Effect Of Recycled Glass Powder On Volume Stability And Impermeability Of Morta

Glass is widely used in many fields due to its advantages such as good light transmittance,high mechanical strength,excellent chemical and thermal stability,heat insulation,sound insulation,and aesthetics.However,excessive use of glass inevitably results in a surge of glass garbage.The traditional disposal methods of glass waste are not economical and environmental friendly,in contrast,employing recycled glass powder as partial replacement of cement in practical engineering is extremely a good choice.At present,the related researches mainly focuses on the influence of glass powder on the mechanical properties of mortar,while the research on the influence of glass powder on the impermeability of mortar has not been reported yet.In this paper,the impermeability of glass powder mortar was studied,and different mix proportions of mortar were achieved by altering the particle size(median diameter 6.63 μm,18.33 μm,30.15 μm and 49.38 μm)and content(0%–15%)of glass powder.The main research contents and results are as follows.(1)During different water-curing periods of 28,90,180 and 360 days,the reaction degree of glass powder inside the mortar was distinct..At the age of 28 days,the surface of the glass powder was relatively smooth,almost no obvious corrosion was detected.As the age reached 90 – 180 days,the reaction rate of the glass powder increased and significant corrosion was observed on the surface of the glass powder.At 360 days,the glass particles were invisible in the mortar.(2)At long age,the larger the amount of glass powder added,the less the water seepage paths inside the mortar.In terms of impermeability,the larger the amount of glass powder added,the poorer the impermeability of mortar that cured for 28 days.However,the impermeability of the mortar became better with increasing glass powder addition when the age was up to 360 days.In terms of deformation,larger amount of glass powder resulted in greater expansion and smaller self-shrinkage for glass powder added mortar cured in water;while for glass powder added mortar cured in dry-wet cycle conditions,the deformation rate firstly decreased and then increased with increasing glass powder content,and the mortar with a glass powder content of 9% possessed the lowest deformation rate.(3)The activity of glass powder and the densification of the structure of glass powder added mortar were negatively correlated with the particle size of glass powder.Therefore,the glass powder with a median particle size of 6.63 μm possessed the highest activity and the corresponding mortar possessed the best impermeability.In terms of volume deformation,under water curing conditions,the smaller the particle size of glass powder,the greater the expansion amount of mortar,the smaller the self shrinkage of mortar,the stronger the ability of mortar to resist deformation under dry and wet cycle curing,the smaller the deformation rate,and the more stable the mortar.(4)The excitation effect of the four curing conditions designed in this paper on the activity of glass powder is ranked as follows: 90 ℃ water bath curing for 3 days > water curing for 28 days > dry-wet cycle conditions curing for totally 28 days > natural curing for28 days.For glass flakes added mortar,glass flakes were arranged in a crisscross pattern inside the mortar,which significantly reduced the fluidity of mortar,In addition,the impermeability of mortar firstly increased and then decreased with the increase in glass flake content,and the mortar with a glass flake content of 6% exhibits the best impermeability.(5)The Mix Proportions of waterproof mortar was optimized through orthogonal experiments,and the prime experimental mix ratio of mortar consists of 35% cementitious material,10% glass powder,0.6% glass flake,and 0.6% sodium sulfate.The most probable pore size distribution of mortar prepared using the prime mix ratio was about 13 nm,which is much smaller than that of the blank group.Furthermore,compared with the blank group,the glass powder added mortar fabricated with the optimal mix proportion held more gel pores and less capillary pores,which reduced the penetration path of water,thus,the strength and impermeability of the mortar were improved.