Z Purlin Design

Z Purlin???Created by Madurai ES Consultancy Services Pvt LtdPageDESIGN OF Z PURLINSCreated By: GAUTAM PAULPurlin DesignationP1JOB No.:ProjectShree AmanDATE :02-07-2014Input Data: Purlin GeometrySpan of the purlin=7.500MSpacing of the purlin=1.5MNo. of Sag rods=2Slope of the Roof=6deg.Number of Spans=12(for 1 or 2 spans, Bending Moment Coefficient is 8, for 3 or more spans, it is 10)(in case of Bending about minor axis, (No of spans)x(No of sagrods+1) is used.Input Data: LoadsDead LoadsWeight of Sheeting=13kg/sqmSelf Weight of Purlin=Automatically Calculated from Section propertiesExtra for cleats, as % of Purlin weight=10%Additional Dead Loads to Consider=0kg/sqmLive LoadsLive load on Roof=Automatically Calculated from Slope=75kg/sqmAdditional Live Loads to be considered=0kg/sqmWind LoadsBasic Wind Speed39m/sTerrain Category3k11Maximum Horizontal Dimension of Building90.65mk31Hence, Bldg ClassCHeight of Top6.548mBased on the data on right, k2 is obtained from the tablesk20.82Ht of building at eaves level, h=7mWidth of the building, w=30.5mLength of the Building, l=90.65mHence, h/w=0.230and l/w=2.972Based on the h/w and l/w, the values of Cpe is obtained from tables as noted below:Maximum Downward Cpe (include sign)0Maximum Upward Cpe (include sign)-0.9Based on % of openings, Cpi is taken as +/-0.2Input Data: Purlin Section Being CheckedTryZ 200x80x2.5Yield stress of material3450KG/CM2assumed since not given in catalogueFlange Width, b80mmDepth of section d200mmThickness t2.5mmApproximate Geometric PropertiesLength of Lip lip_l20mmAssumed Vertical Lips and Bending Radius disregardedInner Bending Radius3mmassumedEach Lip Area43.75sqmmEach Flange Area200sqmmArea9.75cm2Web Area487.5sqmmZxx69.47cm3Section Modulus about Major AxisZyy6.71cm3Section Modulus about Minor AxisTotal Area9.75cm2Ixx694.71cm4Moment of Inertia about Major AxisZxx69.47cm3Iyy52.87cm4Moment of Inertia about Minor AxisZyy6.71cm3Ixx total694.71cm4Purlin Weight5.103kg/sqmIyy total52.87cm4Output SummarySection Properties OK?not OKBased on IS 801 Clause 5.2.2.1Stresses Ok?OKCritical Stress Factor0.98Deflection Check OK?OKHence, Overall:NOT OK

Z Purlin Design ReportPrepared By Gautam PaulProject : Shree AmanDesign Code refferedBasic Design with checks for Stresses and Deflection based on IS 800 onlyAdded Section property checks and Allowable Stress Calculations based on IS 801JOB No.:0DATE :2-7-14Input Data: Purlin GeometrySpan of the purlin=7.500MSpacing of the purlin=1.5MNo. of Sag rods=2Slope of the Roof=6deg.Number of Spans=12Bending Moment Coefficients: Use 8 for Single/Two spans, 10 for 3 or more spansBending Moment Coefficient for Mxx10For Bending About Minor Axis, Number of spans= number of spans x (number of sagrods+1)Number of Spans about Minor Axis=36Bending Moment Coefficient for Myy10Cross Sectional Area of Purlin9.75cm2Purlin Weight=7.654kg/m(Area in sqcm x 0.785 kg/sqcm/m) in kg/m=5.103kg/sqm(Weight in kg/m)/spacingDesign Calculations: Primary Load CasesDEAD LOADWeight of Sheeting13.000kg/sqmSelf Weight of Purlin (calculated above)5.103kg/sqmExtra load for weight10% of purlin weight0.510kg/sqmOther Dead Loads0.000kg/sqmTotal Dead Load18.613kg/sqm=0.186kN/sqmLIVE LOADLive Load on Roof = 75 kg/sqm if slope is less than 10 degrees. If Slope is more than 10 degrees, LL = 75 2x(slope-10), subject to minimum of 40 kg/sqmLive load on Roof=75KG/M2Additional Live Loads to be considered=0KG/M2Total Live Load75kg/sqm=0.750kN/sqmWIND LOADBasic Wind Speed Vb39m/sk11k31Terrain Category3Maximum Horizontal Dimension of Building90.65mHence, Building Class isCHeight of Top6.548mBased on the above data, k2 is obtained from the tablesk20.82Design Wind Speed Vz=k1.k2.k3.Vb31.98m/sDesign Wind Pressure pz=0.6Vz^2613.632N/sqm=0.614kN/sqmHt of building at