3. ANALYTICAL INVESTIGATION3.1 Truss configuration• Truss type: How to farm• Span length: 6.1 m• Base wind speeds: 44 m/sec• Center to center distance: 2 m• Building height: 5 mDetails of truss dimensions are given in Table 1. Roof trusses are subject to the following types of loads: • Dead loads of roof trusses include the weight of the roof covering, the weight of the purlins, the weight of the purlins and the own weight of the trusses. • Live load or imposed load IS 875-1987 (Part 2) recommends this for roofs with a slope up to 100 inclusive. The live load measured on the plan should be taken as 1,500 N/m2 when access to the roof is provided and 750 N/m2 when access is not provided, except for the roof. interview. For sloping roofs with a slope greater than 100, the surcharge may be taken at 750 N/m2 for each degree of increase in slope above 100, subject to a minimum of 400 N/m2. The live load can be taken as 2/3 of the above load• Wind LoadWind load is one of the most important loads to be considered in the design of roof trusses. A detailed wind design as per IS 875-1987 (Part 3)The three design load cases considered for analysis of roof trusses and they are:a. 1.5x (dead load + live load)b. 1.5x (dead load + wind load)c. 1.2x (Dead Load + Live Load + Wind Load) Load details are given in Table 2. TABLE 1: LATTICE DIMENSION DETAILS. 1.0226.1 0.610 1:10 110190 1.041.023 6.1 0.680 1:9 120340 1.04 1.024 6.1 0.760 1:8 140 1.05 1.025 6.1 0.870 1:7 150550 1 .026 6.1 1.020 1 :6 180260 1.07 1.027 6.1 1.220 1:5 210480 1.09 1.028 6.1 1.524 1:4 260300 1.14 1.029 6.1 2.032 ...... middle of paper ..... . it turns out to be 18o26". The weight of the different trusses is shown in table 4.TABLE 4: OPTIMUM DESIGN OF THE TRUSSRiseM Top chordMm Bottom chord mm FramesMm Weight of the trussKg0.554 100x50x20x4 80x50x25x4 50x40x15x2 980.610 8 0x40x25x4 80x50x25x4 50x40x15x2 920.680 80x40x20x3 .15 80x50x25x4 50x40x15x2 850.760 70x30x20x3.15 80x50x20x3.15 50x40x15x2 780.870 70x30x20x3.15 80x40x20x3.15 50x40x15x2 65 1.020 70x40x15x2 60x30x10x3.15 50x40x10x1.25 48. 51.220 70x40x15x3.15 60x30x20x3.15 50x40x10x1.25 52.51.524 70x30x15x2 60x30 x20x3.15 50x40x10x2 56.782. The optimal weight of the cold formed steel truss is the minimum weight of 48.5 kg corresponding to the central elevation. of 1.02 m as indicated on Figure 2. Figure 2: Optimal truss design