板式樓梯的計算

,撓度驗算,,,,,,,,,,

,,,,,,,,2023年3月18日,,,

基本信息,,,,,,,,,,,

計算跨度L0=,1750,mm,,允許撓度值[αf]=L0/,,,200,=,8.75,,

砼強度等級C,25,抗拉強度標準值ftk=,1.78,N/mm*mm,,,,,,,

,,砼彈性模量Ec=,28,kN/mm*mm,,,,,,,

縱向受拉鋼筋強度等級,1,鋼筋彈性模量Es=,200,kN/mm*mm,,,,,,,

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截面形式是？,矩形,YES,,保護層厚度as=,,20,mm,,有效高度h0=,80,mm

,,截面寬度b=,1000,mm,,5,根直徑,10,受拉鋼筋As=,392.70,mm*mm

,,截面高度h=,100,mm,,0,根直徑,0,受壓鋼筋A's=,0.00,mm*mm

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,T形或I形,NO,,保護層厚度as=,,25,mm,,有效高度h0=,475,mm

,,截面腹板厚度b=,300,mm,,6,根直徑,25,受拉鋼筋As=,2945.24,mm*mm

,,截面高度h=,500,mm,,0,根直徑,25,受壓鋼筋A's=,0.00,mm*mm

,,受拉翼緣寬度bf=,0,mm,受壓翼緣寬度b`f=,,,500,mm,,

,,受拉翼緣高度hf=,0,mm,受壓翼緣高度h`f=,,,100,mm,,

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按標準組合（荷載短期效應組合）計算的跨中彎矩Mk=,,,,,,5.293307207,kN*m,活載準永久值系數=,,0.3,

按準永久組合（荷載長期效應組合）計算的跨中彎矩Mq=,,,,,,4.355416582,kN*m,,,,

短期剛度Bs,,,,,,,,"Yeah,Let'sEnjoyit!*_*",,,

受拉鋼筋應變σss=Mk/(0.87*h0*As)=,,,193.67,N/mm*mm,,,,,,,

有效受拉混凝土截面面積Ate=,,,50000,mm*mm,,,,,,,

有效配筋率ρte=As/Ate=,,,0.0079,,,,,,,,

鋼筋應變不均勻系數ψ=1.1-0.65ftk/(ρte*σss)=,,,0.34,,ψ修正得,0.40,,,,,

αE=Es/Ec=,,,7.14,,,,,,,,

受拉鋼筋配筋率ρ=As/b*h0=,,,0.00,,,,,,,,

T形或I形受壓翼緣面積與腹板有效面積之比值γ`f=(b`f-b)*h`f/(bh0)=,,,0.00,,,,,,,,

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短期剛度Bs=EsAs（h0*h0）/[1.15ψ+0.2+6αEρ/(1+3.5γ`f)]=,,,5.78E+11,N*mm*mm,,,,,,,

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長期剛度Bl,,,,,,,,,,,

荷載長期作用下的撓度增大影響系數θ=2-0.4ρ`/ρ=,,,2.00,,,,,,,,

長期剛度Bl=MkBs/[Mq(θ—1)+Mk]=,,,3.16826E+11,N*mm*mm,,,,,,,

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撓度αf=5Mk（L0*L0）/(48Bl)=,,,5.33,mm,,,,,,,

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