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gambrel truss joint mathmatical solution
i am in the process of designing a shed with a gambrel roof with little to no webbing utilizing wood plates to attach the joints to maximize my storage space. i have learned that when the joints are not coincident the soulution is not unique. my question is how are these types of trusses analyzed? are there other ways to get a solution with confidence if indeterminant ? below is the apporximate shape (diagram is not displayed well)

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i see these types of truss designs at a local home depot with the joints connected by steel plates with little to no triangulation and would like to use this design, however i would like to learn from it and not just wing the design.
gambrel roofs have been discussed a few times, there is almost nothing on the web about them.
also i still have the document "designing barns to withstand wind loads" on my website (link below). it will not answer your question but does have some (1930's) info on gambrel roofs.
thanks slideruleera.
i was looking through "designing barns to withstand wind loads" and noticed the complexity of the joints. it appears that when designing the joints, pre fea, each triangle is analyzed separately and then assembled as a whole with many assumptions.
in my design, using only a plate to assemble the joint mimics a triangle with some amount of bending resistance required. this type of design appears to be a truss and a beam combination without knowing what percentage of each it is acting like. the amount of bending resistance needed is what concerns me. might you have any info on moment transfer of wood joints using nails or nails and glue? i actually joined a couple of 2x6's together to form an 8' long beam with 3/4" wood plates on both sides. i made two samples varying the number of nails but keeping the spacing the same. from memory the nails were 8d common (.162" dia.) and just penetrated all the
sm69 - i do have a few leads that may be helpful:
"mechanical connections in wood structures"
thanks slideruleera. good info

2009-09-09, 02:20 PM	#1
huangyhg 超级版主注册日期: 04-03 帖子: 18592 精华: 36 现金: 249466 标准币资产: 1080358888 标准币	gambrel truss joint mathmatical solution gambrel truss joint mathmatical solution i am in the process of designing a shed with a gambrel roof with little to no webbing utilizing wood plates to attach the joints to maximize my storage space. i have learned that when the joints are not coincident the soulution is not unique. my question is how are these types of trusses analyzed? are there other ways to get a solution with confidence if indeterminant ? below is the apporximate shape (diagram is not displayed well) >< > < > < / \ / \ / \ /__________________\ i see these types of truss designs at a local home depot with the joints connected by steel plates with little to no triangulation and would like to use this design, however i would like to learn from it and not just wing the design. gambrel roofs have been discussed a few times, there is almost nothing on the web about them. also i still have the document "designing barns to withstand wind loads" on my website (link below). it will not answer your question but does have some (1930's) info on gambrel roofs. thanks slideruleera. i was looking through "designing barns to withstand wind loads" and noticed the complexity of the joints. it appears that when designing the joints, pre fea, each triangle is analyzed separately and then assembled as a whole with many assumptions. in my design, using only a plate to assemble the joint mimics a triangle with some amount of bending resistance required. this type of design appears to be a truss and a beam combination without knowing what percentage of each it is acting like. the amount of bending resistance needed is what concerns me. might you have any info on moment transfer of wood joints using nails or nails and glue? i actually joined a couple of 2x6's together to form an 8' long beam with 3/4" wood plates on both sides. i made two samples varying the number of nails but keeping the spacing the same. from memory the nails were 8d common (.162" dia.) and just penetrated all the sm69 - i do have a few leads that may be helpful: "mechanical connections in wood structures" thanks slideruleera. good info __________________ 借用达朗贝尔的名言：前进吧，你会得到信心! [url="http://www.dimcax.com"]几何尺寸与公差标准[/url]