Modification factor βs = 310/σs σs = (310fykAs,req)/(500As,prov) = (310 × 460 × 133.688)/(500 × 452) = 84.341 N/mm2 βs = 310/84.342 = 3.67 > 2.0 (take 2.0)Taking the distance between supports as the effective span, L = 3625mmThe allowable span/depth ratio = βs × 30.838 = 2.0 × 190.327 = 280.645Actual deflection L/d = 3625/119 = 30.462Since 280.645< 30.462 Therefore, deflection is ok. Shear VerificationMaximum shear force coefficient for slab(β) = 0.44VEd = βnlxUltimate shear force VEd = 0.44 × 10.9575 × 3.625 = 17.477 kN/mVRd,c = [CRd,c.k. Slab reinforcement is a mesh and may be formed from two sets of bars placed at right angles. the maximum spacing between two secondary parallel bars in case of RCC Slab shall be 5d or 450 mm or whichever is less. Floor Slab – 1 (Two-Way Slab):-Bars along X Axis:-Bars along Y Axis:- 4. The quality of a completed floor slab is dependent on; an appropriate design, the quality of the materials used and the knowledge and experience of the workmen who place and finish the concrete. The result is a lightly reinforced slab designed to offset the effects of temperature and shrinkage of the concrete. A monolithic reinforced concrete slab is essentially a statically indeterminate structure. For instance, if the area of reinforcement required (As,req) from calculation is 523 mm2/m, you can provide H12@200 c/c (Area of steel provided As,prov = 565 mm2/m). In a typical reinforced concrete building, reinforcement bars arranged as mats are incorporated into a concrete plate of minimum thickness 125 mm to form a reinforced concrete solid slab. (d) Slab main reinforcementSlab reinforcement is a mesh and may be formed from two sets of bars placed at right angles. Table 1: Area of reinforcement per metre width of spacing. (g) Shear capacity of slabsUnder normal loads, shear stresses are not critical and shear reinforcement is not required in floor slabs. To check the shear capacity of slabs, the shear stress (vEd = VEd/bd) must be checked against the shear capacity of an unreinforced section (VRc,d). Two-way spanning slabs; Cantilever slabs; In general, there are similar requirements for one-way, and two ways slab when slab reinforcement detail drawings are prepared. For two way slabs, the precise amount and distribution of the load taken by each support, and consequently the magnitude of the bending moments on the slab, are not easily calculated if assumptions resembling real conditions are made. (100ρ1 fck)1/3, k = 1 + √(200/d) = 1 + √(200/119) = 2.296 > 2.0, therefore, k = 2, ρ1 = As/bd = 452/(1000 × 119) = 0.003798 < 0.02; K1 = 0.15. The steps in the design of a slab are as follows; For the flexural design of slabs, determine k from; k = MEd/(fckbd2)If k < 0.167, no compression reinforcement is required, and you can calculate the lever arm;z = d[0.5 + √(0.25 – 0.882k)]The area of reinforcement required is given by;As1 = MEd/(0.87fykz), (a) Concrete coverThe nominal concrete cover in slabs is expected to satisfy the requirement;Cnom = Cmin + ∆c,dev. The main Navigation tabs at top of each page are Metric - inputs in millimeters (mm). Reinforcement in slabs consists of a large number bars both ways which need to be tied together to form a mat. He is a member of the Nigerian Society of Engineers. For deemed to satisfy basic span/effective depth (limiting to depth/250);Actual L/d of the slab must be ≤ Limiting L/d × βsThe limiting basic span/ effective depth ratio is given by;L/d = K [11 + 1.5√(fck)ρ0/ρ + 3.2√(fck) (ρ0/ρ – 1)1.5] if ρ ≤ ρ0L/d = K [11 + 1.5√(fck) ρ0/(ρ – ρ’) + 1/12 √(fck) (ρ0/ρ)0.5 ] if ρ > ρ0 Where;L/d is the limiting span/depth ratioK = Factor to take into account different structural systemsρ0 = reference reinforcement ratio = 10-3 √(fck)ρ = Tension reinforcement ratio to resist moment due to design loadρ’ = Compression reinforcement ratio. The minimum area of main reinforcement has to satisfy clause 9.2.1.1(1) of Eurocode 2; As,min = (0.26fctm/fyk)btd but not less than 0.0013bdwhere bt = width (for slab design 1000 mm), d = effective depth. Rebar is often installed in a grid pattern, and to estimate the amount needed it will be important to first identify the size and spacing is appropriate for your project. 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