摘要
高海拔寒冷地区坝工混凝土分层浇筑时坯层层间粗糙度评价与结合质量控制一直是施工管控薄弱点,为此,尝试采用3D激光扫描并联合多指标评价主成分分析法,构建粗糙度综合评分F值,对施工坯层面粗糙度进行量化评定;并针对高海拔寒冷地区低温干燥环境特点,分析了不同浇筑坯层间歇时间和层面粗糙度的量化指标对混凝土层间结合性能的影响。结果表明,混凝土试样层面F值最大的是平均凿毛深度4.5 mm糙面,其层面粘结劈拉强度最高;低温干燥环境(温度5℃、湿度30%)明显影响层面粘结性能,劈拉强度与整浇混凝土强度同比衰减10%左右;且层面粘结劈拉强度与间歇时间呈典型负相关性。
The evaluation and quality control of slab interlayer roughness during the layered pouring of concrete in high altitude cold areas have always been weak points of construction control.Therefore,3 D laser scanning combined with multi-index evaluation principal component analysis was used to construct a comprehensive roughness score F value to quantitatively evaluate the roughness of slab layer.According to the characteristics of low temperature and dry environment in high altitude cold area,the impact of different quantitative indexes of slab intermittent time and layer roughness on the interlayer bonding property of concrete was analyzed.The results show that the surface F value of the concrete sample is the highest in the rough surface with an average chisel depth of 4.5 mm,and the bond tensile strength is the highest in the surface.Low temperature drying environment(temperature 5℃,humidity 30%)obviously affects the layer bond performance,and the splitting tensile strength and the strength of the whole cast concrete decrease about 10%year-on-year.There is a typical negative correlation between the splicing strength and the intermittent time.
作者
李亚鹏
田正宏
孙啸
马元山
LI Ya-peng;TIAN Zheng-hong;SUN Xiao;MA Yuan-shan(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China)
出处
《水电能源科学》
北大核心
2022年第4期99-103,共5页
Water Resources and Power
关键词
水工混凝土
层间结合
粗糙度F值
间歇时间
低温干燥
hydraulic concrete
interlayer bonding
F value of roughness
intermittent time
low temperature drying
