矿物掺合料混凝土工作性能、力学性能和抗碳化性能试验研究

发布时间：2018-06-17 02:56

本文选题：混凝土 + 碳化　；参考：《内蒙古工业大学》2013年硕士论文

【摘要】：近年来,矿物掺合料混凝土被广泛应用于工业与民用建筑中。在混凝土中掺入粉煤灰和矿粉,首先,能解决工业废料堆积对环境的污染问题。其次,矿物掺合料掺入混凝土中可以改善混凝土的工作性能、力学性能和提高混凝土的耐久性。最后,粉煤灰和矿粉掺入混凝土能减少水泥用量,降低混凝土成本。但是,近年来国内研究表明,因粉煤灰和矿粉地域的差异,造成其化学成分不同,粉煤灰和矿粉对混凝土的碳化性能影响也不尽相同。本次试验是结合前人研究理论的基础上,主要结合本地原材料,研究粉煤灰混凝土和矿粉混凝土的工作性能、力学性能和抗碳化性能。本次碳化试验所采用的是快速碳化方法,研究粉煤灰和矿粉对混凝土工作性能、力学性能及抗碳化性能的影响。试验是在C30、C40、C50混凝土中分别单掺粉煤灰和矿粉,掺量为0%,10%,20%,30%,40%。C30混凝土复掺粉煤灰和矿粉,掺10%粉煤灰和分别掺入10%,20%,30%矿粉；掺10%矿粉和分别掺入10%,20%,30%的粉煤灰。试验表明： (1)粉煤灰、矿粉的加入改善了混凝土的工作性能。粉煤灰的掺量小于30%时坍落度增大,当粉煤灰掺量增加到40%时,坍落度减小,说明粉煤灰掺量过大对混凝土工作性能无益；矿粉的掺入改善混凝土工作性能,但是,当与粉煤灰掺量相同时,工作性能比粉煤灰混凝土要差。 (2)由于粉煤灰和矿粉的活性不同,对混凝土的抗压强度影响不同。掺入粉煤灰及矿粉的早期强度(7d)与基准相比稍低。随着养护龄期的增长,掺入粉煤灰和矿粉的混凝土抗压强度均高于基准混凝土强度,中后期28d、60d混凝土强度都达到设计强度且均高于基准混凝土。粉煤灰掺量在40%时,强度比基准混凝土抗压强度高,但与掺量小于30%的相比较低,说明粉煤灰的掺量应控制在30%以内。 (3)不同强度等级的混凝土,碳化深度也是不同的。随着强度等级的提高,混凝土的抗碳化能力增强。 (4)粉煤灰混凝土碳化深度与粉煤灰的掺量成正比；矿粉混凝土与粉煤灰混凝土相比,矿粉混凝土抗碳化性能优于粉煤灰混凝土。 (5)通过经济分析得出,矿粉掺量30%时,C30、C40、C50混凝土的工作性能较好、抗压强度高、碳化深度浅,所以说,矿粉掺量在30%时矿粉混凝土经济性最高。
[Abstract]:In recent years , mineral admixture concrete has been widely used in industrial and civil buildings . Fly ash and mineral powder are mixed in concrete . First , it can solve the environmental pollution problem of industrial waste accumulation . In addition , the mineral admixture can improve the workability , mechanical property and durability of concrete .

The effect of fly ash and mineral powder on the workability , mechanical properties and carbonation resistance of concrete was studied by means of rapid carbonation .

The experimental results show that fly ash and ore powder are separately added into C30 , C40 and 50 C concrete respectively , the content is 0 % , 10 % , 20 % , 30 % , 40 % . C30 concrete is mixed with fly ash and ore powder , 10 % fly ash is added and 10 % , 20 % and 30 % mineral powder are added respectively ;
10 % of mineral powder and 10 % , 20 % and 30 % fly ash are added respectively . The test shows that :

( 1 ) The addition of fly ash and mineral powder improves the working performance of the concrete . When the content of fly ash is less than 30 % , the slump is increased . When the content of fly ash increases to 40 % , the slump decreases , indicating that the content of fly ash is too large to be beneficial to the working performance of the concrete ;
The incorporation of mineral powder improves the workability of the concrete , however , when the content of fly ash is the same , the working performance is worse than that of the fly ash concrete .

( 2 ) Due to the different activity of fly ash and mineral powder , the compressive strength of concrete is different . The compressive strength of concrete mixed with fly ash and mineral powder is slightly lower than that of reference concrete . With the increase of curing age , the compressive strength of concrete mixed with fly ash and mineral powder is higher than that of reference concrete . When the content of fly ash is 40 % , the strength is higher than that of reference concrete , but it is lower than that of reference concrete when the content of fly ash is less than 30 % , so that the content of fly ash should be controlled within 30 % .

( 3 ) The carbonation depth of the concrete with different strength grades is different . As the strength grade increases , the carbonation resistance of the concrete is enhanced .

( 4 ) the carbonation depth of fly ash concrete is proportional to the amount of fly ash ;
Compared with fly ash concrete , the anti - carbonization property of mineral powder concrete is better than that of fly ash concrete .

( 5 ) According to the economic analysis , when the content of mineral powder is 30 % , the working performance of C30 , C40 and 50 C concrete is good , the compressive strength is high , the carbonization depth is shallow , so that the mineral powder concrete has the highest economic efficiency when the content of mineral powder is 30 % .
【学位授予单位】：内蒙古工业大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU528

【参考文献】