Purlin Application In The Field Of Housing Decoration
Purlin is a building noun, a horizontal component along the length of the roof, located on the main rafters, supporting the secondary roof rafters. Purlin is roughly divided into main purlin and secondary purlin, mainly used in some housing decoration and other fields.
What are the construction requirements of purlin?
(1) Purlin in the roof truss should be arranged as far as possible at the node, to reduce the moment between bars. Purlin cross-section should be as far as possible perpendicular to the slope of the roof, diagonal steel, Purlin groove steel and Z-shaped steel purlin, it is advisable to the upper flange of the limb tip or roll edge toward the roof direction to minimize the roof load eccentricity caused by torque.
(2) Truss-type purlin of the winding bar should be perpendicular to the roof truss winding, the web should be perpendicular to the horizontal plane. At the ridge, the solid-bellied Purlin should adopt the double Purlin scheme, the truss Purlin adopts the Purlin scheme with the steel quantity, but because the Purlin's model is not easy to design and construction, Purlin it is advisable to design the double purlin.
(3) Purlin and roofing plates should be reliably connected to ensure that the roof can prevent the lateral instability and torsion of purlin. The real abdomen purlin can be used purlin support and roof truss, rigid frame connected to prevent purlin in the bearing place twist deformation and overturning, purlin and purlin should be used two of bolts connection, when the Purlin section higher should be set along the height direction.
(4) The flat truss type purlin and the lower lateral stiffness of the real-abdominal purlin, in order to maintain stability, should be set in the purlin between the bar as
Lateral support point. Purlin span 4~6m, and the roof slope slightly larger, on the load and purlin distance of the smaller purlin, can be set up a pull bar; the load or purlin distance is larger or longer than 6m purlin, can be set 2 bar, pull bar generally using diameter of $number round steel. The pressure-type steel plate roofing is reliable connection with purlin, and there are measures to ensure that purlin in the installation process of lateral stability, Purlin can not be set to pull bar.
(5) As a result of structural reasons, truss purlin generally adopt nodes have eccentric approach, because of the small internal force, generally do not calculate the node connection weld strength, Purlin and according to the structural requirements of the determination.