Durability and life prediction of freeze-thaw-wind erosion of channel lining concrete
LIU Wei1,2, ZOU Chunxia1*, XUE Huijun1, GUO Xiaosong1, SUN Haoran1, SONG Yuxin1
1. Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China; 2. Housing and Urban Rural Development Bureau of Dalad Banner, Ordos, Inner Mongolia 017300, China
Abstract:In order to explore the durability of channel lining concrete under adverse environmental conditions of freeze-thaw cycle and wind-sand erosion in Hetao Irrigation District, Inner Mongolia, solid waste fly ash and silica fume were used to replace part of the cement for preparing channel concrete samples. The fast freezing method and air flow sand-carrying method were used to simulate the field service environment, damage pattern of the surface erosion was observed with the help of super depth of field, and the pore structure was as well studied by nuclear magnetic resonance(NMR). The results show that the erosion of concrete by wind and sand causes serious shedding of the surface slurry, and the Yellow River water and salt ions easily enter the internal pores of the concrete. The freeze-thaw cycle accelerates the frost heaving and salt invasion, and the harmful and multi-hazard pores gradually form through cracks. The mass and dynamic elastic modulus loss is serious, which accelerates the freeze-thaw damage of the concrete. Double admixtures helps to increase the surface density, improves internal gelation, as well as the freeze-thaw resistance and freeze-thaw-wind erosion durability were significantly improved. Based on the material decay theory, the relative dynamic elastic modulus was used as the evaluation index to establish the life prediction model of freeze-thaw-wind erosion of concrete, and the calculated service life of F15S4 mixed with fly ash silica fume was 1.3 times higher than that of single fly ash. It provides a theoretical basis for the popularization and application of solid waste silica fume-fly ash in channel concrete around the irrigation area, and provides some basic research for the preparation of channel lining suitable for the special service environment of the Hetao irrigation area.
刘伟,邹春霞*,薛慧君,郭晓松,孙浩然,宋育鑫. 渠道衬砌混凝土冻融风蚀耐久性能及寿命预测[J]. 排灌机械工程学报, 2023, 41(6): 568-575.
LIU Wei,ZOU Chunxia*,XUE Huijun,GUO Xiaosong,SUN Haoran,SONG Yuxin. Durability and life prediction of freeze-thaw-wind erosion of channel lining concrete. Journal of Drainage and Irrigation Machinery Engin, 2023, 41(6): 568-575.