Guangzhou Steel news: For 8 degree area light steel roof level support
For this issue of the relevant provisions:
1, on a point of order, said portal frame is round with a belt tensioning device support, not stressed seismic intensity difference;
2, support the selection table on the portal frame's portfolio, for 8 zone has a separate selection table, but when the load is larger selection of single angle, the choice of angle for the slenderness ratio control, is seen by single lever planning, load is small selection of round;
3, seismic standards, only for steel truss roof level of support provision: steel is appropriate, by a single lever planning.
4, the steel Planning Manual, author of 8 degrees that area should be used steel portal frame level support, there is no reason to elaborate.
Guangzhou Steel diagram with round, professional leaders and workers have always advocated the use of angle on the grounds that "with angle better!"
Collapse, H-beam steel structure that Guangzhou Bai got better!
Guangzhou Steel's view: no crane with a round; there are overhead cranes, with round; there is suspension crane with angle, and press the lever planning.
Guangzhou Steel reasons:
1, light steel structure in the horizontal direction seismic performance is better, under the earthquake, allowing a greater displacement and then reset, so the roof supports are by rod planning.
2, when the seismic force in one direction and two support rods cross, an earthquake in the other direction a compression force of tension by lever if quit working for the round, to flexible deformation, etc., and then changed the rod into the work; if the angle steel and other steel bar, steel rod according to plan can not resist the pressure, will form a permanent deformation or even damage, and so on in the other direction when the seismic force, undamaged beam will be straightened, bear Rally in the reciprocating seismic force, it is easy to damage the battery, even if ultimately not damaged after the earthquake, but also need to be replaced.
3, from the force is concerned, since it is by rod planning, you can withstand the appropriate tension can, why we must steel?
4, the door frame structure and steel roof structure not look the same, namely the anti-gauge steel truss roof support in respect of the provisions do not apply to the portal frame, because steel roof truss structure, roof truss height is generally greater, their PLANE stability is not good, and the connection node too much, too big earthquake deformation, easy truss rods and nodes resulting damage, thus setting the upper and lower steel roof is supported by two strings.
5, when a single girder overhead crane or crane, the crane's horizontal forces on the column, which supports the use of a rigid support studs to roof support can still use the flexible support, the support bar. When the crane under suspension beams, cranes horizontal force on the beam, this time between the roof support and pillar support should be set rigid support. Guangzhou Steel