| There are many iron ores in Ma’anshan City and surrounding areas in Anhui,and a large amount of iron tailings will be produced every year.Iron tailings are waste after iron ore beneficiation.Due to the lack of effective treatment methods and utilization methods,a large amount of iron tailings The accumulation of mines not only occupies land and blocks rivers,but also causes pollution and damage to the environment,but also has an adverse impact on human health.In recent years,with the increase of national environmental protection,the exploitation of natural gravel resources has been restricted.The shortage of sand and gravel resources has intensified the contradiction between the supply and demand of traditional road construction materials,resulting in the increasing status of road construction costs.If iron tailings can be used as road base and bottom base materials in road engineering,it can not only reduce the demand for sand and gravel resources in road engineering,alleviate the shortage of sand and gravel resources,but also effectively solve the massive accumulation of iron tailings.A series of problems caused.Based on the above status quo,this paper combines indoor test data,finite element software simulation analysis,test road construction and later detection results,etc.to study the road performance of modified iron tailings and modified iron tailings stabilized crushed stone To explore ways to apply modified iron tailings mixture to road base,the main research contents are as follows:1.The strength formation mechanism of the modified iron tailings mixture was studied through theoretical analysis and micro-testing,and the influence of the modified iron tailings cementing material on its strength formation was analyzed.The following conclusions are drawn: The strength of the modified iron tailings mixture is mainly composed of cohesion and friction resistance.2.Carried out laboratory test research on modified iron tailings,mainly including raw material physical and chemical properties test,unconfined compressive strength test,indirect tensile strength(split strength)test,rebound modulus test,freeze-thaw test,according to The conclusions of the above test results are as follows: the physical and chemical properties of iron tailings and modified iron tailings cement materials meet the requirements of relevant technical specifications and can be used in road engineering;the unconfined compression of modified iron tailings The strength,indirect tensile strength(crack strength)and rebound modulus are all higher than the corresponding technical indicators of traditional inorganic binder stabilization materials;the main influencing factors of the mechanical properties of modified iron tailings are iron tailings Self-gradation and dosage of gelling material.3.Conducted laboratory tests on modified iron tailings and modified iron tailings stabilized crushed stone,mainly including physical and chemical properties of raw materials,unconfined compressive strength test,indirect tensile strength(split strength)test,rebound The modulus test and freeze-thaw test result in the following conclusions: By adjusting the gradation of the two and the content of the cement material,the unconfined compressive strength,splitting strength and other technical indicators are sufficient to meet the requirements of the specification,and The road performance of the stabilized material with the traditional inorganic binder is similar or even better than the traditional material.Combined with skeleton filling theory,the effects of gradation and filling degree on the mechanical properties of modified iron tailings stabilized crushed stone were analyzed and studied.And use ABAQUS finite element software to simulate the analysis of the unconfined compressive strength test process of the two,to provide a scientific basis for the rationality of the experimental research results.4.The mechanical properties of modified iron tailings and modified iron tailings stabilized crushed stone were studied by finite element simulation technology.The ABAQUS finite element software was used to establish the unconfined compression specimen models of the two materials,respectively.Simulation analysis of unconfined compressive strength test process.According to the comparative analysis of the simulation calculation results and the test data,the research conclusion that the simulation calculation results and the test data are in agreement is obtained,which provides a scientific basis for the rationality of the research results.5.Paving the test road,comprehensive evaluation of the test road through theoretical analysis,on-site test research,test results in the later stage of the test road and economic benefit analysis.The results show that the indicators of the test road meet the technical requirements of the relevant specifications,and the application of modified iron tailings mixture to the road base can effectively save engineering costs. |
