+承w立杆的稳定性计算:1•不考虑风荷载时,立杆的稳定性计算其中N——立杆的轴心压力设计值,N=14。35kN;0—轴心受压立杆的稳定系数,由长细比lO/i的结果查表得到0.26;i计算立杆的截面回转半径,i=1.58cm;l0计算长度(m),由公式l0=kuh确定,l0=2。60m;k―-计算长度附加系数,取1.155;1)对受弯构件:不组合风荷载组合凤荷载2)对轴心受压枸件:不组合凤荷載_甲/13曲03評广几组合风荷载+1.4x0.85(S囲十上列式中Sk、Sk―-永久荷载与可变荷载的标准值分别产生的内力和。对受弯构件内力为弯GkQk矩、剪力,对轴心受压构件为轴力;Sk――风荷载标准值产生的内力;f-—钢材强度设计Wk值;f—-钢材强度的标准值;W――杆件的截面模量;©――轴心压杆的稳定系数;A――杆k件的截面面积;0。9,1.2,1.4,|0。85|-—分别为结构重要性系数,恒荷载分项系数,活荷载分项系数,荷载效应组合系数;u0-9xI2x1.165亠卑—1+1J7T>组合风荷難叩1巨fhft_0,9x1.2x1.1652)对轴心受桂杆件$CA*0*91$0_土£耶[―.GfC£-rX0i85XLr4JQ.+2讥+加匚丿不组合凤荷载2・0…&.9K1.2XL165占册十0+95世[—_|利I+0.9(TT+g1]忌——材料强度分顼宰数,钢材为5.165^丫尙——分别均不组合和纲會风荷载时的结构抗力调整弟数勺根据懊新老规范安全度朮平■捞同的原则r井腥设新老规范采用的荷载和材斟强疫标准值相同,结掏抗力调整系数可恢下列公式计算,i)对受弯构件不组合凤荷载组台蚪荷载对于矍酉拘件,0.叫I及0.9林氐可近似取1.00:对受更杆件.09几及0.卯肌可近很取1.333,然庭将此系数的作用转化为立杆计算设度附抑系数衣二1.155予以琴虑.u—计算长度系数,由脚手架的高度确定,u=1.50;表5。3.3脚手架立杆的计算长度系数卩粪别立杆横距(m)连墙件布直二歩三跨=歩二跨収排架1.051.501.701.301.551.751.55l.uO1.80单排架^1.501.S02.00SGL+S»5,9X1.2xk165X上列武其中立杆的轴心压力设计A立杆净截面面积,A=4.89cm2;W——立杆净截面模量(抵抗矩),W=5。08cm3;口钢管立杆受压强度计算值(N/mm2);经计算得到口=111。83[f]钢管立杆抗压强度设计值,[f]=205.00N/mm2;不考虑风荷载时,立杆的稳定性计算b<[f],满足要求!2。考虑风荷载时,立杆的稳定性计算轴心受压立杆的稳定系数,由长细比入=l0/i的结果查表得到0.26;入值根据规范表进行查表得出,如下图:[f]钢管立杆抗压强度设计值,[f]=205.00N/mm2;表(:稳定系数d表」X01234567g901.0000.9970.9950.9920.9390.9S70.9S40.9810.9790.976100.9740.9710.9680.9SS0.9500.95S0.9550.9520.949200.9470.9440.9410.93S0.P360.9330.5300.9270.9240.921300.91E0.9150.9120.9090.P060.9030.S960.8930.SS9400.8860.8S208790.S750.E720.8580.E640.S610.8580.855500.8520.8490.8460.S430.S390.8360.B320.S290.8250.822600.31S0.S140.S100.3060.S020.7P70.7P30.7390.7840.779700.7750.7700.7650.7600.7550.7500.7440.7390.7330.728SO0.7220.71S0.7100.7040.6980.6920.^860.5800.6730.SS7900.6610.6540.6480.6410.6340.626o.eis0.6110.6030.595X012345巧1Sg1000.5880.5800.5730.5^0.5580.5510.5440.5370.5300.5231100.51S0.5090.5020.4960.4390.4830.4750.4700.4M0.45S1200.4520.4460.4400.4340.42S0.4230.4170.4120.4060.4011300.39e0.3910.3860.3810.3760.3710.3670.3620.3570.3531400.3490.3440.3400.3360.3320.3280.3240.3200.3160.3121500.3080.3050.3010.29E0.2940.2910.2870.2840.2S10.2771600.2740.2710.26S0.2650.2620.2590.2560.2530.2510.24S1700.2450.2430.2400.2370.2350.2329.2300.22^0.2250.2231300.2200.2180.2160.2140.2110.2090.2070.2050.2030.2011900.1990.1970.1950.1930.1910.1S90.1SSo.ise0.1S40.1B22000.1S00.1790.1770.1750.1740.1720.1710.1650.1570.1^62100.1640.1630.1610.1600.15P0.1570.1550.1540.1530.1522200.1500.1490.1480.1460.1450.1440.1430.1410.1400.1392300.1380.1370.1360.1350.1330.1320.1310.1300.1290.12S2400.1270.12^0.1250.1240.1230.1220.1210.1200.1190.11S2500.117注:当A,>250时,i=732O/Xs;i—计算立杆的截面回转半径,i=1.58cm...