Construction Technology And Application Of Cementitious Sand And Gravel Filling

The construction technology of cementitious sand and gravel is the process of creating cementitious sand and gravel with certain strength by mixing,spreading and rolling cementitious materials,such as cement and fly ash.The construction technology of cementitious sand and gravel is similar to that of roller compacted concrete,except the advantages of low requirement of aggregates,large spreading thickness and high construction efficiency.The Minjiang Navigation-Hydropower Junction mainly adopts the low dam development mode.With the total investment of 50 billion Yuan,the total installed capacity of 1.6554 million kW and the unit kW investment of 30,000 Yuan,the economic indicators are poor.To save the investment,the cementitious sand and gravel dam was proposed for the flood prevention levee in Tangba Township.The following aspects were studied,the feasibility,the economic efficiency,the adaptability on sandy pebble foundation,the selection of dam construction material,the mix proportion of materials,the design of dam structures,the construction process,quality control measures,etc.The research results show that compared with artificial aggregate,the use of sand-gravel material eliminates the processes of drilling and blasting excavation,and aggregate processing.Each cubic meter of cementitious sand and gravel aggregates can save 80 Yuan;each cubic meter of cementitious materials in CSG dam can save at least 40-50 kg,the range of investment savings is between 10.02% and24.17%,the project cost can be saved by 28%,and the construction period can be shortened by 25%.According to the current prices of quota materials,the comprehensive unit price of cementitious sand and gravel is between 200 and 300 Yuan/m2,which is cheaper than that of the rolled concrete.The research results can provide certain guidance for other dam construction projects.