Mohammed Bashar S, Yen Lee Yin, Haruna Sani, Seng Huat Michael Lim, Abdulkadir Isyaka, Al-Fakih Amin, Liew M S, Abdullah Zawawi Noor Amila Wan
Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar 32610, Malaysia.
Department of Civil Engineering, Bayero University Kano, 3011 Kano, Nigeria.
Materials (Basel). 2020 Aug 10;13(16):3516. doi: 10.3390/ma13163516.
This paper reports the findings of the effect of elevated temperature on the compressive strength and durability properties of crumb rubber engineered cementitious composite (CR-ECC). The CR-ECC has been tested for its compressive strength and chemical resistance test against acid and sulphate attack. Different proportions of crumb rubber (CR) in partial replacement to the fine aggregate and polyvinyl alcohol (PVA) fiber have been utilized from 0 to 5% and 0 to 2%. The experiments were designed based on a central composite design (CCD) technique of response surface methodology (RSM). After 28 days curing, the samples were preconditioned and exposed to high temperatures of 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, 800 °C, 900 °C, and 1000 °C for one hour. Although the residual compressive strength of CR-ECC was negatively affected by elevated temperature, no explosive spalling was noticed for all mixes, even at 1000 °C. Results indicated that CR-ECC experiences slight weight gain and a reduction in strength when exposed to the acidic environment. Due to the reduced permeability, CR-ECC experienced less effect when in sulphate environment. The response models were generated and validated by analysis of variance (ANOVA). The difference between adjusted R-squared and predicted R-squared values for each model was less than 0.2, and they possess at least a 95% level of confidence.
本文报道了高温对橡胶颗粒增强工程水泥基复合材料(CR-ECC)抗压强度和耐久性的影响研究结果。对CR-ECC进行了抗压强度测试以及耐酸和耐硫酸盐侵蚀的化学抗性测试。分别使用了0%至5%的橡胶颗粒(CR)替代细集料,以及0%至2%的聚乙烯醇(PVA)纤维,采用了不同的配比。实验基于响应面法(RSM)的中心复合设计(CCD)技术进行设计。养护28天后,对样品进行预处理,并分别在100℃、200℃、300℃、400℃、500℃、600℃、700℃、800℃、900℃和1000℃的高温下暴露一小时。尽管CR-ECC的残余抗压强度受到高温的负面影响,但所有混合料即使在1000℃时也未出现爆炸剥落现象。结果表明,CR-ECC在酸性环境中会出现轻微的重量增加和强度降低。由于渗透率降低,CR-ECC在硫酸盐环境中的影响较小。通过方差分析(ANOVA)生成并验证了响应模型。每个模型的调整R平方值和预测R平方值之间的差异小于0.2,且它们具有至少95%的置信水平。