Beam Shear - 4

[Audio] Let us now investigate the shear reinforcement design of the RC beam with the commercial software RAPT 6.6.6.0..

[Audio] Within RAPT, first, define the inputs within the Input dialog tab, then, General. Define the code of practice and material as, BS 8110. Define the reinforcement type as, Reinforced instead of Post-Tensioned. Define the Panel Type as, Internal instead of External. Define the Member Type as, Beam instead of Slab. Define the Strip Type as, One Way - Nominal Width. For beams, the One way - Nominal Width, is the only option allowed. Effectively, this option allows a flange for the beam. As an aside, had the Member Type been defined as Slab instead of Beam, 4 options of Strip Type are available. The One way - Nominal Width option, would refer to a fixed 1000mm wide one way spanning slab design strip. The One way - Full Width option, would refer to a user-defined variable width one way spanning slab design strip. The Two way option, would refer to a flat slab with column and middle design strips, with the associated apportionment of full tributary effects. The Two way - Average option, would refer to a flat slab with full tributary width design strips, primarily for post-tensioned flat slabs..

[Audio] Next, define the Concrete - Spanning Members as, C28/35 in MPa or Newton/mm2. Define the Top Reinforcement Axis Depth Limit as, 1000mm minus 917mm effective depth, d, as before, yielding 83mm. This is consistent with our previous effective depth, d, calculations that assume a 25mm cover, 10mm link, and 2 layers of T32 rebar, separated by a 32mm spacer. Thus, this software would not design the detailing arrangement, instead, the user is to assume an effective depth prior to the design, and ensure consistency on completion of the design. Finally, define Pattern Live Load as, No or crossed out. Pattern live loading has a significant effect on the bending moments and deflections if the live load magnitude is high in relation to the dead loads. Thus in general, this is a consideration that must be made, but in this example lesson, we shall exclude it for benchmarking purposes with our other methods of analysis and design..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Spans. Define the number of beam spans as 5. Define the beam span lengths as 10,000mm. Define the beam flange (i.e. slab) thickness, as 200mm. Define the beam flange (i.e. slab) width, as 5,000mm. The beam flange (i.e. slab) width contributes to the self-weight of the flanged beam section, and the loading tributary for panel loads. Note that it does not contribute to the flanged beam stiffness, as that will be governed by the effective beam flange width, which is to be subsequently defined..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Columns. Define the column stiffnesses by defining column dimensions. However, in this lesson, we shall employ pinned (or knife-edge) supports, for the purpose of benchmarking our results with the other analysis methods..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Beams. Define the beam depth, as 1,000mm. Define the beam top width, as 500mm. Define the beam bottom width, as 500mm. Define the beam effective width, as 0, to enable RAPT to perform an automatic calculation to compute the beam effective width, which in general, is approximately, the beam width bw, + the span L, divided by 7.14..

[Audio] Next, define the inputs within the Input dialog tab, then Loads, then, Cases. Check the definition of the self-weight, as a line load, performed automatically by RAPT, as 35kN/m, consistent with the previous hand calculations. The figure shows that RAPT, has indeed subtracted out the beam-slab self-weight overlap of -2.5kN/m..

[Audio] Next, insert the slab superimposed dead load, as a full tributary width panel load, of 15kPa, consistent with the previous hand calculations..

[Audio] Next, insert the slab live load, as a full tributary width panel load, of 10kPa, consistent with the previous hand calculations..

[Audio] Next, define the inputs within the Input dialog tab, then Design Data, then Crack Control tab. Define the crack width calculations control as 0.30mm in general. However in this lesson, we shall not introduce a crack control mechanism, as RAPT would otherwise automatically add reinforcement, to ensure that the crack width magnitude specified, is not exceeded. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude the crack width control requirements..

[Audio] Next, define the deflection calculations control maximum value of I effective over I gross as 1.0, instead of the default 0.60. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude any maximum limit to the effective second moment of area of the beam section due to cracking..

[Audio] Next, for us to benchmark against the other methods of design, we shall exclude shear enhancement at supports, and define the beam shear critical section at the face of the support itself. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] The bending moment and shear force analysis results are obtained by choosing the Output dialog tab, then, Bending Moments, then, Load Combinations, then, Ultimate Design, then, Flexure, then, Graphics to display the beam bending moment and shear force diagrams. For the load combination case 1.4G+1.6Q, the structural analysis results in a hogging bending moment for the interior span of 1,849 kilo Newton metre, and sagging bending moment for the interior span of 1,075 kilo Newton metre, both figures being similar to that which is estimated by the hand method of calculation. For the load combination case 1.4G+1.6Q, the structural analysis results in a shear force for the interior span of 1,170kN, again being similar to that which is estimated by the hand method of calculation..

