Apparatus for preventing entrance of tunnel

An apparatus for cutting off approach to a tunnel for public works such as a road is provided to let drivers of succeeding vehicles know fire occurrence and to prohibit the approach of the vehicles to a tunnel when a tunnel is on fire, to give a warning to drivers of succeeding vehicles by maximizing the transfer of circumstances inside a tunnel visually and to minimize the danger of traffic accidents of succeeding vehicles by transferring circumstances inside a tunnel and minimizing dangerous factors added to the succeeding vehicles. An apparatus for cutting off approach to a tunnel for public works such as a road comprises a support(10) installed on an approach(P) of a tunnel(T) and composed of a vertical member installed to two sides of the approach of the tunnel and a horizontal member connected to the vertical member and provided with plural nozzles closely to face the approach, a water tank installed to the ground at one side of the approach to store up water for making water screen(WS), a machine room(30) provided with a circulation pump and connected with the support and the water tank to guide the water stored in the water tank to the horizontal member of the support according to orders of a control unit to be discharged to the approach via the nozzles, and a control unit built in the machine room and connected with a fire detector installed to the tunnel and the circulation pump electrically to receive fire detecting signals from the fire detector when the tunnel is on fire and to operate the circulation pump.