淨(jing)空(kong)3米拱(gong)型(xing)骨架示意(yi)圖(tu)
2.5米(mi)拱型(xing)骨(gu)架示意圖(tu)
淨(jing)空2.6米(mi)拱(gong)形骨架(jia)示(shi)意(yi)圖(tu)
施(shi)工現(xian)場(chang)