檩条是常用的结构构件,上面承托屋面材料,下面支承于屋架、屋面梁或山墙。檩条是承上启下的重要构件。农村过去常用木檩条,鉴于木材资源的限制,今后将大力推广采用钢筋混凝土檩条。钢筋混凝土檩条如何设计呢?一般檩条有两种放置方法:一是正放,即檩条截面的垂直中心线与地面相垂直;二是斜放,即檩条截面的垂直中心线与屋面斜面相垂直。正放檩条的设计同一般小梁,是单向受弯构件,可按第五讲梁的设计进行计算。斜放檩条比 The purlin is a commonly used structural member that supports the roofing material and supports the roof trusses, roof beams or gables below. The purlin is an important component of the connection. In the past, rural wood rafts were commonly used. In view of the constraints of timber resources, the use of reinforced concrete purlins will be promoted in the future. How do you design a reinforced concrete stringer? There are two methods for placing a concrete stringer: The first is that the vertical centerline of the cross section of the string is perpendicular to the ground, and the second is inclined, that is, the vertical centerline of the string section is perpendicular to the slope of the roof. The design of the normal purlin is the same as the trabecular one, and it is a unidirectional bending member. The calculation can be calculated according to the design of the fifth lecture. Diagonal beam ratio