[Audio] The deflection analysis results are obtained by choosing the Output dialog tab, then, Deflections, then, All Spans Loaded, then, Graphics to display the total long term beam deflection diagram. For the load combination case 1.0G+1.0Q, the structural analysis results in a deflection for the end span of 23mm, herewith somewhat greater than that which is estimated by the hand method of calculation. Note that RAPT automatically calculates the long-term creep and cracked deflections. It also increases the stiffness, according to the specified effective flange width, which is offset from the beam stem centroid, as defined in the beam geometrical input. Thus the deflection estimates in RAPT, automatically caters for all these 3 effects, and thus, a manual beam stiffness modification is not necessary..

[Audio] The reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Beam, then, Text. The design ULS shear is shown as, Vd = 1,242kN. The concrete shear capacity, Vc, is calculated as 281kN. This is on the basis of the provision of longitudinal reinforcement, totalling an area of 5,574 millimetre squared. The ultimate concrete shear capacity, V ult, is calculated as 2,170kN. The required area of shear steel reinforcement, Asv/S, is then shown as 2,230 millimetre squared per metre, or 2.230 millimetre squared per millimetre. Accordingly, the shear capacity is calculated in terms of a concrete component, Vc of 281kN, and a steel component, V s of 896kN. And so, all the input and output parameters are somewhat similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is EC2, chosen by selecting Input dialog tab, then, General, then, the Design Code and Material as EC2 (UK). The choice of the national annex, of the UK for instance, is important in the beam shear design because, the coefficient alpha cc for shear of 1.00 (stipulated within clause 3.1.6(1) of the EC2), features within the design value of concrete compressive strength, fcd equation, which in turn, features within the concrete maximum shear strength, vRd,max(45) equation..

[Audio] Define the reinforcement type as, Reinforced instead of Post-Tensioned. Define the Panel Type as, Internal instead of External. Define the Member Type as, Beam instead of Slab. Define the Strip Type as, One Way - Nominal Width. For beams, the One way - Nominal Width, is the only option allowed. Effectively, this option allows a flange for the beam. As an aside, had the Member Type been defined as Slab instead of Beam, 4 options of Strip Type are available. The One way - Nominal Width option, would refer to a fixed 1000mm wide one way spanning slab design strip. The One way - Full Width option, would refer to a user-defined variable width one way spanning slab design strip. The Two way option, would refer to a flat slab with column and middle design strips, with the associated apportionment of full tributary effects. The Two way - Average option, would refer to a flat slab with full tributary width design strips, primarily for post-tensioned flat slabs..

[Audio] Again, define the Concrete - Spanning Members as, C28/35 in MPa or Newton/mm2. Define the Top Reinforcement Axis Depth Limit as, 1000mm minus 917mm effective depth, d, as before, yielding 83mm. This is consistent with our previous effective depth, d, calculations that assume a 25mm cover, 10mm link, and 2 layers of T32 rebar, separated by a 32mm spacer. Thus, this software would not design the detailing arrangement, instead, the user is to assume an effective depth prior to the design, and ensure consistency on completion of the design. Finally, define Pattern Live Load as, No or crossed out. Pattern live loading has a significant effect on the bending moments and deflections if the live load magnitude is high in relation to the dead loads. Thus in general, this is a consideration that must be made, but in this example lesson, we shall exclude it for benchmarking purposes with our other methods of analysis and design..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Spans. Define the number of beam spans as 5. Define the beam span lengths as 10,000mm. Define the beam flange (i.e. slab) thickness, as 200mm. Define the beam flange (i.e. slab) width, as 5,000mm. The beam flange (i.e. slab) width contributes to the self-weight of the flanged beam section, and the loading tributary for panel or area loads. Note that it does not contribute to the flanged beam stiffness, as that will be governed by the effective beam flange width, which is to be subsequently defined..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Columns. Define the column stiffnesses by defining column dimensions. However, in this lesson, we shall employ pinned (or knife-edge) supports, for the purpose of benchmarking our results with the other analysis methods..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Beams. Define the beam depth, as 1,000mm. Define the beam top width, as 500mm. Define the beam bottom width, as 500mm. Define the beam effective width, as 0, to enable RAPT to perform an automatic calculation to compute the beam effective width..

[Audio] Next, define the inputs within the Input dialog tab, then Loads, then, Cases. Check the definition of the self-weight, as a line load, performed automatically by RAPT, as 35kN/m, consistent with the previous hand calculations. The figure shows that RAPT, has indeed subtracted out the beam-slab self-weight overlap of -2.5kN/m..

[Audio] Next, insert the slab superimposed dead load, as a full tributary width panel load, of 15kPa, consistent with the previous hand calculations..

[Audio] Next, insert the slab live load, as a full tributary width panel load, of 10kPa, consistent with the previous hand calculations..

[Audio] Next, define the inputs within the Input dialog tab, then Design Data, then Crack Control tab. Define the crack width calculations control as 0.30mm in general. However in this lesson, we shall not introduce a crack control mechanism, as RAPT would otherwise automatically add reinforcement, to ensure that the crack width magnitude specified, is not exceeded. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude the crack width control requirements..

