28m预应力折线形屋架下弦杆被压坏的事故鉴定

ACCIDENT ASSESSMENT OF COMPRESSIVE BREAK IN BOTTOM CHORD BAR OF 28m PRESTRESSED CONCRETE ROOF TRUSS

在大跨度预应力混凝土屋架施工中 ,忽视了迭层浇筑的施工技术措施 ,致使施加预应力时 ,屋架下弦杆中的压应力发生不利的变化 ,最终导致下弦杆的破坏。

In the construction of the prestressed concrete roof truss of big span, the construction technology measures are ignored in the lamella pouring, which results in an unfavorable change in the compressive stress of the bottom chord bar for the roof truss during prestressing, which finally leads to the failure of the bottom chord bar.