大口径输水管道回填新型流填料的性能研究OA

Compared with traditional pipeline backfill materials,flow fill materials have the advantages of self leveling and high soil reaction modulus,which can solve engineering problems caused by insufficient backfilling at the corners and sides of pipelines.However,ordinary slag flow filling materials still suffer from problems such as bleeding and shrinkage cracks due to their high fluidity and single composition during use.The study compared the effects of different sand and bentonite dosages on the water to solid ratio,bulk density,bleeding rate,setting time,compressive strength,and other properties of convective fillers.The results showed that,while maintaining the same fluidity(230±10mm),the addition of sand improved the particle size distribution of the flow filler and reduced its water to solid ratio.The addition of bentonite can solve the problem of bleeding caused by the high fluidity of flow fillers;Flow fillers with 5%and 10%bentonite content can be used for subsequent soil covering construction after 1 day of solidification.Taking into account the manufacturing cost and performance of flow filling materials,the optimal ratio is determined to be 5%bentonite content.Its flowability and strength meet the requirements of pipeline buried backfill materials and cushion materials.