[Audio] Next, define the deflection calculations control maximum value of I effective over I gross as 1.0, instead of the default 0.60. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude any maximum limit to the effective second moment of area of the beam section due to cracking..

[Audio] Next, for us to benchmark against the other methods of design, we shall exclude shear enhancement at supports, and define the beam shear critical section at the face of the support itself. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] The bending moment and shear force analysis results are obtained by choosing the Output dialog tab, then, Bending Moments, then, Load Combinations, then, Ultimate Design, then, Flexure, then, Graphics to display the beam bending moment and shear force diagrams. For the load combination case 1.4G+1.6Q, the structural analysis results in a hogging bending moment for the interior span of 1,799 kilo Newton metre, and sagging bending moment for the interior span of 1,125 kilo Newton metre, both figures being similar to that which is estimated by the hand method of calculation. For the load combination case 1.4G+1.6Q, the structural analysis results in a shear force for the interior span of 1,170kN, again being similar to that which is estimated by the hand method of calculation..

[Audio] The deflection analysis results are obtained by choosing the Output dialog tab, then, Deflections, then, All Spans Loaded, then, Graphics to display the total long term beam deflection diagram. For the load combination case 1.0G+1.0Q, the structural analysis results in a deflection for the end span of 21mm, herewith somewhat greater than that which is estimated by the hand method of calculation. Note that RAPT automatically calculates the long-term creep and cracked deflections. It also increases the stiffness, according to the specified effective flange width, which is offset from the beam stem centroid, as defined in the beam geometrical input. Thus the deflection estimates in RAPT, automatically caters for all these 3 effects, and thus, a manual beam stiffness modification is not necessary..

[Audio] The reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Beam, then, Text. The design ULS shear is shown as, Vd = 1,237kN. The concrete shear capacity, VRd,c, is calculated as 259kN. This is on the basis of the provision of longitudinal reinforcement, totalling an area of 5,427 millimetre squared. The ultimate concrete shear capacity, V ult, is calculated as 2,052kN. The required area of shear steel reinforcement, Asv/S, is then shown as 1,380 millimetre squared per metre, or 1.380 millimetre squared per millimetre. Accordingly, the shear capacity is calculated in terms of only the steel component, V s of 1,237kN. And so, all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is ACI318 14, chosen by selecting Input dialog tab, then, General, then, the Design Code as ACI318 14 and Material as EC2 (UK) in order to maintain calculations in SI units..

[Audio] Define the reinforcement type as, Reinforced instead of Post-Tensioned. Define the Panel Type as, Internal instead of External. Define the Member Type as, Beam instead of Slab. Define the Strip Type as, One Way - Nominal Width. For beams, the One way - Nominal Width, is the only option allowed. Effectively, this option allows a flange for the beam. As an aside, had the Member Type been defined as Slab instead of Beam, 4 options of Strip Type are available. The One way - Nominal Width option, would refer to a fixed 1000mm wide one way spanning slab design strip. The One way - Full Width option, would refer to a user-defined variable width one way spanning slab design strip. The Two way option, would refer to a flat slab with column and middle design strips, with the associated apportionment of full tributary effects. The Two way - Average option, would refer to a flat slab with full tributary width design strips, primarily for post-tensioned flat slabs..

[Audio] Again, define the Concrete - Spanning Members as, C28/35 in MPa or Newton/mm2. Define the Top Reinforcement Axis Depth Limit as, 1000mm minus 917mm effective depth, d, as before, yielding 83mm. This is consistent with our previous effective depth, d, calculations that assume a 25mm cover, 10mm link, and 2 layers of T32 rebar, separated by a 32mm spacer. Thus, this software would not design the detailing arrangement, instead, the user is to assume an effective depth prior to the design, and ensure consistency on completion of the design. Finally, define Pattern Live Load as, No or crossed out. Pattern live loading has a significant effect on the bending moments and deflections if the live load magnitude is high in relation to the dead loads. Thus in general, this is a consideration that must be made, but in this example lesson, we shall exclude it for benchmarking purposes with our other methods of analysis and design..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Spans. Define the number of beam spans as 5. Define the beam span lengths as 10,000mm. Define the beam flange (i.e. slab) thickness, as 200mm. Define the beam flange (i.e. slab) width, as 5,000mm. The beam flange (i.e. slab) width contributes to the self-weight of the flanged beam section, and the loading tributary for panel or area loads. Note that it does not contribute to the flanged beam stiffness, as that will be governed by the effective beam flange width, which is to be subsequently defined..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Columns. Define the column stiffnesses by defining column dimensions. However, in this lesson, we shall employ pinned (or knife-edge) supports, for the purpose of benchmarking our results with the other analysis methods..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Beams. Define the beam depth, as 1,000mm. Define the beam top width, as 500mm. Define the beam bottom width, as 500mm. Define the beam effective width, as 0, to enable RAPT to perform an automatic calculation to compute the beam effective width..

