Emerging　automated　vehicle　(AV)　technology　is　being　deployed　on　as-built　roadways　due　to　its　promising　safety　improvements.　However,　realistic　problems　concerning　whether　and　how　perception　sensor-based　AVs　can　safely　adapt　to　the　existing　roadway　infrastructures　remain　to　be　well　addressed　due　to　a　lack　of　consideration　of　the　sensor＇s　angular　resolution　and　detection　threshold.　In　this　study,　we　aim　to　assess　whether　LiDAR-based　AVs　(LAVs)　could　safely　adapt　to　as-built　horizontal　curved　roads　from　the　perspective　of　available　sight　distances　(ASDs)　through　virtual　simulations.　In　specific,　i)　numerous　driving　scenarios　featuring　the　design　speed　(V-d:　40　similar　to　100　km/h),　circular　curve　radius　(R:　limited　minimum　radius　similar　to　common　minimum　radius),　LAV　(with　LiDAR　technical　parameters,　e.g.,　number　of　channels,　N-c:　32,　64,　128),　and　the　front　target　vehicle　were　simulated　in　PreScan/MATLAB/Simulink　co-simulation　platform;　ii)　an　ASD　extraction　algorithm　was　proposed　considering　the　point　threshold　for　detection　(N-T);　iii)　effects　of　V-d,　R,　N-c,　and　N-T　on　the　ASD　were　analyzed　and　polynomial　models　were　adopted　to　capture　relationships　between　the　ASD,　V-d,　R　at　different　N-c　and　N-T;　iv)　the　minimum　speed　against　as-built　sight　obstructions　along　the　roadside　and　the　maximum　speed　against　inadequate　sight　distance　were　proposed　by　comparing　the　ASD　with　the　required　stopping　sight　distance　of　human-driven　vehicles　and　LAVs　(level　3　similar　to　5),　respectively;　and　v)　speed　limits　(V-L)　against　inadequate　sight　distances　for　level　3　similar　to　5　LAVs　were　proposed.　The　results　indicate　that:　i)　a　larger　R　or　V-d,　fewer　N-c,　or　a　higher　N-T　would　cause　a　shorter　ASD　in　general;　ii)　attention　should　be　paid　to　the　occlusion　imposed　by　as-built　roadside　infrastructures　even　with　more　N-c　or/and　a　lower　N-T,　particularly　to　curved　roads　with　more　rigorous　geometric　design　controls　(e.g.,　small　V-d);　and　iii)　level　3　LAVs　struggle　to　adapt　to　as-built　horizontal　curved　roads,　and　level　4　or　5　LAVs　cannot　assure　adequate　ASDs　on　high-type　curved　roads　(e.g.,　large　V-d).　These　findings　shall　help　road　administrators　make　decisions　on　speed　limits　for　LAVs　on　as-built　curved　roads.