The　sleeve　grouting　compactness　of　a　fabricated　structure　directly　affects　its　quality　and　safety,　which　are　important.　In　this　study,　an　acoustic　emission　system　composed　of　an　acoustic　emission　instrument　and　signal　generator　is　used　to　test　the　preliminary　detection　of　sleeve　grouting　connection　compactness　via　a　reasonable　test　method.　The　acoustic　emission　characteristics　of　prefabricated　components　under　the　excitation　of　signal　generator　are　collected,　and　the　characteristics　of　acoustic　emission　signals　under　different　concrete　strength,　hollow　sleeve　positions,　and　compactness　cases　are　analyzed.　Results　show　that　the　amplitude　of　00　concrete　(66.63-66.86　dB)　is　higher　than　that　of　C40　concrete　(56.96-57.54　dB).　For　the　C40　specimen,　the　amplitude　of　the　hollow　sleeve　is　between　53.77　dB　and　54.55　dB,　which　is　lower　than　that　of　concrete.　The　amplitude　of　the　compacting　sleeve　is　between　67.61　dB　and　67.86　dB,　which　is　higher　than　that　of　the　hollow　sleeve.　The　amplitude　of　the　compacting　sleeve　after　adding　reinforcement　is　between　59.98　dB　and　60.37　dB,　which　are　lower　than　that　before　adding　reinforcement.　The　characteristic　amplitude　and　energy　of　the　acoustic　emission　signal　are　distributed　obviously　under　the　abovementioned　working　conditions.　Wavelet　analysis　for　the　received　acoustic　waveforms　was　performed　by　the　Continuous　Wavelet　Transform.　The　results　show　that　there　are　some　differences　among　the　wavelet　signals.　Hence,　the　sleeve　grouting　connection　compactness　of　fabricated　structure　can　be　detected　on　the　basis　of　acoustic　emission　technology.　(C)　2019　Elsevier　Ltd.　All　rights　reserved.