Research On Properties Of Sleeve Grouting Material For Assembly Building

With the development of our country’s economy and the idea of green sustainable development,the construction technology of prefabricated buildings is getting more and more attention.The processing of joints between prefabricated components in prefabricated buildings is one of the key points to ensure the overall stability of the building,and the mechanical properties and durability of the sleeve grout used to connect the joints are the keys to ensure the performance at the joints.In order to ensure the structural stability of the building,this makes the sleeve grouting more and more demanding in terms of various properties.This paper introduces the material types of sleeve grouting.It starts with the influencing factors of the grouting and explains the research status of sleeve grouting.It designs experimental schemes and uses the method of controlling variables to qualitatively study the rubber-sand ratio,water-binder ratio,and additive Factors such as additives and mineral admixtures on the performance of sleeve grouting;and quantitative analysis of water-binder ratio,rubber-sand ratio,admixtures and mineral admixtures on sleeve grouting performance using gray correlation analysis.The degree of influence of mechanical properties and flow properties.The research results are as follows:(1)The water reducing agent has a great influence on the fluidity of the grout.A proper amount of water reducing agent can effectively improve the fluidity of the grout.Excessive amount can easily cause bleeding of the grout.There are compatibility issues when multiple additives are used in combination.The water reducer and defoamer respectively have the best blending amount when they are used.When the optimal blending amount is exceeded,the admixture no longer shows a significant positive effect and may even reduce the performance of the grout to a certain extent.The plastic expansion agent has little effect on the fluidity of the grouting material,but when the dosage reaches 0.05%,it will aggravate the fluidity loss within half an hour.(2)Within a certain range,the increase of the mortar ratio can increase the strength of the grouting material,but continuously increasing the amount of cementitious material over 1.2%,but will reduce the strength of the grouting material due to the reduction of aggregate;the mortar ratio and water The increase of the glue ratio can increase the flow performance of the grout;under the condition that other factors remain unchanged,the grout is more sensitive to water than the low water-glue ratio when the water-rubber ratio is high;The impact is greater than the mortar ratio.(3)For mineral admixtures used in grouting,when mixed alone,silica fume has the most obvious effect on the early strength improvement of sleeve grouting,and mineral powder has the most obvious effect on improving the later strength of sleeve grouting.However,increasing the amount of silica fume will cause the fluidity of the grout to decrease rapidly,while adding ore powder and fly ash can improve the fluidity of the grout,and the effect of the mineral powder on the fluidity of the grout is most obvious.When mixed with mineral admixtures,silica fume and ore powder mixed system can increase the strength of sleeve grouting material the most,while fly ash and ore powder mixed system can significantly improve the fluidity of grouting material.(4)Through correlation calculation,it was found that the two parameterswater-binder ratio and mortar-sand ratio play a leading role in the strength of the sleeve grouting at each age and the flow performance of the sleeve grouting.The early-strength water-reducing agent has a greater degree of correlation with the compressive strength and flow performance of the grout,and its influence is significantly greater than that of defoamers,expansion agents and other additives;at the same time,the degree of influence on the strength,the expansion agent is greater than defoam Agent,and the degree of influence on the flow performance of the antifoaming agent is greater than the expansion agent.The effect of silica fume on the early strength is greater than that of fly ash and mineral powder,and the effect on the later strength is less than that of fly ash and mineral powder.Fly ash and ore powder have basically the same effect on the initial flow performance of sleeve grouting material,but the effect of ore powder on the 30 min fluidity loss is higher than that of fly ash.