1. Design bench width and platform depth of outdoor steel structure stairs
The width of the ladder section is generally determined by the traffic flow, and the principle is to ensure smooth traffic.
2. Design step length of steel structure stairs
The size of the steps should generally be commensurate with the size and stride of the person's feet. The size of the step includes height and width. Step height (mm): 175－215 140－160 130－150 step width (mm): 200 - 300 280－300 300－350; For adults, the minimum width of stair treads should be 220 mm and the comfortable width should be about 250 mm. The step height shall not be greater than 200mm, and the more comfortable height is about 170mm.
3. Dimensions of railings
Railings and handrails shall be of appropriate height, shape and size. The height of the handrail is the vertical distance from the center of the tread surface to the handrail surface. The height of stair handrail is generally 900mm, the height of horizontal handrail of the top stair platform is 1100 ~ 1200mm, and the height of children's handrail is 500 ~ 600mm.
4. Slope of steel stairs
When determining the gradient of stairs, factors such as walking comfort, climbing efficiency and space state should be considered. The gradient of indoor stairs is generally 20 ~ 45, and the best gradient is about 30. Generally speaking, where there are many people, high safety standards or large areas, the slope of stairs should be gentle. For auxiliary stairs used only by a few people or infrequently, the slope may be steeper, but it is better not to exceed 38.
