gray snow-covered staircase observation deck construction with high resistance to deformation even under heavy load galvanized ste

angle architecture board boards bridge construction cost covered deck deformation design detail even fabric fence floor footbridge frosted galvanized grate gray grid heavy high icing industrial information infrastructure landscape load lookout low map mesh metal mountain observation observatory orientation perforated pillar railing railings relief resistance snow snowcovered square staircase ste steel strong table tourism tourist tower transparent view welded weled winter zinc