摘要
水利工程中,多孔混凝土的孔隙结构有利于土壤与水体的物质交换,是一种环境友好型混凝土。为了研究多孔混凝土抗冲刷性能的影响因素及破坏机理,采用正交试验法,利用自行设计的水循环装置,依据《水工(常规)模型试验规程》(SL155-2012)模拟自然的河道环境对多孔混凝土进行冲刷试验,探讨孔隙率、水灰比、掺合料对多孔混凝土抗冲刷性能的影响及多孔混凝土的冲刷破坏机理。试验结果表明:随着孔隙率的增大,多孔混凝土的抗冲刷性能呈现增强的趋势,孔隙率20%的多孔混凝土质量损失率2.91%,孔隙率25%的多孔混凝土质量损失率为1.6%,孔隙率30%的多孔混凝土质量损失率1.4%;水灰比增大多孔混凝土的质量损失率也随之增大,水灰比0.24的多孔混凝土质量损失率1.52%,水灰比0.26的多孔混凝土质量损失率2.39%,水灰比0.28的多孔混凝土质量损失率2.95%,胶结材料剥落现象频繁出现;掺合料对多孔混凝土抗冲刷性能的影响主要取决于其颗粒级配与活性大小,在粉煤灰、硅灰、矿渣这3种掺合料中,硅灰的活性最强且颗粒级配均匀,添加硅灰的多孔混凝土质量损失率为2.03%矿渣活性稍弱,添加矿渣的多孔混凝土质量损失率为2.5%,粉煤灰的活性最低,添加粉煤灰的多孔混凝土质量损失率为2.91%。水力冲刷破坏的主要原因是在水流的反复冲刷下,多孔混凝土内部的裂缝扩展导致界面过渡区破坏,混凝土开裂,骨料脱落,混凝土失去稳定状态。
In water conservancy engineering, porous concrete is a kind of environment-friendly concrete, which is beneficial to the material exchange between soil and water. In order to study the influence factors and failure mechanism of porous concrete’s anti-scour performance, the orthogonal test method was adopted, and the self-designed water circulation device was used,according to the code for hydraulic(conventional) model test(sl155-2012). The scour test of porous concrete was carried out to simulate the natural river environment, the influence of porosity, water cement ratio and admixture on the scour resistance of porous concrete and the scour failure mechanism of porous concrete were discussed. The results indicated that, the anti-scour performance of porous concrete showed an increasing trend with the increase of porosity. The mass loss rate of porous concrete with 20% porosity was 2.91%, the mass loss rate of porous concrete with 25% porosity was 1.6%, and the mass loss rate of porous concrete with 30% porosity was 1.4%. The mass loss rate of porous concrete increased with the increase of water cement ratio. The mass loss rate of porous concrete with 0.24 water cement ratio was 1.52%, and these were 2.39% and 2.95% with0.26 and 0.28 water cement ratio. And the cement peeling occurs frequently. The main reason for the failure of hydraulic erosion was that under the repeated erosion of water flow, the crack expansion in the porous concrete leads to the failure of the interface transition zone, the concrete cracking, the aggregate falling off and the concrete losing its stable state.
作者
闫滨
张博
闫胜利
王宏伟
苗迎雪
YAN Bin;ZHANG Bo;YAN Sheng-li;WANG Hong-wei;MIAO Ying-xue(College of Water Conservancy,Shenyang Agricultural University,Shenyang 110161,China;Water Bureau of Chaoyang County,Chaoyang Liaoning 122000,China;Wulanbai Water Conservancy Service Station,Lingyuan Liaoning 122505,China)
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2020年第2期162-168,共7页
Journal of Shenyang Agricultural University
基金
辽宁省自然科学基金项目(2019-ZD-0719)。
关键词
多孔混凝土
抗冲刷性能
孔隙率
水灰比
掺合料
porous concrete
scour resistance
porosity
water cement ratio
admixture
