The torsion steels in two sides(outside and inside) of the arc stair tread need to be reinforced possibly to resist twist moment.

对某改造工程中后增室外弧形楼梯中出现的裂缝进行分析及加固处理。

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"The main stair is strung from beams above, and the rods used to support each tread serve as guardrail for the stair," the architects explained.

建筑师解释说：“主楼梯是从上面的横梁上架起来的，用来支撑每一个踏板栏杆作为楼梯的护栏。”

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