混凝土
混凝土
혼응토
CONCRETE
2014年
2期
5-8
,共4页
素混凝土%冻融循环%抗压强度%质量损失
素混凝土%凍融循環%抗壓彊度%質量損失
소혼응토%동융순배%항압강도%질량손실
plain concrete%freeze-thaw cycle%compressive strength%mass lost
为了进一步研究约束混凝土和无约束混凝土的抗冻性能差异，以约束混凝土模型为参照，制作相同配合比的素混凝土立方体块并在相同条件下进行0、20、40、60、100、120次的冻融腐蚀试验。主要分析冻融腐蚀下素混凝土试块抗压强度，质量损失以及吸水率等性能随冻融次数的变化规律，并建立素混凝土抗压强度和质量损失冻融损伤预测模型。试验结果表明：随冻融循环次数增加，素混凝土的抗压强度呈抛物线下降，干燥质量和饱水质量呈线性下降，而吸水率则呈双折线下降。从材料层次方面，粉煤灰对混凝土抗压强度损失，质量损失率和吸水率影响较大，而水灰比对以上指标影响较小。掺15%粉煤灰的抗压强度损失比不掺粉煤灰的混凝土大约20%~30%；质量损失率比不掺粉煤灰的大5%~6%，粉煤灰不利于抗冻性能。相同粉煤灰含量，低水灰比抗压强度损失，质量损失率和吸水率变化比高水灰比小，使用粉煤灰混凝土时易降低水灰比。
為瞭進一步研究約束混凝土和無約束混凝土的抗凍性能差異，以約束混凝土模型為參照，製作相同配閤比的素混凝土立方體塊併在相同條件下進行0、20、40、60、100、120次的凍融腐蝕試驗。主要分析凍融腐蝕下素混凝土試塊抗壓彊度，質量損失以及吸水率等性能隨凍融次數的變化規律，併建立素混凝土抗壓彊度和質量損失凍融損傷預測模型。試驗結果錶明：隨凍融循環次數增加，素混凝土的抗壓彊度呈拋物線下降，榦燥質量和飽水質量呈線性下降，而吸水率則呈雙摺線下降。從材料層次方麵，粉煤灰對混凝土抗壓彊度損失，質量損失率和吸水率影響較大，而水灰比對以上指標影響較小。摻15%粉煤灰的抗壓彊度損失比不摻粉煤灰的混凝土大約20%~30%；質量損失率比不摻粉煤灰的大5%~6%，粉煤灰不利于抗凍性能。相同粉煤灰含量，低水灰比抗壓彊度損失，質量損失率和吸水率變化比高水灰比小，使用粉煤灰混凝土時易降低水灰比。
위료진일보연구약속혼응토화무약속혼응토적항동성능차이，이약속혼응토모형위삼조，제작상동배합비적소혼응토립방체괴병재상동조건하진행0、20、40、60、100、120차적동융부식시험。주요분석동융부식하소혼응토시괴항압강도，질량손실이급흡수솔등성능수동융차수적변화규률，병건립소혼응토항압강도화질량손실동융손상예측모형。시험결과표명：수동융순배차수증가，소혼응토적항압강도정포물선하강，간조질량화포수질량정선성하강，이흡수솔칙정쌍절선하강。종재료층차방면，분매회대혼응토항압강도손실，질량손실솔화흡수솔영향교대，이수회비대이상지표영향교소。참15%분매회적항압강도손실비불참분매회적혼응토대약20%~30%；질량손실솔비불참분매회적대5%~6%，분매회불리우항동성능。상동분매회함량，저수회비항압강도손실，질량손실솔화흡수솔변화비고수회비소，사용분매회혼응토시역강저수회비。
In order to further study the antifreeze performance difference of confined concrete and plain concrete,in confined concrete model for reference,making the same ratio of plain concrete cubic block and under the same conditions were also tested under freeze-thaw cycle of different numbers as 0,20,40,60,100 and 120 times,As the second part,mainly analyzed the compressive strength of plain concrete under freeze-thaw test,mass loss of samples and water absorption performance changing with the number of freezing and thawing,and establish the freeze-thaw damage prediction model of concrete compressive strength and mass loss ratio.Experiment showed that with the increase of freeze-thaw cycles,the compressive strength of plain concrete decreased parabola,drying quality and full water mass linearly decreased,while water absorption decreased by double line.From the aspects of material level,fly ash had a greater influence on the loss of concrete compressive strength,mass loss rate and water absorption,while water cement ratio had little influence on the above indicators.The loss of compressive strength of mixing 15%fly ash concrete was about 20%to 30%higher than mixing no fly ash concrete;Mass loss rate was about 5%to 6%larger than not mixing fly ash ,fly ash is not conducive to the antifreeze performance of concrete.As the same fly ash,the loss of compressive strength,mass and bibulous rate in low water-cement ratio concrete changed lager than high water cement ratio.When using fly ash concrete,it is easy to reduce the water cement ratio.
