quantity for inhibitory effect. By contrastive analysis way,the economic analysis has been taken using industrial wastes to contain concrete alkali-aggregate reaction.It is show that the improvement of economic effect with same quantity of cement under satisfied the technical requirements. And from the research analysis,indicate using industrial wastes not only can prevent imperil of concrete alkali-aggregate reaction,but reach the favorable economic benefits and social benefits. |
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