簡支梁橋設(shè)計計算

1、T形簡支梁橋設(shè)計名稱：天河簡支梁設(shè)計設(shè)計資料及構(gòu)造布置橋面跨徑及橋?qū)捲瓌t跨徑：該橋為二級公路上日勺一座簡支梁橋，根據(jù)橋下凈空和方案日勺經(jīng)濟比較， 擬定主梁采用原則跨徑為20m勺裝配式鋼筋混凝土簡支梁橋。計算跨徑：根據(jù)梁式橋計算跨徑勺取值措施，計算跨徑取相鄰支座中心間距為 19.5m.橋面寬度：橫向布置為凈一7 （行車道）+2X0.75m （人行道）+2X0.25 （欄桿）橋下凈空：4m混凝土：主梁采用C25主梁高：取1.5m.主梁梁肋寬：為保證主梁抗剪需要，梁肋受壓時勺穩(wěn)定，以及混凝土勺振搗質(zhì)量，一般梁肋寬度為15cm18cm，鑒于本橋跨度16m按較大取18cm設(shè)計根據(jù)（1） 公路橋涵設(shè)計通用

2、規(guī)范（JTGD60-）（2）公路鋼筋混凝土預(yù)應(yīng)力混凝土橋涵設(shè)計規(guī)范（JTGD62-）（3）橋梁工程（4）橋梁工程設(shè)計措施及應(yīng)用3荷載橫向分布系數(shù)計算書3.1主梁荷載橫向分布系數(shù)計算3.1.1跨中荷載橫向分布系數(shù)a.計算主梁日勺抗彎及抗扭慣性矩IX和ITX運用G-M法計算荷載橫向分布系數(shù)，求主梁截面勺形心位置ax平均板 厚為：一 1 一 ，一 h= (h 薄+h 膏)=0.5X(13+8)=1O.5cm12 薄 厚則 ax= (180-15)X10.5X(10.52) +15X150X(150：2) / (180-15) X 10.5+15X150 =44.7cmI = X(180-15) X1

3、0.53+(180-15) X 10.5X(44.7-105)2+上 X15X1503+15XX 12212150 c_150X(44.7-)2=4.99X106 cm4T 形截面抗扭慣性矩 Itx=1.15X 3 X(1.8-0.15) X0.1053+1.5X0.153 =2.67X10-3 m4則單位抗彎及抗扭慣性矩：j = J = 4.、10 -2 = 2.77 x 10-4 m4/cmX b 180J = x =267 x =1.48 x 10-5 m4/cmTX b 180b.計算橫梁日勺抗彎及抗扭慣性矩Iy和ITyl=4b=4X 180=720 cmct； X (480-15)=

4、232.5 cm3h，=150X： =112.5cm 取整 110 cm4b，=15 cm由 c/l=232.5/720=0.32 查得入 /c=0.608則入=0.608X232.5=141.4 cm=1.41m求橫隔梁截面重心位置：ay= 141X10.52+(12) X15X1102 /2X141X10.5+110X15=23.1cm橫梁抗彎慣性矩：I= X 2 X 141 X 10.53 + 2 X 141 X 10.5 X (23.1-10.5 )2+ X15X1103+15X y 12212110 X (23.1-110/2)2=4.31 X 106 cm4=4.31 X 10-2

5、 m4 1oocoITy=1.15X - X(2X141.4X 103 +110X 153)=2.6X 105 cm3單位抗彎慣性矩和抗扭慣性矩為：場J =業(yè)=4.31 *106 =0.9 X 104 cm4/cmy b 4801I =1 = 2.6 6105 =542 cm4/cmTy b 4801計算抗彎參數(shù)。和抗扭參數(shù)a0= B J =擋 |2.77x104 =0.2451 Jy 1954 0.9 x104取 G=0.43E，則:=0.027a_ G(J璞 + J )_ 0.43(1.48x103 + 542)=0.0272E JJy22.77 x104 x0.9x104和 f 0.02

6、7 =0.164計算荷載彎矩橫向分布影響線坐標(biāo)已知0 =0.245，查G-M法圖表下表數(shù)值梁位荷載位置B3B/4B/2B/40-B/4-B/2-3B/4-B校 核K000.900.960.991.061.081.060.990.960.908B/41.71.531.321.21.040.860.630.430.227.97B/22.482.111.731.380.990.650.27-0.15-0.527.963B/43.282.712.11.530.970.41-0.14-0.62-1.818.01B43.32.481.70.90.22-0.53-1.18-1.857.97K100.970.

7、9811.031.041.0310.980.978.03B/41.041.051.061.061.010.980.950.900.887.97B/21.171.141.11.0510.970.910.860.828.033B/41.31.251.151.060.990.90.850.780.727.99B1.481.31.191.050.960.880.810.750.708.03實際梁位與表列梁位關(guān)系圖對于號梁來說:K= K 3B4對于號梁來說:K= KB4列表計算各主梁荷載橫向分布影響線坐標(biāo)值:梁號計算式荷載位置B3B/4B/2B/40-B/4-B/2-3B/4-BK= K 產(chǎn)1.31.2

8、51.151.060.990.90.850.780.72號K = K 產(chǎn)43.282.712.11.530.970.41-0.14-0.62-1.18=K -K-1.98-1.46-0.95-0.470.020.490.991.41.9五-0.32-0.24-0.16-0.08-0.0030.080.160.230.31Ka=K +a L0a2.962.471.941.450.970.490.02-0.39-0.87氣.=Ka/40.740.620.490.360.240.120.005-0.1-0.22號K，j K 產(chǎn)41.041.051.061.061.010.980.950.90.88K

9、o=K 0 :1.71.531.321.21.040.860.630.430.22=K 1-K-0.66-0.48-0.26-0.14-0.030.120.320.470.66&-0.11-0.08-0.04-0.02-0.0050.020.050.080.11Ka=K0+疝1.591.451.281.181.040.880.680.510.33門廣Ka/40.400.360.320.2950.260.220.170.130.08繪制荷載橫向分布影響線，求跨中截面日勺荷載截面日勺荷載橫向分布系數(shù)根據(jù)公路橋涵設(shè)計通用規(guī)范(JTG D60)規(guī)定，汽車荷載距人行道邊沿 距離不不不小于0.5m。針對各主梁進行荷載最不利位置布置，計算各主梁荷載橫 向分布系數(shù)見下圖履 CI-?履 CI-?各梁橫向分布系數(shù)如下:, 0.66 + 0.403 m1 汽=(、, 0.227 - 0.007)+ ()=0.642人群荷載:叫汽=(0.373 + 0.30320.256