Test Study On The Performance Of Phosphogypsum Lime-fly Ash Mixture Material

With development of China's society and economy,low cost road,ecological environment construction and resource recycling have become the focus of present research.As a side product of phosphorous chemicals industry,the ardealite not only occupies land resource but also seriously pollutes the environment.This thesis mainly researched how to apply the ardealite in road sub-base and realize resource recycling.Sub-base compound mixed with ardealite is troubled by scarce ardealite amount and poor strength in early stage.This thesis carried out relevant test research through material retrieval,laboratory test,and test analysis.The thesis determined the proportioning of three ardealite-lime ash mixtures by combining existing researches according to project cases and their later performance.With respect to various indicators of ardealite-lime ash mixtures,the thesis conducted mechanical performance test,air shrinkage and thermal contraction test,as well as water stability performance test.The test outcomes indicated,with extension of soaking time,the strength was weakened and the erosion amount was increased in unit time.Concerning 1:1 with ardealite proportioned to fly ash,this research carried out fatigue test.The test outcome showed,with increase of stress ratio,the load action times was reduced.The air shrinkage test proved no certain relationship between strain and water loss ratio.the temperature contraction test proved the influence of both phosphogypsum and fly ash is greater than the effect of temperature.both the strength and modulus can meet requirements of the present standard.Outcomes of this research indicated ardealite-lime ash mixtures should be tested in terms of their ardealite amount,mixture design,mechanical property,and contraction property and water stability before being used in road sub-base,so as to guarantee road performance of the sub-base.This research offered theoretical guidance to application of ardealite-lime ash mixtures,showing excellent social economic benefit and certain engineering reference value.