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lattice girderis for construction use, in slab and wall. The parameters of lattice girders is as follows: 1)The upper chord made of a bar, ds= 6 to 12 mm, The bottom chord made of two bars, ds = 5 to 12mm 2) The diagonals ds= 5 to 8 mm. 3)The intervals of diagonals is 200 mm 4)The distance between the two bottom chord bars is 60 to 90mm The height of lattice girder varies from 70 to 320mm 5)The maximum length of lattice girder is 12m