[Audio] Next, define the inputs within the Input dialog tab, then Loads, then, Cases. Check the definition of the self-weight, as a line load, performed automatically by RAPT, as 35kN/m, consistent with the previous hand calculations. The figure shows that RAPT, has indeed subtracted out the beam-slab self-weight overlap of -2.5kN/m..

[Audio] Next, insert the slab superimposed dead load, as a full tributary width panel load, of 15kPa, consistent with the previous hand calculations..

[Audio] Next, insert the slab live load, as a full tributary width panel load, of 10kPa, consistent with the previous hand calculations..

[Audio] Next, define the inputs within the Input dialog tab, then Design Data, then Crack Control tab. Define the crack width calculations control as 0.30mm in general. However in this lesson, we shall not introduce a crack control mechanism, as RAPT would otherwise automatically add reinforcement, to ensure that the crack width magnitude specified, is not exceeded. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude the crack width control requirements..

[Audio] Next, define the deflection calculations control maximum value of I effective over I gross as 1.0, instead of the default 0.60. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude any maximum limit to the effective second moment of area of the beam section due to cracking..

[Audio] Next, for us to benchmark against the other methods of design, we shall exclude shear enhancement at supports, and define the beam shear critical section at the face of the support itself. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] The bending moment and shear force analysis results are obtained by choosing the Output dialog tab, then, Bending Moments, then, Load Combinations, then, Ultimate Design, then, Flexure, then, Graphics to display the beam bending moment and shear force diagrams. For the load combination case 1.4G+1.6Q, the structural analysis results in a hogging bending moment for the interior span of 1,799 kilo Newton metre, and sagging bending moment for the interior span of 1,125 kilo Newton metre, both figures being similar to that which is estimated by the hand method of calculation. For the load combination case 1.4G+1.6Q, the structural analysis results in a shear force for the interior span of 1,170kN, again being similar to that which is estimated by the hand method of calculation..

[Audio] The deflection analysis results are obtained by choosing the Output dialog tab, then, Deflections, then, All Spans Loaded, then, Graphics to display the total long term beam deflection diagram. For the load combination case 1.0G+1.0Q, the structural analysis results in a deflection for the end span of 25mm, herewith somewhat greater than that which is estimated by the hand method of calculation. Note that RAPT automatically calculates the long-term creep and cracked deflections. It also increases the stiffness, according to the specified effective flange width, which is offset from the beam stem centroid, as defined in the beam geometrical input. Thus the deflection estimates in RAPT, automatically caters for all these 3 effects, and thus, a manual beam stiffness modification is not necessary..

[Audio] The reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Beam, then, Text. The design ULS shear is shown as, Vd* = 1,237kN. The concrete shear capacity, Vc, is calculated as 327kN. The ultimate concrete shear capacity, V ult, is calculated as 1,540kN. The required area of shear steel reinforcement, Asv/S, is then shown as 2,880 millimetre squared per metre, or 2.880 millimetre squared per millimetre. Accordingly, the shear capacity is calculated in terms of only the steel component, V s of 910kN. And so, all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is AS3600 2018, chosen by selecting Input dialog tab, then, General, then, the Design Code as AS3600 2018 and Material as AS3600 2018..

[Audio] Define the reinforcement type as, Reinforced instead of Post-Tensioned. Define the Panel Type as, Internal instead of External. Define the Member Type as, Beam instead of Slab. Define the Strip Type as, One Way - Nominal Width. For beams, the One way - Nominal Width, is the only option allowed. Effectively, this option allows a flange for the beam. As an aside, had the Member Type been defined as Slab instead of Beam, 4 options of Strip Type are available. The One way - Nominal Width option, would refer to a fixed 1000mm wide one way spanning slab design strip. The One way - Full Width option, would refer to a user-defined variable width one way spanning slab design strip. The Two way option, would refer to a flat slab with column and middle design strips, with the associated apportionment of full tributary effects. The Two way - Average option, would refer to a flat slab with full tributary width design strips, primarily for post-tensioned flat slabs..

