Experimental Study On The Effect Of Construction Waste On Dredging Silt Reinforcement By Vacuum Preloading

Due to the rapid population growth and economic development in many coastal cities,the shortage of land resources has become an increasingly serious problem.In order to solve this problem,reclamation has become the main measures to solve the shortage of land in coastal cities and has been widely used.The soil used for reclamation by sea reclamation is mainly composed of dredger sludge,which has high water content,high compressibility and low permeability.Vacuum preloading is an effective and economical method to strengthen soft soil foundation.Because the soil particles of dredger sludge are very small,the soil particles migrate to the filter membrane surface and even enter the drainage board channel under the action of vacuum suction,which results in blockage of the drainage board and is not conducive to drainage consolidation in the subsequent vacuum preloading process.In order to improve the permeability of the dredger sludge,the construction waste with larger particles can be added into the dredger sludge.Therefore,the vacuum preloading reinforcement with construction waste mixed in the dredger sludge has been studied.Firstly,the basic properties of construction waste and dredger sludge are analyzed.Secondly,the effect of construction waste on the consolidation of dredger sludge by vacuum preloading is discussed through the laboratory model test.By vacuum preloading test of different kinds,blue bricks,red brick,concrete,concrete mixed with blue bricks,concrete mixed with red brick,blue bricks and red brick,concrete blue bricks and red brick mix)of the construction waste and a set of contains no construction waste reclamation silt are studied,the test results show that the reclamation of mud mixed with the blue brick flies in the vacuum preloading reinforcement effect is best.On this basis,the influence of the blue brick with particle size of 1-2.5mm,0.5-1mm,0.25-0.5mm and 0.075-0.25 mm on the vacuum preloading effect was further studied.The test results showed that the blue brick with particle size of 0.25-0.5mm had the best reinforcement effect.Finally,the influence of adding 0%,1.5%,3% and 4.5% green bricks into dredger fill sludge on its reinforcement effect is studied on the basis of the previous paper.The test results showed that the strength of the dredger sludge increased with the increase of the content of the dredger sludge.