Research On Engineering Application Of Roller Compacted Concrete Base

The traditional road semi-rigid water-stabilized base is prone to early damage,poor durability and difficult maintenance in the early stage of use,RCC has the advantages of higher strength,saving cement and short construction period,which can improve the quality of pavement engineering,but the practical application of RCC in domestic road engineering is less,There is also a lack of relevant standards and construction specifications,for this reason,relying on the struggle Reservoir entry road project,the development of road RCC Base engineering application Research,the main work and results are as follows.Carrying out the performance testing,analysis and treatment of cement,fly ash,coarse aggregate,admixture and water,it is found that the mud content and fineness modulus of natural sand fine aggregate are exceeded,and the amount of powder less than 0.16 mm is less than that of two diameter coarse aggregate,and the compatibility of water reducer with cement and fly ash is not good.Wash the natural sand fine aggregate and sift down some coarse particles to deal with it,so that the mud content and fineness modulus meet the requirements;The batching test is obtained when two diameter levels are mixed at 40:60 proportion,and the compatibility of the water reducer with cement and fly ash can be improved by using the aeration agent together with the water reducer.In this paper,the maximum dosage of RCC fly ash in this project is78.8%,the reasonable sand rate is 37%,and the suitable water glue ratio is 0.46,including the experimental study of the related problems of RCC mix ratio,fly ash blending rate,fly ash water demand ratio,roller compacted concrete working and mix ratio index,etc.RCC is suitable for water consumption of kg/m3,suitable for water reducer,gas intake agent dosage of 0.8%,0.08%,fly ash suitable total dosage of 55%,of which the suitable sand rate of fly ash is 10%,fine aggregate fineness modulus and powder content is better,high grade,good quality fly ash demand is relatively small,It is unfavorable to the performance of RCC and has little effect on the cost of roller compacted concrete.Through the field stirring and rolling test of RCC,it is determined that the optimum mixing time is 75 s,the speed of the milling machine(BW203AD-4 type)is 1.3km/h,the first runs smoothly for 2 times,then the rolling drive is crushed 8 times,and finally then the smooth running runs 2 times,which is the best rolling scheme for compaction effect and economic effect.Through laboratory and field RCC VC value time loss test,it is shown that the configured RCC can meet the needs of field construction.