[Audio] Again, define the Concrete - Spanning Members as, C28/35 in MPa or Newton/mm2. Define the Top Reinforcement Axis Depth Limit as, 1000mm minus 917mm effective depth, d, as before, yielding 83mm. This is consistent with our previous effective depth, d, calculations that assume a 25mm cover, 10mm link, and 2 layers of T32 rebar, separated by a 32mm spacer. Thus, this software would not design the detailing arrangement, instead, the user is to assume an effective depth prior to the design, and ensure consistency on completion of the design. Finally, define Pattern Live Load as, No or crossed out. Pattern live loading has a significant effect on the bending moments and deflections if the live load magnitude is high in relation to the dead loads. Thus in general, this is a consideration that must be made, but in this example lesson, we shall exclude it for benchmarking purposes with our other methods of analysis and design..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Spans. Define the number of beam spans as 5. Define the beam span lengths as 10,000mm. Define the beam flange (i.e. slab) thickness, as 200mm. Define the beam flange (i.e. slab) width, as 5,000mm. The beam flange (i.e. slab) width contributes to the self-weight of the flanged beam section, and the loading tributary for panel or area loads. Note that it does not contribute to the flanged beam stiffness, as that will be governed by the effective beam flange width, which is to be subsequently defined..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Columns. Define the column stiffnesses by defining column dimensions. However, in this lesson, we shall employ pinned (or knife-edge) supports, for the purpose of benchmarking our results with the other analysis methods..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Beams. Define the beam depth, as 1,000mm. Define the beam top width, as 500mm. Define the beam bottom width, as 500mm. Define the beam effective width, as 0, to enable RAPT to perform an automatic calculation to compute the beam effective width..

[Audio] Next, define the inputs within the Input dialog tab, then Loads, then, Cases. Check the definition of the self-weight, as a line load, performed automatically by RAPT, as 35kN/m, consistent with the previous hand calculations. The figure shows that RAPT, has indeed subtracted out the beam-slab self-weight overlap of -2.5kN/m..

[Audio] Next, insert the slab superimposed dead load, as a full tributary width panel load, of 15kPa, consistent with the previous hand calculations..

[Audio] Next, insert the slab live load, as a full tributary width panel load, of 10kPa, consistent with the previous hand calculations..

[Audio] Next, define the inputs within the Input dialog tab, then Design Data, then Crack Control tab. Define the crack width calculations control as 0.30mm in general. However in this lesson, we shall not introduce a crack control mechanism, as RAPT would otherwise automatically add reinforcement, to ensure that the crack width magnitude specified, is not exceeded. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude the crack width control requirements..

[Audio] Next, define the deflection calculations control maximum value of I effective over I gross as 1.0, instead of the default 0.60. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude any maximum limit to the effective second moment of area of the beam section due to cracking..

[Audio] Next, for us to benchmark against the other methods of design, we shall exclude shear enhancement at supports, and define the beam shear critical section at the face of the support itself. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] The bending moment and shear force analysis results are obtained by choosing the Output dialog tab, then, Bending Moments, then, Load Combinations, then, Ultimate Design, then, Flexure, then, Graphics to display the beam bending moment and shear force diagrams. For the load combination case 1.4G+1.6Q, the structural analysis results in a hogging bending moment for the interior span of 1,799 kilo Newton metre, and sagging bending moment for the interior span of 1,125 kilo Newton metre, both figures being similar to that which is estimated by the hand method of calculation. For the load combination case 1.4G+1.6Q, the structural analysis results in a shear force for the interior span of 1,170kN, again being similar to that which is estimated by the hand method of calculation..

[Audio] The deflection analysis results are obtained by choosing the Output dialog tab, then, Deflections, then, All Spans Loaded, then, Graphics to display the total long term beam deflection diagram. For the load combination case 1.0G+1.0Q, the structural analysis results in a deflection for the end span of 24mm, herewith somewhat greater than that which is estimated by the hand method of calculation. Note that RAPT automatically calculates the long-term creep and cracked deflections. It also increases the stiffness, according to the specified effective flange width, which is offset from the beam stem centroid, as defined in the beam geometrical input. Thus the deflection estimates in RAPT, automatically caters for all these 3 effects, and thus, a manual beam stiffness modification is not necessary..

[Audio] The reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Beam, then, Text. The design ULS shear is shown as, Vd* = 1,237kN. The concrete shear capacity, Vc, is calculated as 126kN. The ultimate concrete shear capacity, V ult, is calculated as 2,206kN. The required area of shear steel reinforcement, Asv/S, is then shown as 3,010 millimetre squared per metre, or 3.010 millimetre squared per millimetre. Accordingly, the shear capacity is calculated in terms of only the steel component, V s of 1,057kN..

[Audio] Let us now investigate the shear reinforcement design of the RC beam with the online software EurocodeApplied.com..

[Audio] The design report shows the design input and output parameters. The beam concrete grade is entered as C28/35, i.e. concrete cylinder strength of 28Newton/mm2. The steel yield strength, fyv is entered as 500Newton/mm2. The provided area of longitudinal reinforcement of 8 numbers of T32 is inserted, totalling an area of 6,434 millimetre squared, or 64.34 centimetre squared. The effective depth is manually entered as, d = 917mm, or 0.917m, for consistency with the other calculation methods. The beam width is entered as, b = 500mm. The design ULS shear is entered as, Vd = 1,170kN. Next, the Nationally Defined Parameters (NDP), in particular the coefficient alpha cc for shear is inserted as 1.00, as stipulated within clause 3.1.6(1) of the EC2. This coefficient features within the design value of concrete compressive strength, fcd equation, which in turn, features within the concrete maximum shear strength, vRd,max(45) equation. The concrete partial material safety factor, gamma c, is then entered as 1.5. The steel reinforcement partial material safety factor, gamma s, is then entered as 1.15. The required area of shear steel reinforcement, Asv/S, is calculated as 1.304 millimetre squared per millimetre. The concrete shear strength, vRd,c, is calculated as 0.60Newton/mm2. This is on the basis of the provision of 8 numbers of T32 longitudinal reinforcement, totalling an area of 6,434 millimetre squared. And so, all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] Let us now investigate the shear reinforcement design of the RC beam with the online software Calcpad.eu..

