Note for Airframe Structural Design - ASD By JNTU Heroes

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Section A QA1. A trial cross–section of a ribbed slab floor is shown in Fig. QA1. The floor is constructed of reinforced concrete, permanent 300 mm x 300 mm x 250 mm structural-type hollow clay blocks, of wall thickness 20 mm, and a 12 mm-plaster ceiling. The floor is continuous over several equal spans of 6.5 m, but may be treated as single span simply supported for analysis and fire resistance purposes. Check the effectiveness of the trial section; design the floor for flexure; check if deflection criteria are satisfied. Omit calculations for shear and anchorage. Take the effective depth, d = 260 mm. Characteristic loads: self weight plaster imposed = = = 3.51 kN/m2 0.25 kN/m2 4.00 kN/m2 Exposure: mild Fire resistance: 1 hour Concrete: Grade C35 Reinforcement: Grade 460 Type 2 deformed 20 mm diam. bars (Attached: BS 8110/1 Cl 3.6; BS 8110/2 Cl 4.2) QA2. The stiffened steel plate girder of Fig. QA2 is fully restrained throughout its length. Using grade S275 steel and the requirements of BS 5950, check the moment capacity of the section (ignore the web). Assuming the end panels are the most critical, check the shear capacity of the girder. No checks are required on the end posts or stiffeners. The design loading for the ultimate limit state is given in the Fig., with the point loads being transferred via UBs. QA3. Fig. QA3 gives details of the trial section for a fin wall of a warehouse building. The wall is 8 m high from d.p.c to the supported flat roof level, and the fins project on the external face. Check the flexural adequacy of the trial section under a characteristic wind pressure of 0.8 kN/m2. The wall is constructed from 15 N, 215 mm x 102.5 mm x 65 mm clay bricks, having a water absorption of 7 to 12%. The bricks are set in a grade (iii) mortar with special/normal control on manufacturing/construction. Wbrickwork = 20 kN/m3; I = 157 x 10-4 m4 (Attached information:- BS 5628:Part1, Fig. 10) Page 2 of 22

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Cork Institute of Technology - BEng in Structural Engineering - Stage 4 Semester 1 Examinations 2008-’09 - Advanced Structural Design - Section A C L C L 6500 Longitudinal section C L C L 400 40 250 300 mm x 300 mm x 250 mm structural-type hollow clay blocks 12 ceiling 100 300 Cross section at midspan Fig. QA1 Flanges = 700 x 40 740 kN A 360 B C 2400 E D 2800 740 kN 3400 F 3400 G 3400 90 kN/m I H 3400 2800 J 2400 K 360 Web = 1950 x 12.5 24000 Longitudinal Section Fig. QA2 Breadth of flange = 1971 102.5 102.5 665 stainless steel wall ties to IS 268 and Table 6 of BS 5628/1 & IS 325/1 Cross Section Fig. QA3 All dimensions in mm DO NOT SCALE 327.5 Page 3 of 22

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