摘要
为了研究高强沙漠砂混凝土高温后的力学性能,采用室温、200℃,400℃,600℃,800℃和900℃六个温度等级,利用自然冷却方式,通过正交试验,研究水胶比,粉煤灰掺量和沙漠砂替代率对高强沙漠砂混凝土高温后抗压强度的影响,对高强沙漠砂混凝土试件高温后的外观颜色变化进行了观察,分析了高温后高强沙漠砂混凝土试件的质量变化。试验研究表明:与室温下高强沙漠砂混凝土抗压强度相比,200℃高温后高强沙漠砂混凝土强度有所降低,在400℃至600℃高温后抗压强度有所升高,之后随着温度的升高抗压强度逐渐降低;随着温度升高,高强沙漠砂混凝土外观颜色由深变浅,质量损失率呈现逐渐增加趋势。通过方差分析和极差分析,给出了高强沙漠砂混凝土最佳配合比,为高强沙漠砂混凝土的工程应用提供借鉴和指导。
In order to research the mechanical properties of high strength desert sand concrete,an orthogonal experiment was designed to study the influence of water cement ratio,fly ash dosage and desert sand replacement rate on the compressive strength of high strength desert sand concrete after high temperature in natural cooling.Different temperatures such as room temperature,200 ℃,400℃,600 ℃,800 ℃ and 900 ℃ were adopted in the experiment.The appearance of high strength desert sand concrete specimens after high temperature was observed.The quality changes of high strength desert sand concrete specimens after high temperature were also analyzed.Experimental results show that compared with the compressive strength of high strength desert sand concrete under room temperature,the compressive strength of high strength desert sand concrete after 200 ℃ decreases somewhat.When the temperature ranges from 400 ℃ to 600 ℃,the compressive strength of high strength desert sand concrete after high temperature increases to some extent.When the temperature is above 600 ℃,the compressive strength of high strength desert sand concrete after high temperature decreases gradually with the temperature.With the increase of temperature,the color of high strength desert sand concrete specimen changes from dark to light.The mass loss rate increasesgradually.The optimum mixture ratio of high strength desert sand concrete is obtained by means of range analysis and variance analysis,which provides guidance for the engineering application of desert sand.
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2015年第1期112-120,共9页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金资助项目(11162015
51368048)
关键词
高强混凝土
毛乌素沙漠砂
正交试验
高温
自然冷却
high strength concrete
Mu Us desert sand
orthogonal experiment
high temperature
natural cooling
