What was found
ACFT DEPARTED. AFTER GEAR EXTENSION WITH 3 GREEN DOWN AND LOCKED, NO AMBER ANNUNCIATORS ILLUMINATED. IAW CONTAMINATED OPS PROCEDURES PARKING BRAKE WAS EXERCISED 3 TIMES AND STOWED. BRAKE PRESSURE ANNUNCIATOR NOT ILLUMINATED. AFTER A MATTER OF SECONDS AMBER BRAKE ANNUNCIATOR ILLUMINATED. A CHECK OF THE INDICATORS SHOW RT BRAKE RED. NORMAL TOUCHDOWN. AFTER APPROX 10 SECONDS OF ROLLOUT THE TIRES BEGAN TO FAIL ON POST FLIGHT WALKAROUND NOTICED 4 SHREDDED MAIN TIRES. FOUND ALL 4 WHEEL/BRAKE ASSYS FROZEN DUE TO ICE. REPLACED ALL 4 MLG TIRE/BRAKE ASSYS WITH O/H UNITS IAW MM 32-428 & 32-400.