And road with width of 8−10 m is highly recommended in the forest area, where the stands with higher tree height all year round suffering high wind speed and slope greater than 45°. yunnanensis district in Yunnan Province of southwestern China, which can achieve better fire-prevention benefits.

Conclusion It is suggested to build the road with 6 m width in P. And the burning rate of combustibles can reach above 40 kg/s in the 60 s. And it only took about 1 min to spread 10 m on the hill. And corresponding heat release rate power can reach 3.0 × 10 5 − 9.0 × 10 5 kW. Generally, the central temperature of moderate-intensity forest fire was about 700−1 200 ℃. When wind speed reached more than 4.5 m/s, the fireproof blockade functions of forest-road width of 6 m may be lost. Comparing with the one that can better isolate medium-intensity forest-fire spreading condition can meet the one with less than 4.5 m/s wind speed and less than 45° slope.

And 6 m width road got a strong fire isolation function. And the one with more than 35° slope and greater than 4.5 m/s wind speed was easy to lose its function. And the one with 4.5 m achieved relatively poor fire-isolating function performance. Result The forest road width of 2 m failed to meet the need for fire protection and isolation.

And with the application of belt fire source with 12 m in length and 6 m in width, and heat release rate of 4.6 × 10 4 kW/m 2, which simulated moderate-intensity forest-fire, we aimed to study fire-isolating functions at different forest-road widths. Method The micro-mountains model of Pinus yunnanensis was constructed using fire dynamic simulation software PyroSim with parameters including slopes of 25°, 35° and 45°, wind speed of 1, 2.5 and 4.5 m/s, and forest-road widths of 2, 4.5 and 6 m. While giving maximum economic benefits, its function on forest fire patrol monitoring, emergency rescue, rapid transport of firefighters and equipment when happening fires also should be taken into account, as well as the function of block forest fire spreading and forest fire isolation. Objective Forest road network and its width is the basic demands of forestry production, transportation, and tourism.

Pyrosim 2019