鋼管支撐強度及穩(wěn)定性驗算

鋼支撐計算（斜撐）,,,,,,,,,,,注意全國規(guī)程JGJ120-2012與地方規(guī)程輸入?yún)^(qū)別

鋼支撐軸力標(biāo)準(zhǔn)值N標(biāo)=,,1547,KN，,L=,13.7,m,,,25.848,,輸入圍護(hù)結(jié)構(gòu)計算軟件支撐計算軸力標(biāo)準(zhǔn)值

,,,,,,,,,,,,

一、計算參數(shù),,,,,,,,,,,

分項系數(shù)=,,1.25,,,按,1.25,,,,,《全國規(guī)范》第4.2.3

"初始偏心矩e0=max(0.001*L,0.04)=",,0.04,m,,按,0.04,,,,,新版基坑規(guī)程要求

支撐面均布荷載q0=,,2,Kpa,,,,,,,,可取2Kpa，《上海規(guī)范》取4Kpa

支撐最大設(shè)計軸力N=,,1933.75,KN,,,,,,,,

質(zhì)量密度ρ=,,7850,Kg/m3,,,78.5KN/m3,,,,,

初始彎矩M0=,,104.340487,KN·m,,由自重及支撐面均布荷,,,,,,

偏心彎矩Me=,,77.35,KN·m,,,,,,,,

最大彎矩M=Me+M0=,,181.690487,KN·m,,彎矩作用平面內(nèi)的軸心受壓構(gòu)件穩(wěn)定,,,,,,

穩(wěn)定系數(shù)Ф=,,0.778155526,,,,,,,,,

截面塑性發(fā)展系數(shù)γ=,,1.15,,,鋼管截面系數(shù)，b類構(gòu)件,,,,,,《鋼結(jié)構(gòu)》5.2.1

鋼管外徑D=,,0.609,m,,,,,,,,

鋼管內(nèi)徑d=,,0.577,m,,,,,,,,

截面慣性矩I=Л（D4-d4）/64=,,0.001311173,m4,,,,,,,,

截面模量W=2*I/D=,,0.004305987,m3,,在彎矩作用平面內(nèi)對較大受壓纖維,,,,,,

截面回轉(zhuǎn)半徑i=（D2+d2）0.5/4=,,0.209733462,m,,,,,,,,

截面積A=Л（D2-d2）/4=,,0.029807431,m2,,,,,,,,

彈性模量E=,,2.06E+05,Mpa,,Q235鋼,,,,,,

構(gòu)件計算長度修正系數(shù)μ=,,1,,,,,,,,,《全國規(guī)范》第4.5.2

構(gòu)件長細(xì)比λ=μ*L/i=,,65.32100258,,<,150,,,,,,《建筑基坑支護(hù)技術(shù)規(guī)程》4.9.14-2

λ*SQRT（fy/235）,,65.32100258,,,,,,,,,

等效彎矩系數(shù)βmx=,,1,,,無端彎矩但有橫向荷載作用,,,,,,《鋼結(jié)構(gòu)》5.2.2.1

參數(shù)Nex=Л2*EA/（1.1λ2）=,,12911.98828,KN,,,,,,,,《鋼結(jié)構(gòu)》5.2.2.1

二、鋼支撐強度驗算,,,,,,,,,,,

f=N/A+M/（γ*W）=,,101.565941,Mpa,<,[f]=215MPa,滿足要求,,,,,

三、鋼支撐整體穩(wěn)定性驗算,,,,,,,,,,,

1、鋼支撐豎向平面內(nèi)的穩(wěn)定性驗算,,,,,,,,,,,

f1=N/（Ф*A）=,,83.36991894,Mpa,,,,,,,,

f2=βmx*M/[γ*W*（1-0.8*N/Nex）]=,,41.68557388,MPa,,,,,,,,

f=f1+f2=,,125.0554928,MPa,<,[f]=215MPa,滿足要求,,,,,

2、鋼支撐豎向平面外的穩(wěn)定性驗算,,,,,,,,,,,《鋼結(jié)構(gòu)》5.2.2.2

構(gòu)件長細(xì)比λ=μ*L/i=,,97.98150387,,<,150,,,,,,

λ*SQRT（fy/235）,,97.98150387,,,,,,,,,

平面外的軸心受壓穩(wěn)定系數(shù)Фy=,,0.568085581,,,,,,,,,

f1=N/（Фy*A）=,,114.198926,MPa,,,,,,,,

截面影響系數(shù)η=,,0.7,,,閉口截面取0.7,,,,,,

等效彎矩系數(shù)βtx=,,1,,,無端彎矩但有橫向荷載作用,,,,,,

均勻彎曲的受彎構(gòu)件整體穩(wěn)定系數(shù)Фb=,,1,,,閉口截面取1.0,,,,,,

f2=η*βtx*Mx/(Фb*W1x)=,,12.57435344,MPa,,,,,,,,

f=f1+f2=,,126.7732794,MPa,<,[f]=215MPa,滿足要求,,,,,

,,,,,,,,,,,,

圓管截面的受壓構(gòu)件，其外徑與壁厚之比不應(yīng)超過100(235/fy),,,,,,,,,,,

D/t=,38.0625,<=,100,,,,,,,,《鋼結(jié)構(gòu)》10.1.2

,,,,,,,,,,,,

b類軸心受壓構(gòu)件的穩(wěn)定系數(shù)計算,,,,,,,,,,,

Q235鋼fy=,,,235,Mpa,,,,,,,

彈性模量E=,,,206000,MPa,,,,,,,

λn=λ*(fy/E)0.5/Л=,,,0.702268676,,,,,,,,《鋼結(jié)構(gòu)》10.1.2附表C-4注1

Фx=,,,0.778155526,,,,,,,,《鋼結(jié)構(gòu)》10.1.2附表C-4注1

α1=,,,0.65,"b類構(gòu)件

（焊接鋼管）",,,,,,,《鋼結(jié)構(gòu)》10.1.2附表C-5

α2=,,,0.965,,,,,,,,

α3=,,,0.3,,,,,,,,

,,,,,,,,,,,,

,,,,,,,,,,,,

注：,藍(lán)色部分填入,,,,,,,,,,

,粉色部分需與規(guī)范確認(rèn),,,,,,,,,,

,紅色部分為計算結(jié)果與[f]比較,,,,,,,,,,

,,,,,,,,,,,,

圓管截面的受壓構(gòu)件，其外徑與壁厚之比不應(yīng)超過100(235/fy),,,,,,,,,,,

D/t=,38.0625,<=,100,,,,,,,,

,,,,,,,,,,,,

b類軸心受壓構(gòu)件的穩(wěn)定系數(shù)計算,,,,,,,,,,,

Q235鋼fy=,,,235,Mpa,,,,,,,

彈性模量E=,,,206000,MPa,,,,,,,

λn=λ*(fy/E)0.5/Л=,,,1.053403014,,,,,,,,

Фx=,,,0.568085581,,,,,,,,

α1=,,,0.65,"b類構(gòu)件

（焊接鋼管）",,,,,,,

α2=,,,0.965,,,,,,,,

α3=,,,0.3,,,,,,,,