超高掺量粉煤灰大坝混凝土早龄期抗裂性研究  

Cracking resistance behaviors of ultra-high volume fly ash dam concrete at early age

作　　者：赵志方[1] 李超[1] 张振宇 王卫仑 周厚贵 

机构地区：[1]浙江工业大学建筑工程学院,杭州310014 [2]葛洲坝集团试验检测有限公司,湖北宜昌443002 [3]广东省滨海土木工程耐久性重点实验室,广东深圳518060 [4]中国能源建设集团有限公司,北京100022

出　　处：《水力发电学报》2016年第7期112-119,共8页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金(51479178);浙江省自然科学基金(LY14E090006);广东省滨海土木工程耐久性重点实验室开放基金(GDDCE14-01;GDDCE15-01);中国能源建设集团科技项目(CEEC12-KJ02)

摘　　要：为解决传统的大坝混凝土早龄期热裂性能评价方法的不足,综合考虑混凝土的温度历程、约束、变形和应力的发展,采用温度–应力试验技术,从整体论出发研究粉煤灰掺量分别为35%(基准)和80%(超高掺)两种非碾压型常态大坝混凝土的早龄期抗裂性能。结果表明:超高掺混凝土水化温升低,比基准混凝土的开裂温度低、开裂温降大,水化硬化过程中热膨胀系数较小,而受拉徐变度较大,早龄期抗开裂能力强。超高掺混凝土是具有发展前景的绿色高性能大坝混凝土。This study investigates cracking resistance behaviors of ultra-high volume fly ash conventional dam concrete （UHVFACDC） at early age using a temperature-stress testing machine （TSTM）, with a comprehensive consideration of temperature history, constraint, deformation and stress of concrete from the prospective of wholism to overcome the deficiency in the traditional methods of thermal cracking property evaluation of concrete at early age. The experimental results show that in comparison with the reference concrete, this fly ash concrete has lower hydration temperature rise, and cracking temperature and its cracking temperature drop is larger. And during hardening, it manifests a smaller coefficient of thermal expansion and a higher degree of tensile creep. All this indicates that UHVFACDC of great early- age cracking resistance is a promising type of green high-performance dam concrete.

关 键 词：超高掺粉煤灰混凝土 温度-应力试验 早龄期 抗裂性 水工大坝 

分 类 号：TU528[建筑科学—建筑技术科学]