Deng Yongjing, Ma Guanguo, Sun Zhenjiao, Gao Kang, Ma Hui, Song Tingting, Jia Wenfeng
College of Mining and Safety Engineering, Shandong University of Science and Technology, Qingdao 266590, China.
School of Safety and Engineering, China University of Mining and Technology, Xuzhou 221116, China.
Materials (Basel). 2024 Dec 23;17(24):6298. doi: 10.3390/ma17246298.
Aiming at the problems of collapse, deformation, and displacement in the concrete paving of roadway floors, this paper adopts the way of adding alkali-free accelerators to the concrete on both sides, through mechanical analysis, single factor experiment, orthogonal experiment, and polynomial fitting method, and determines the relevant parameters of concrete and accelerators in the sliding form paving of roadway floor from two aspects of paving material and size. The results show that the FSA-AF alkali-free liquid accelerator is more suitable for roadway floor paving than the J85 powder accelerator. When the FSA-AF accelerator dosage reaches 8%, the decreasing trend of initial setting time curve tends to be flat. The deformation resistance of concrete containing accelerator is positively correlated with the dosage of the accelerator. Concrete side pressure is positively correlated with pavement paving height. The FSA-AF accelerator can reduce the compressive strength of concrete; the compressive strength and retention rate of concrete at all ages are the highest when the dosage of FSA-AF is 7%. A water-cement ratio of 0.4 and a 9% dosage of accelerator are the optimal combination to meet the four evaluation indexes. According to the width estimation formula, the width of the side concrete should be set to 14 cm.
针对巷道底板混凝土浇筑中出现的坍塌、变形和位移问题,本文采用在两侧混凝土中添加无碱速凝剂的方式,通过力学分析、单因素试验、正交试验和多项式拟合方法,从摊铺材料和尺寸两个方面确定了巷道底板滑模摊铺中混凝土及速凝剂的相关参数。结果表明,FSA-AF无碱液体速凝剂比J85粉状速凝剂更适合巷道底板摊铺。当FSA-AF速凝剂用量达到8%时,初凝时间曲线下降趋势趋于平缓。含速凝剂混凝土的抗变形能力与速凝剂用量呈正相关。混凝土侧压力与路面摊铺高度呈正相关。FSA-AF速凝剂会降低混凝土的抗压强度;当FSA-AF用量为7%时,混凝土各龄期的抗压强度和保留率最高。水灰比为0.4、速凝剂用量为9%是满足四项评价指标的最佳组合。根据宽度估算公式,侧面混凝土宽度应设置为14cm。