[Audio] The design report shows the design input and output parameters. The beam concrete grade is entered as C28/35, i.e. concrete cylinder strength of 28Newton/mm2. The steel yield strength, fyv is entered as 500Newton/mm2. The provided area of longitudinal reinforcement of 8 numbers of T32 is inserted, totalling an area of 6,434 millimetre squared, or 64.34 centimetre squared. The effective depth is manually entered as, d = 917mm, or 0.917m, for consistency with the other calculation methods. The beam width is entered as, b = 500mm, and depth as, h = 1,000mm. The design ULS shear is entered as, Vd = 1,170kN. Next, the Nationally Defined Parameters (NDP), in particular the coefficient alpha cc for shear is inserted as 1.00, as stipulated within clause 3.1.6(1) of the EC2. This coefficient features within the design value of concrete compressive strength, fcd equation, which in turn, features within the concrete maximum shear strength, vRd,max(45) equation. The concrete partial material safety factor, gamma c, is then entered as 1.5. The steel reinforcement partial material safety factor, gamma s, is then entered as 1.15. The concrete shear strength, vRd,c, is calculated as 0.60Newton/mm2. This is on the basis of the provision of 8 numbers of T32 longitudinal reinforcement, totalling an area of 6,434 millimetre squared..

[Audio] The ultimate shear strength limit vRd,max(45) is calculated as 4.48Newton/mm2. The required area of shear steel reinforcement, Asv/S, is calculated as 1.304 millimetre squared per millimetre. And so, all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] Tabulated herewith is the comparison of effects and results from all the software, for all the presented codes of practice, showing good similarity between software, and the expected consistent variation across codes of practice. Note that for a like-for-like comparison, the effects had been generated for all codes based on the same load factors within the critical ULS loading combination case, and not code-specific load factors stipulated by the respective codes themselves..

[Audio] Let us now investigate the shear reinforcement design of the RC flat slab with the commercial software CSC Orion R18 SP5..

[Audio] We had established that the ULS loading pressure on our hypothetical flat slab is 23.4kPa. This ULS loading pressure acts over an area of 10m by 10m, i.e. 100m2, on each internal column, resulting in a column axial force of 2,340kN..

[Audio] Right-clicking a column and selecting Column Punching Check, then, Design, to perform the punching shear check..

[Audio] The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vc, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are somewhat similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is EC2, chosen by selecting the command Run, then, Building Analysis, then, Pre-Analysis Tab, then, Parameters..

[Audio] Correspondingly, the concrete slab material grade is chosen as C28/35, i.e. concrete characteristic cylinder strength of 28Newton/mm2, and reinforcement yield strength of 500Newton/mm2, with a factor of safety of 1.15. When the code of practice EC2 is selected, the concrete material strengths are automatically expected to be entered as, concrete cylinder strengths. The structural analysis could then be reperformed by selecting Run, then Building Analysis, then, Analysis Tab, then, Start Building Analysis..

[Audio] Right-clicking a column and selecting Column Punching Check, then, Design, to perform the punching shear check..

[Audio] The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vRd,c, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are somewhat similar to that which is obtained by the hand method of calculation..

[Audio] Let us now investigate the shear reinforcement design of the RC flat slab with the commercial software ProtaStructure 2019 SP7..

[Audio] We had established that the ULS loading pressure on our hypothetical flat slab is 23.4kPa. This ULS loading pressure acts over an area of 10m by 10m, i.e. 100m2, on each internal column, resulting in a column axial force of 2,340kN..

[Audio] Right-clicking a column and selecting Column Punching Check, then, Design, to perform the punching shear check..

[Audio] The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vc, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is EC2, chosen by selecting the command Analysis, then, Building Analysis, then, Project Parameters and Loading Tab, then, Parameters..

[Audio] Correspondingly, the concrete slab material grade is chosen as C28/35, i.e. concrete characteristic cylinder strength of 28Newton/mm2, and reinforcement yield strength of 500Newton/mm2, with a factor of safety of 1.15. When the code of practice EC2 is selected, the concrete material strengths are automatically expected to be entered as, concrete cylinder strengths. The structural analysis could then be reperformed by selecting Analysis, then Building Analysis, then, Analysis Tab, then, Start Building Analysis..

