为探究羟基纤维素对预崩解炭质泥岩工程特性的改良效果,开展了无侧限抗压强度、干湿循环以及理化特性的试验,以分析掺量、养护时间、干湿循环次数对预崩解炭质泥岩力学和理化特性的影响,并结合扫描电子显微镜(scanning electron microscope,SEM)技术揭示了羟基纤维素改良预崩解炭质泥岩的微观机制.结果表明:在养护时间相同的情况下,改良后的预崩解炭质泥岩的无侧限抗压强度随羟基纤维素掺量的增加呈现出先增大后减小的趋势,且当掺量为4%时,其无侧限抗压强度达到最大值;当羟基纤维素的掺量保持不变时,随着养护时间的增加,改良后的预崩解炭质泥岩的无侧限抗压强度也随之增加,并在养护14 d后趋于稳定;在干湿循环作用下,经羟基纤维素改良后的预崩解炭质泥岩的无侧限抗压强度变化符合指数函数规律;改良后的预崩解炭质泥岩的pH基本保持不变,而TDS值、电导率及盐度均有所降低;羟基纤维素主要通过胶结颗粒和填充孔隙的方式来增强预崩解炭质泥岩的力学性能.
Engineering properties of hydroxycellulose modified disintegrated carbonaceous mudstone
To investigate the engineering properties of hydroxycellulose modified disintegrated carbonaceous mudstone,this study conducted tests on its unconfined compressive strength,properties under dry and wet cycles,and physical and chemical properties.The effects of dosage,curing time,and the number of dry and wet cycles on the mechanical,physical,and chemical properties of disintegrated carbonaceous mudstone were analyzed,and the micromechanisms of hydroxycellulose modified disintegrated carbonaceous mudstone were revealed with the help of a scanning electron microscope(SEM).The unconfined compressive strength of modified disintegrated carbonaceous mudstone showed a tendency to increase first and then decrease with the increase in hydroxycellulose dosage under fixed curing time.It reached the maximum when the dosage was 4%.When the dosage of hydroxycellulose kept unchanged,the unconfined compressive strength of modified disintegrated carbonaceous mudstone increased with the increase in curing time and tended to level off after curing for 14 d.The unconfined compressive strength of hydroxycellulose modified disintegrated carbonaceous mudstone conformed to the trend of the exponential function.The pH of modified disintegrated carbonaceous mudstone remained unchanged,while its TDS value,conductivity,and salinity decreased.Hydroxycellulose enhances the mechanical properties of disintegrated carbonaceous mudstone mainly by cementing particles and filling pores.