eaves level, h=7mWidth of the building, w=30.5mLength of the Building, l=90.65mHence, h/w=0.230and l/w=2.972Based on the h/w and l/w, the values of Cpe is obtained from tables as noted below:Maximum Downward Cpe (including sign)0Maximum Upward Cpe (including sign)-0.9Based on % of openings, Cpi is taken as +/-0.2Wind Load is included in two load combinations DL+WL and DL+LL+WLSince, Dead Load and Live Load are downward, DL+WL will be critical for the maximum upward wind forceSimilarly, DL+LL+WL will be critical for the maximum downward wind forceWL1: Maximum Upward Wind Force To be used in combination DL+WL1Maximum Upward Cpe (including sign)-0.9Cpi to use (for upward, use -)-0.2Hence, Cpe+Cpi =-1.1Design Wind Pressure pz0.614kN/sqmWind pressure for Purlin Design-0.675kN/sqmWL2: Maximum Downward Wind Force To be used in combination DL+LL+WL2Maximum Downward Cpe (including sign)0Cpi to use (for upward, use -)0.2Hence, Cpe+Cpi =0.2Design Wind Pressure pz0.614kN/sqmWind pressure for Purlin Design0.123kN/sqmDesign Calculations: Primary Load Cases Conversion of forces to Normal And Tangential ComponentsSpacing of the purlin=1.5mSlope of the Roof=6degreesTotal Dead Load=0.186kN/sqmDL Normal Component = DL x Spacing x cos(slope) =0.278kN/mDL Tangential Component = DL x Spacing x sin(slope) =0.029kN/mTotal Live Load=0.750kN/sqmLL Normal Component = LL x Spacing x cos(slope) =1.119kN/mLL Tangential Component = LL x Spacing x sin(slope) =0.118kN/mTotal Wind Load in WL1=-0.675kN/sqmWL is normal to roofHence, WL1 normal component = WL1 x Spacing =-1.012kN/mAnd, WL1 Tangential component =0kN/mTotal Wind Load in WL2=0.123kN/sqmWL is normal to roofHence, WL2 normal component = WL2 x Spacing =0.184kN/mAnd, WL2 Tangential component =0kN/mDesign Calculations:Summary of Loads in Load CombinationsFrom above calculations, the components of load in the various load combinations are tabulatedDL+LLDL+WL1DL+LL+WL2Normal Load1.396-0.7351.581kN/mTangential Load0.1470.0290.147kN/mFor Strength Design, 0.75 factor is applicable for combinations with Wind Load since 33.33% extra stress is allowedHence, the components of load in the various load combinations for Strength design areDL+LL0.75(DL+WL1)0.75(DL+LL+WL2)Normal Load1.396-0.5511.185kN/mTangential Load0.1470.0220.110kN/mMaximum Normal Component =1.396kN/mPurlin Section Selected:Section NameZ 200x80x2.5Yield stress of material3450kg/sqcmFlange Width, b80mmDepth of section d200mmThickness t2.5mmLength of Lip lip_l20mmInternal Bending radius3mmTotal bending Radius, rad5.5mmFlange Width w/o bend, w = b 2 x rad69mmArea9.75cm2Zxx69.47cm3Zyy6.71cm3Ixx694.71cm4Iyy52.87cm4Purlin Weight=7.654kg/m(Area in sqcm x 0.785 kg/sqcm/m) in kg/m=5.103kg/sqm(Weight in kg/m)/spacingDesign Calculations: Checking Basic Section Properties based on Section 9 of BS:5950 Part 5 1998Check No. 1 Overall Depth =L/45Overall Depth200mm100t =250mmL/45 =166.667mmHenceOKCheck No. 2 Overall Width of Compression Flange= b/5Width of Lip20mmB/5 =16mmHenceOKCheck No. 4 Total Width over both flanges >= L/60Total Width over both flanges157.5mmL/60 =125.000mmHenceOKCheck No. 5 Zxx of Purlin >= WL/1400 for Simply Supported Purlin and >=WL/1800 for Continuous PurlinZxx=69.47cm3W is normal component of unfactored distributed dead load plus imposed load in kNL is span of purlin in mmW =10.474kNL =7500mmNumber of Spans=12Hence, denominator =1800WL/denominator43.641HenceOKResult 1: Check for Section Properties Based on BS 5950 Part 5 Sec.9:OKDesign Calculations: Checking Basic Section Properties based on IS 801 for Lip of PurlinMinimum Depth of Lip shall be 2.8 x t x ((w/t)^2-281200/Fy)^(1/6) and not less than 4.8tt=2.5mmw=69mmFy=3450kg/sqcmw/t=27.62.8 x t x ((w/t)^2-281200/Fy)^(1/6)20.759mm4.8t=12mmLip l=20mmHenceNOT OKLip is Edge stiffener only if w/t