In　order　to　analyze　the　characteristics　of　axial　distribution　of　borehole　wall　pressure　along　the　borehole　in　rock　blasting,　the　axial　distribution　of　borehole　wall　pressure　along　the　borehole　of　coupled　charges　with　different　borehole　diameters　was　studied　by　combining　theoretical　analysis,　model　testing,　and　finite　element　simulation.　Firstly,　based　on　the　theory　of　spherical　detonation　wave,　a　model　of　the　detonation　wave　propagation　in　the　borehole　was　established.　Based　on　the　relationship　between　the　incidence　angle　of　the　detonation　wave　and　the　diameter　of　the　borehole,　the　theoretical　calculation　formula　of　the　borehole　wall　pressure　under　different　propagation　stages　of　detonation　was　derived,　and　the　change　curve　of　the　borehole　wall　pressure　along　the　axial　borehole　wall　with　different　borehole　diameters　was　obtained.　In　order　to　verify　the　rationality　of　the　theoretical　analysis,　the　concrete　thick　wall　cylinder　model　test　was　further　used　to　monitor　the　pressure　of　the　borehole　wall　by　using　a　high-speed　multichannel　dynamic　strain　test　system.　Meanwhile,　finite　element　numerical　simulation　of　different　borehole　diameters　was　established　to　obtain　the　axial　distribution　of　borehole　wall　pressure　results　of　different　borehole　diameters.　And　the　model　test　and　numerical　simulation　results　were　compared　with　the　theoretical　analysis　results.　The　results　show　that　the　coupled　charge　borehole　wall　pressure　presents　an　uneven　distribution　along　the　axial　direction　of　the　borehole,　and　the　borehole　wall　pressure　near　the　detonation　point　increases　sharply,　begins　to　decrease　exponentially　after　reaching　the　maximum　peak　pressure,　and　finally　tends　to　fluctuate　steadily.　There　is　a　positive　correlation　between　the　borehole　wall　pressure　and　the　borehole　diameter.　The　maximum　peak　pressure　and　the　stable　fluctuation　stage　of　the　borehole　wall　pressure　increase　with　the　borehole　diameter.　The　relative　error　between　the　theoretical　calculation　value　of　the　axial　borehole　wall　pressure　at　d　=40　mm　and　the　results　of　the　model　test　and　numerical　simulation　is　small,　which　verifies　the　rationality　of　the　theoretical　analysis.　©　2025　Harbin　Institute　of　Technology.　All　rights　reserved.