To　reduce　the　shrinkage　and　cracking　risk　of　ultra-high-performance　concrete　(UHPC),　the　autogenerous　shrinkage,　basic　mechanical　properties　(compressive　strength,　tensile　strength　and　elastic　modulus),　aggregate　gradation　and　restrained　ring　shrinkage　tests　on　five　groups　UHPCs　with　different　coarse　aggregate　contents　(mass　fractions　are　0,　12.5%,　22.5%,　32.5%,　and　42.5%,　respectively)　were　studied.　The　influences　of　coarse　aggregate　content　and　aggregate　gradation　on　the　autogenerous　shrinkage　and　basic　mechanical　properties　of　UHPC　were　analyzed.　The　proposed　relative　difference　of　shrinkage-cracking　stress　was　used　to　evaluate　the　effect　of　coarse　aggregate　incorporation　on　the　shrinkage-cracking　of　UHPC.　The　cracking　performances　of　UHPCs　with　and　without　coarse　aggregate　under　restrained　ring　were　tested　and　compared.　The　effectiveness　of　coarse　aggregate　incorporation　on　reducing　the　shrinkage-cracking　of　UHPC　was　verified,　and　the　suggestions　for　the　coarse　aggregate　content　and　the　maximum　particle　size　limitation　in　UHPC　were　given.　Research　result　shows　that　the　autogenous　shrinkage　of　UHPC　at　early　age　reduces　with　the　increase　of　coarse　aggregate　content,　and　the　maximum　decreasing　amplitude　is　about　20%.　The　effect　degrees　of　coarse　aggregate　on　the　elastic　modulus,　compressive　strength　and　tensile　strength　of　UHPC　are　depended　on　its　content　and　gradation.　When　the　coarse　aggregate　content　is　22.5%,　the　aggeregate　gradation　curve　is　almost　inside　the　range　of　Fuller＇s　and　Talbot＇s　curves.　It　is　the　most　closely　packed　group　among　the　five　material　groups.　The　coarse　aggregate　of　this　group　has　the　most　remarkable　effect　on　the　improvement　of　elastic　modulus　and　compressive　strength　of　UHPC,　and　has　the　minimum　effect　on　the　reduction　of　tensile　strength.　The　maximum　relative　difference　of　shrinkage-cracking　stress　of　UHPC　with　the　coarse　aggregate　content　of　22.5%　is　up　to　1.31　MPa.　It　is　the　optimal　content　in　the　tests　and　can　effectively　reduce　the　risk　of　shrinkage-cracking.　Comparing　the　UHPC　without　coarse　aggregate,　the　levels　of　residual　stress　and　tensile　stress　of　UHPC　with　the　coarse　aggregate　content　of　22.5%　under　the　restrained　ring　decreases　by　15.8%　and　14.7%,　respectively,　indicating　that　its　crack　resistance　improves.　The　UHPC　with　closely　packing　coarse　aggregate　is　recommended　to　achieve　the　material　properties　as　high　as　possible.　The　maximum　particle　size　of　coarse　aggregate　can　relaxes　to　9.5　mm　for　the　UHPC　with　steel　fiber　length　of　12-20　mm.　©　2019,　Editorial　Department　of　Journal　of　Traffic　and　Transportation　Engineering.　All　right　reserved.