刘香+吴成龙+许有俊+孙国栋+陈彬

摘要：依托包钢新体系2 250 mm热轧车间的地基处理工程对混合料的力学特性进行研究；借助大型直剪仪对不同围压和含水率的混合料进行直剪试验，分析了混合料在不同条件下的抗剪强度、力学参数以及从混合料剪切“翻滚跳跃”现象的角度对相应的剪应力剪切位移关系曲线上下波动情况进行分析；通过线性回归分析得到含水率与粘结力和内摩擦角的关系曲线。结果表明：当含水率相同时，随着法向应力的增加，混合料的抗剪强度峰值逐渐增大；相同法向应力作用下，随着含水率的增加，混合料的抗剪强度逐渐降低；随着含水率的增加，粘结力和内摩擦角逐渐降低，并且含水率的变化对粘结力的影响程度较内摩擦角大；当剪切位移处于试样长度的1/60～1/10时，剪切“翻滚跳跃”现象最为明显，相应的剪应力剪切位移曲线所出现的上下波动幅度也最大。

关键词：高炉矿渣；粉煤灰；大型直剪试验；力学特性

中图分类号：TU521.4文献标志码：A

Research on Mechanical Properties of Blast Furnance Slag Fly Ash

Mixture Based on Largescale Direct Shear ExperimentLIU Xiang1， WU Chenglong1， XU Youjun1，SUN Guodong2，3， CHEN Bin1

（1. College of Architecture and Civil Engineering， Inner Mongolia University of Science & Technology， Baotou

014010， Inner Mongolia， China； 2. Key Laboratory of Hydraulic and Waterway Engineering of Ministry of

Education， Chongqing Jiaotong University， Chongqing 400074， China； 3. National Engineering Research

Center for Inland Waterway Regulation， Chongqing Jiaotong University， Chongqing 400074， China）Abstract： The mechanical properties of mixture were studied based on a new system of Baotou Steel 2 250 mm hotrolling workshop ground treatment engineering. By means of largescale direct shear apparatus， direct shear tests of mixture with different confining pressures and moisture contents were carried out. The shear strength and mechanical parameters of mixture under different conditions were analyzed. The fluctuations of shear stressshear displacement curves were analyzed from perspective of shear “rolljump” phenomenon of mixture. The relationship curves of moisture content， cohesive force and internal friction angle were obtained through linear regression analysis. The results show that the peak value of shear strength of mixture increases gradually with increase of normal stress when moisture content is the same. Under the same normal stress，shear strength of mixture decreases gradually with increase of moisture content. The cohesive force and internal friction angle decrease gradually with increase of water content. The impact of moisture content change on cohesive force is greater than internal friction angle. When the shear displacement is 1/601/10 of specimen length， shear “rolljump” phenomenon is most obvious， and the fluctuations of shear stressshear displacement curves are greatest.

Key words： blast furnace slag； fly ash； largescale direct shear experiment； mechanical property

0引言

高炉矿渣是在高炉冶炼生铁过程中产生的一种固体废弃物，其主要化学成分为SiO2，Al2O3，CaO，MgO，MnO，FeO等，其中CaO，SiO2，Al2O3占质量的90%以上。由于炼铁原料的成分、种类以及冶炼技术的差异，使得高炉矿渣的组成不尽相同。高炉矿渣按冶炼生铁的品种可分为铸造生铁矿渣、炼钢生铁矿渣和特种生铁矿渣，按照高炉矿渣的碱性率可分为碱性矿渣、中性矿渣和酸性矿渣。粉煤灰一般是指燃煤电厂从烟道气体中收集的细灰，其主要组成为O，Si，Al，Fe等元素构成的氧化物。……