Ferronickel slag is a general industrial solid waste,which can be directly used as roadbed filler after improvement,but its dynamic characteristics are still worthy of further study.Firstly,the grading characteristics of pure ferronickel slag were analyzed by screening test,and an improved method of adding clay was proposed to determine the optimal water content and clay content.Secondly,the dynamic triaxial test of ferronickel slag-clay was carried out,and the dynamic backbone curve and dynamic elastic modulus under different clay content,compaction degree and confining pressure were obtained.Lastly,through in-situ tests and theoretical calculations of the ferronickel slag subgrade,the settlement values of the lower embankment during operation period were obtained.The results show that the pure ferronickel slag is gravel soil with poor gradation,and the maximum dry density of the sample with 35％clay content and 9％water content is the largest.With the increase of clay content,the porosity between ferronickel slag and clay particles decreases,and the corresponding dynamic strength and dynamic elastic modulus increase first and then decrease.When the clay content is 35％,the dynamic strength and dynamic elastic modulus are the largest.The greater the confining pressure and degree of compaction,the stronger the interaction between ferronickel slag and clay,and the greater the dynamic strength and dynamic elastic modulus.Based on Hardin-Drnevich model and negative power law function,the dynamic stress-dynamic strain fitting relationship and dynamic elastic modulus attenuation model of ferronickel slag-clay were established.The relationship between fitting parameters and clay content,compaction degree and confining pressure was obtained by regression,and its rationality was verified by experimental data.During the operation period,the settlement of the ferronickel slag-clay embankment is small,which meets the design requirements of the subgrade.
关键词
路基工程/动弹性模量/动三轴试验/镍铁渣/动骨干曲线
Key words
subgrade engineering/dynamic modulus of elasticity/dynamic triaxial test/ferronick-el slag/dynamic shaft curve
维普
万方数据