Sheet1TIMBER TRUSS DESIGNPROJECT:schoolSITE:hospital hillJOB NO.:1DESIGNED BY:MURIITruss Reference:T1No. ofTrusses:4GENERAL DESIGN INFORMATION:Battens/PurlinsRoof Pitch (degrees)=22.5spacing (mm) c/c=330Truss Span (mm), L =6200TRIAL MEMBER SIZES (mm)Truss Spacing (mm), ts=1800depth (d)width (b)Eaves Projection (mm), Lp=600Top Chord (rafter)10050Bottom Chord10050GENERAL LOADING:Webs10050Option NogradeTimber/gradeRafter Level:1CSScypress / ss gradeImposed Load (N/m^2)=2502CGScypress / gs gradeDead Load (on slope) (N/m^2)=1503PSSpine / ss grade(tiles,gci,etc)4PGSpine / gs gradeCeiling Level:Choose timber/grade option No.Imposed Load (N/m^2)=100Top chordBottom ch.WebsDead Load (N/m^2)=150Option No.111Tank Capacity=270Litres (tank load distributed over three trusses by spreader beams)Nail diameter (mm) to be used (2.65,3.0 or 3.35) :-2.65Design Results check:Deflection:DEFLECTION OKDesign Stress:DESIGN STRESS OKThe member force factors are based on tables given in the "TIMBER DESIGNERS MANUAL"by Ozelton and Baird (second edition).ANALYSIS RESULTS:MemberMemberForceFactorMemberNo.Length(mm)"rafter""ceiling"Force(kN)AngleDegrees116783.9202.6138.11622.5216783.2672.6137.36577.632067-3.621-2.414-7.49751.242067-2.414-1.611-5.00028.758240.9630.0001.108106.361648-0.963-1.301-2.90376490.0000.0000.000Note:-Compression= +veTension= -veheight from C/tie,h=1388mmOverall height, H=1641mmReactions (kN):Minimum bearing width required :R1=R2=4.779C/tie for 100mm w/plate=16mmMin w/plate width req.:32mmTimber Volume (m^3)=0.096Truss Weight (kg)=48Member Results Summary:Member No.Axial ForceShear (N)Moments (Nm)(N)end 1end 2end 1maxend 218116453755130-253-25327365755453-253-25303-74974927380-254-2544-5000615615-254-254-254511086-29037004320130130DESIGNDesign calculations are in accordance with BS 5268: Part 2:1991.yzzdybRectangular timber members subject to axial load and bending about zz-axisMember No.EffectiveRadius ofSlendernessLength(Leff)gy. r(mm)Leff/rNo load sharing1134228.946.49Load share factor,K8 =12134228.946.49load duration ,K3 =1.253(medium term loading)4574228.925.696Member No.Grade stressesApplied stressesaxialbendingshearaxialbendingshear17.007.101.101.6230.0030.22627.007.101.101.4730.0030.22634.307.101.101.4990.0030.22144.307.101.101.0000.0030.18557.007.101.100.2220.0000.00064.307.101.100.5810.0000.00077.101.100.0000.0020.130Member No.Permissible stressesMaximum Stress FactorsaxialbendingshearAxialBendingTotal16.2310.021.380.26054016220.00030353220.260843694426.2310.021.380.2364225320.00030353220.236726064236.0710.021.380.24721111410.00030458260.247515696746.0710.021.380.1648832490.00030458260.165187831657.4210.021.380.029862893100.029862893166.0710.021.380.095732435100.0957324351710.021.3800.00015528680.0001552868Deflections (mm)(calculated deflections multiplied by 1.25 to allow for long term creep effectsas stipulated in BS5268 part 3.)JointVerticalHorizontal10028.4007048.13890MaximumAllowabledeflection=8.401mmdeflection=18.600mmDeflection:DEFLECTION OKDesign Stress:DESIGN STRESS OKNAILS AND NAILPLATE CALCULATIONSNails required on each face (count left to right)NodeChordsWebsPlate size (mm)11615100x2182826100x165322100x1244151566130x281Splice joints (if necessary depending on timber stock lengths available)Nails requiredPlate size (mm)Bottom chord (ceiling tie) -member No.41010100x209Top chord (rafter) -member No.21515100x261TIMBER CUTTING LIST (sizes in mm and angles in degrees)Rafter 7-1-2size67.5db10050x=67.5Lc=4005Lo=4046Ceiling tie 3-4-3sizedb10050x=22.5Lc=5959Lo=6200Web 5sizedb10050x=73.7Lc=721Lo=746y=102.4Wed 6sizedb10050x=28.7Lc=1532Lo=1572y=51.2t=38.8Notes:1. Nail plates to be galvanized steel plates of 0.9mm minimum thickness.2. Timber to be graded to the specifications of KS02 - 771 standard.3. Timber moisture content to be below 14% or at equilibrium M.C at the time of trussfabrication.000100000LOAD FACTORS(RAFTER LEVEL)MEMBERPITCH123456155.7964.83-5.6-3.7331.197-1.19717.54.9884.157-4.757-3.1711.092-1.092204.3863.655-4.121-2.7471.018-1.01822.53.923.267-3.621-2.4140.963-0.963253.5492.957-3.217-2.1450.922-0.92227.53.2492.708-2.881-1.9210.891-0.8913032.5-2.598-1.7320.866-0.86632.52.7922.327-2.354-1.5690.846-0.846352.6152.179-2.142-1.4280.831-0.831CEILING LEVELPITCH123456153.8643.864-3.732-2.4880-1.59517.53.3263.326-3.172-2.1150-1.455202.9242.924-2.748-1.8320-1.35622.52.6132.613-2.414-1.6110-1.301252.3662.366-2.145-1.4280-1.2327.52.1662.166-1.921-1.2830-1.1873022-1.732-1.1550-1.15532.51.8611.861-1.57-1.0480-1.128351.7431.743-1.428-0.9480-1.109Member forces due to unit load at:CeilingApexmemberCeilingApexACTUALA(mm^2)E(N/mm^2)FUL/AEFUL/AE12.612.618.116500040000.00180.001822.612.617.365500040000.00160.00163-2.41-2.41-7.497500040000.00190.00194-1.61-2.41-5.000500040000.00080.001250.000.0001.108500040000.00000.00006-2.610.000-2.903500040000.00060.0000SUM0.00670.0065Grade stressestimbergradebending //tensionCompress.N/mm^2shearMOEN/mm^2per //per //perpper //MeanMinCYPRESSSS7.14.371.81.182004000GS5361.61.174003600PINESS4.32.64.31.10.9118004300GS31.83.610.9106003900K12 factorLe/r