[Audio] Right-clicking a column and selecting Column Punching Check, then, Design, to perform the punching shear check..

[Audio] The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vRd,c, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are somewhat similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is ACI318 14, chosen by selecting the command Analysis, then, Building Analysis, then, Project Parameters and Loading Tab, then, Parameters..

[Audio] Correspondingly, the concrete slab material grade is chosen as C28/35, i.e. concrete characteristic cylinder strength of 28Newton/mm2, and reinforcement yield strength of 460Newton/mm2, with a factor of safety of 1.15. When the code of practice ACI318 is selected, the concrete material strengths are automatically expected to be entered as, concrete cylinder strengths. The structural analysis could then be reperformed by selecting Analysis, then Building Analysis, then, Analysis Tab, then, Start Building Analysis..

[Audio] Right-clicking a column and selecting Column Punching Check, then, Design, to perform the punching shear check..

[Audio] The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, phi times vc, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. However, not all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] Let us now investigate the shear reinforcement design of the RC flat slab with the commercial software RAPT 6.6.6.0..

[Audio] Within RAPT, first, define the inputs within the Input dialog tab, then, General. Define the code of practice and material as, BS 8110. Define the reinforcement type as, Reinforced instead of Post-Tensioned. Define the Panel Type as, Internal instead of External. Define the Member Type as, Slab instead of Beam. Define the Strip Type as, Two way. For beams, the One way - Nominal Width, is the only option allowed. Effectively, this option allows a rectangular beam section with a flange. For slabs, 4 options of Strip Type are available. The One way - Nominal Width option, would refer to a fixed 1000mm wide one way spanning slab design strip. The One way - Full Width option, would refer to a user-defined variable width one way spanning slab design strip. The Two way option, would refer to a flat slab with column and middle design strips, with the associated apportionment of full tributary effects. The Two way - Average option, would refer to a flat slab with full tributary width design strips, primarily for post-tensioned flat slabs..

[Audio] Next, define the Concrete - Spanning Members as, C28/35 in MPa or Newton/mm2. Define the Top Reinforcement Axis Depth Limit as, 400mm minus 345mm effective depth, d, yielding 55mm. This is consistent with our previous effective depth, d, figure. Thus, this software would not design the detailing arrangement, instead, the user is to assume an effective depth prior to the design, and ensure consistency on completion of the design. Finally, define Pattern Live Load as, No or crossed out. Pattern live loading has a significant effect on the bending moments and deflections if the live load magnitude is high in relation to the dead loads. Thus in general, this is a consideration that must be made, but in this example lesson, we shall exclude it for benchmarking purposes with our other methods of analysis and design..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Spans. Define the number of slab spans as 5. Define the slab span lengths as 10,000mm. Define the slab thickness, as 400mm. Define the slab width (i.e. section tributary), as 10,000mm. This refers to the full tributary width flat slab section. The slab width contributes to the self-weight of the slab panel, the loading tributary for panel loads, and the slab section stiffness..

[Audio] Next, define the inputs within the Input dialog tab, then Frame, then, Columns. Define the column stiffnesses by defining column dimensions of 800mm times 800mm, with a floor to floor height of 3,000mm..

[Audio] Next, define the inputs within the Input dialog tab, then Loads, then, Cases. Check the definition of the self-weight, as a panel load, performed automatically by RAPT, as 10.0kPa, consistent with the previous hand calculations..

[Audio] Next, insert the slab superimposed dead load, as a full tributary width panel load, of 1.0kPa, consistent with the previous hand calculations..

[Audio] Next, insert the slab live load, as a full tributary width panel load, of 5.0kPa, consistent with the previous hand calculations..

[Audio] Next, the column and middle strip bending moment apportionments, from the full tributary width effects, could be checked by clicking the Input dialog tab, then Loads, then, Lateral Distribution. Herewith, for this code, the column strip attracts 75% of the hogging moments, and 55% of the sagging moments..

[Audio] Next, define the inputs within the Input dialog tab, then Design Data, then Crack Control tab. Define the crack width calculations control as 0.30mm in general. However in this lesson, we shall not introduce a crack control mechanism, as RAPT would otherwise automatically add reinforcement, to ensure that the crack width magnitude specified, is not exceeded. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude the crack width control requirements..

[Audio] Next, define the deflection calculations control maximum value of I effective over I gross as 1.0, instead of the default 0.60. For the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude any maximum limit to the effective second moment of area of the slab section due to cracking..

