Kerfing　on　the　tunnel　working　face　is　one　of　effective　ways　to　promote　the　performance　of　tunnel　boring　machines　(TBMs)　in　hard　rock　masses,　since　the　rock　mass　integrity　is　reduced.　When　TBM　cutter　cuts　along　the　midline　of　two　kerfs,　the　lateral　cracks　generated　from　the　cutter　tip　could　propagate　to　the　bottom　of　adjacent　kerfs,　thus　improving　the　cutting　efficiency.　However,　the　cutter　vibration　under　such　circumstance　was　rarely　investigated.　To　analyze　the　impacts　of　kerf　depth　and　cutter　penetration　on　the　cutter　vibration,　a　series　of　full-scale　linear　cutting　tests　were　conducted　on　two　granite　samples　with　high　strength.　Kerfs　of　different　depths　were　processed　by　the　saw　before　each　cutting　on　one　sample,　while　conventional　cuttings　without　kerfs　were　performed　on　the　other　one　to　make　a　comparison.　A　vibration　monitoring　system　was　installed　in　the　cutter　holder,　three　axial　accelerations　and　forces　of　the　cutter　were　recorded　during　the　tests.　Rock　mucks　were　collected　and　sieved　to　obtain　the　muck　mass　and　coarseness　index.　It　was　found　the　intense　cutter　vibration　induced　by　the　intact　rock　cutting　could　be　alleviated　by　kerfs.　The　most　severe　vibration　was　found　in　the　cutter　normal　direction　thus　needed　to　be　focused　on.　A　greater　cutter　penetration　depth　made　the　vibration　more　intense.　The　kerf　depth　had　quadratic　correlations　with　various　vibration　parameters,　indicating　there　was　a　critical　depth　beyond　the　which　the　vibration　could　be　greatly　alleviated,　while　the　higher　rock　breaking　efficiency　could　be　also　guaranteed.　The　critical　depth　obtained　was　about　6–9　mm　within　the　range　of　experimental　design.　Variational　mode　decomposition　(VMD)　was　introduced　to　extract　two　main　subbands　and　their　central　frequencies　in　the　frequency　domain.　The　central　frequency　of　the　lower　frequency　band　had　a　bell-shaped　correlation　with　the　kerf　depth,　the　critical　depth　was　still　found　at　6　mm.　The　findings　are　conducive　to　the　design　of　the　kerf-assisted　TBM　tunnelling　and　the　prolongation　of　cutter　life.　©　2024