Study On Construction Technology Of Transport Road In Open Pit Mine Based On Fly Ash And Slag Geopolymer

Open-pit mining is one of the main mining methods of coal.There are many problems in open-pit coal mine,including the cost,environment and safety problems caused by the simple construction process of transportation road.In addition,the industrial circle with the mine as the center discards a large amount of waste to pollute the environment,which can not be effectively solved.In this paper,fly ash and slag from industrial solid waste will be used as raw materials to build open pit mine transportation road,which provides a new idea for the construction of environmentfriendly mining ecosphere with green sustainable development as the center.This paper analyzes the classification and basic structure and function of open-pit road,and probes into the mechanical action of the road and the stress characteristics of the road in different driving conditions of trucks.Compared with the ordinary highway,the open-pit mine transport road generally has a certain dip Angle,the pavement bears greater pressure,and the transport intensity and service life are much lower than the ordinary civil highway.Therefore,the open-pit mine transport road has higher requirements on the strength of materials and lower requirements on durability.The influence of sodium silicate modulus,sodium silicate content and slag/fly ash ratio on the uniaxial compressive strength of the flyash-slag geopolymer was studied by adjusting the content of raw materials.The experimental results show that the stressstrain curve of the fly-ash slag geopolymer under uniaxial compression is similar to that of the common rock,which can be divided into four stages: compaction stage,elastic stage,molding stage and residual strength.When slag content is too high,the content of Al2O3 and Si O2 will decrease,and the polymerization rate of geopolymer will be reduced.Therefore,with the increase of slag proportion,the peak strength and peak strain of sample will first increase and then decrease.Due to the high requirement of alkali content in the polymerization process of geopolymer materials,the lower the sodium silicate modulus and the higher the sodium silicate content of the samples,the stronger the mechanical properties,the greater the peak strength and peak strain.At the same time,this paper studies the road quality control technology in the process of geompolymer road construction: the mixing of powder and activator is the key link in the construction,and the uniformity of mixing directly affects the strength of the road.The ideal mixing condition is that the powder,gravel aggregate and activator are completely and evenly mixed,and there is no local high or low strength after the formation of road strength.In addition,the water content of the original road should be considered when designing the engineering mix ratio,which will play a key role in ensuring the overall stability and controllability of the road.The engineering test results show that the rapid road construction technology with cold regeneration as the core can match the production schedule of open pit mine,and no structural damage occurs in the rolling test 7 days after the completion of road construction.The average strength of the pavement material is about 10 MPa in the insitu sampling strength test of the road.Geoppolymer as a road construction material can meet the requirements of mine transport road strength use,through cold re-vitality construction of mine road can be opened to traffic within 7 days,and has the characteristics of suppressing road dust and consumption of mine solid waste,is expected to be applied on the scale of new mine environmental protection,efficient and economic road materials.