[Audio] Next, for the purposes of this lesson, for us to benchmark against the other methods of design, we shall exclude shear enhancement at supports, and define the beam shear critical section at the face of the support itself. We shall also set the flexural critical section, i.e. the distance from the centre of the analytical support as zero, and not the face of the column support, so that the results are indeed read at the support peak, in accordance with the support location of the analytical model. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] The bending moment and shear force analysis results are obtained by choosing the Output dialog tab, then, Bending Moments, then, Load Combinations, then, Ultimate Design, then, Flexure, then, Graphics to display the slab bending moment and shear force diagrams, for the column and middle strips, respectively. For the load combination case 1.4G+1.6Q, the structural analysis results in a flat slab column strip hogging bending moment for the interior span of 1,463 kilo Newton metre, and a flat slab column strip sagging bending moment for the interior span of 535 kilo Newton metre, both figures being similar to that which is estimated by the hand method of calculation..

[Audio] The deflection analysis results are obtained by choosing the Output dialog tab, then, Deflections, then, All Spans Loaded, then, Graphics to display the total long term flat slab column strip deflection diagram. For the load combination case 1.0G+1.0Q, the structural analysis results in a total long term flat slab column strip deflection for the interior span of 11mm. Note that RAPT automatically calculates the long-term creep and cracked deflections, and thus, a manual slab stiffness modification is not necessary..

[Audio] The bending reinforcement design requirements are obtained by choosing the Output dialog tab, then, Flexural Design, then, Column Strip, then, Graphics, then Ultimate to display the required area of steel reinforcement for the 5,000mm flat slab column strip. Herewith, the required bending area of steel reinforcement A s, is shown as 10,417 millimetre squared, for the entire 5,000mm width of the flat slab column strip..

[Audio] Further bending design information can be obtained by choosing the Output dialog tab, then, Flexural Design, then, Column Strip, then, Graphics, then Service to display the flat slab column strip extreme fibre bending stresses. Herewith, the hogging bending tensile stress sigma b, is shown as -6.84Newton/mm2..

[Audio] Finally, the punching shear reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Punching. The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vc, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is EC2, chosen by selecting Input dialog tab, then, General, then, the Design Code and Material as EC2 (UK). Again, as before, the Top Reinforcement Axis Depth Limit is defined as, 400mm minus 345mm effective depth, d, yielding 55mm. Pattern Live Load is defined again as, No or crossed out. Not shown herewith, but again redefine the crack width calculations control as None, define the deflection calculations control maximum value of I effective over I gross as 1.0, exclude shear enhancement at supports, define the beam shear critical section at the face of the support itself, and set flexural critical section, i.e. the distance from the centre of the analytical support as zero. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] Again, the punching shear reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Punching. The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vRd,c, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are somewhat similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is ACI318 14, chosen by selecting Input dialog tab, then, General, then, the Design Code as ACI318 14 and Material as EC2 (UK) in order to maintain calculations in SI units. Again, as before, the Top Reinforcement Axis Depth Limit is defined as, 400mm minus 345mm effective depth, d, yielding 55mm. Pattern Live Load is defined again as, No or crossed out. Not shown herewith, but again redefine the crack width calculations control as None, define the deflection calculations control maximum value of I effective over I gross as 1.0, exclude shear enhancement at supports, define the beam shear critical section at the face of the support itself, and set flexural critical section, i.e. the distance from the centre of the analytical support as zero. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] Again, the punching shear reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Punching. The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Comparison is made of the computer results with respect to the previous hand calculations in terms of, the concrete shear strength, vRd,c, the area reduction, Ac, the effective punching shear force, V eff, the punching shear perimeter, u, the shear perimeter shear stress, v, and the required area of punching shear reinforcement, Asv. And so, all the input and output parameters are somewhat similar to that which is obtained by the hand method of calculation..

[Audio] The next selected design code of practice is AS3600 2018, chosen by selecting Input dialog tab, then, General, then, the Design Code as AS3600 2018 and Material as AS3600 2018. Again, as before, the Top Reinforcement Axis Depth Limit is defined as, 400mm minus 345mm effective depth, d, yielding 55mm. Pattern Live Load is defined again as, No or crossed out. Not shown herewith, but again redefine the crack width calculations control as None, define the deflection calculations control maximum value of I effective over I gross as 1.0, exclude shear enhancement at supports, define the beam shear critical section at the face of the support itself, and set flexural critical section, i.e. the distance from the centre of the analytical support as zero. We can then proceed to perform the structural analysis, by clicking the Run Analysis button..

[Audio] Again, the punching shear reinforcement design requirements are obtained by choosing the Output dialog tab, then, Shear Design, then, Punching. The flat slab column punching shear detailed calculations could then be investigated..

[Audio] Tabulated herewith is the comparison of effects and results from all the software, for all the presented codes of practice, showing good similarity between software, and the expected consistent variation across codes of practice..

[Audio] Note that for a like-for-like comparison, the effects had been generated for all codes based on the same load factors within the critical ULS loading combination case, and not code-specific load factors stipulated by the respective codes themselves..

[Audio] And so that completes this lesson where we have investigated how to design a reinforced concrete beam, including flat slabs, for shear resistance. That's it for this lesson, I will see you at the next one..