Study On Mechanical Properties Of Coal Gangue Mixture In Pavement Base

With the current rapid development of social economy,the demand for various raw materials in all walks of life is increasing year by year.Therefore,coal enterprises,as raw materials for relevant industries,are also moving towards environmental protection and recycling.In the process of coal mining and coal washing,various wastes will be discharged into nature,of which the largest proportion and the most widely occupied solid waste is coal gangue.A large amount of coal gangue is accumulated for a long time.If it is not handled properly,it will cause serious environmental pollution to the local and surrounding environment.However,if coal gangue is used properly,it can be used in a variety of industries.In the way of comprehensive utilization of coal gangue,mixing lime,fly ash,cement and coal gangue into road base materials can not only effectively use a large amount of accumulated coal gangue,but also reduce its pollution to the surrounding environment and contribute to the local economic development.It is an important link to realize sustainable development in China.In order to design coal gangue mixture suitable for different grades of highway pavement base,the mechanical properties of raw materials and mixtures were experimentally studied in this thesis.According to relevant specifications,taking the coal gangue produced in a mining area in Handan as the main research object,the coal gangue is a "red gangue" that has completely spontaneous combustion.Combined with the locally supplied fly ash,lime and cement,the coal gangue mixture is prepared in a certain proportion.The material properties of various raw materials are tested,and the results show that the surface properties can meet the requirements.Firstly,the mixture mix proportion is designed.Considering the economic aspects and applicable to the pavement base of different highway grades,three groups of coal gangue lime fly ash mixture mix proportion with different strength are designed.On the basis of two groups of coal gangue lime fly ash mixture mix proportion,cement is added to design two groups of coal gangue cement stabilized mixture mix proportion with higher strength,Three tests were carried out on the mix proportion of five groups of coal gangue mixtures: unconfined compressive strength test,splitting strength test and rebound modulus test.The analysis of the experimental results shows that the designed mix proportion of coal gangue mixture can meet the mechanical performance requirements of pavement base of different grades of highway.Then compare the coal gangue mixture designed in this test with other coal gangue mixtures,and analyze the reasons for the differences in various mechanical performance indexes.The results show that the coal gangue mixture designed in this test has more economic benefits,meets the performance requirements of pavement base and subbase,and provides a reference for the composition design and application of coal gangue mixture pavement base in practical engineering.