The　behaviour　of　an　asphalt　concrete　structure　subjected　to　severe　loading,　such　as　blast　and　impact　loadings,　is　becoming　critical　for　safety　and　anti-terrorist　reasons.　With　the　development　of　high-speed　computational　capabilities,　it　is　possible　to　carry　out　the　numerical　simulation　of　an　asphalt　concrete　structure　subjected　to　blast　or　impact　loading.　In　the　simulation,　the　constitutive　model　plays　a　key　role　as　the　model　defines　the　essential　physical　mechanisms　of　the　material　under　different　stress　and　loading　conditions.　In　this　paper,　the　key　features　of　the　Karagozian　and　Case　concrete　model　(KCC)　adopted　in　LSDYNA　are　evaluated　and　discussed.　The　formulations　of　the　strength　surfaces　and　the　damage　factor　in　the　KCC　model　are　verified.　Both　static　and　dynamic　tests　are　used　to　determine　the　parameters　of　asphalt　concrete　in　the　KCC　model.　The　modified　damage　factor　is　proposed　to　represent　the　higher　failure　strain　that　can　improve　the　simulation　of　the　behaviour　of　AC　material.　Furthermore,　a　series　test　of　the　asphalt　concrete　structure　subjected　to　blast　and　impact　loadings　is　conducted　and　simulated　by　using　the　KCC　model.　The　simulation　results　are　then　compared　with　those　from　both　field　and　laboratory　tests.　The　results　show　that　the　use　of　the　KCC　model　to　simulate　asphalt　concrete　structures　can　reproduce　similar　results　as　the　field　and　laboratory　test.