瀝青路面設(shè)計(jì)計(jì)算實(shí)例

1、瀝青混凝土路面計(jì)算書一、軸載分析路面設(shè)計(jì)以雙輪組單軸載100kN 為標(biāo)準(zhǔn)軸載。1.以設(shè)計(jì)彎沉值為指標(biāo)及驗(yàn)算瀝青層層底拉應(yīng)力中的累計(jì)當(dāng)量軸次3）軸載換算：kPi4.35軸載換算的計(jì)算公式： N=C1C2ni ( P )i 1計(jì)算結(jié)果列于下表：車型Pi （kN）C1C2ni （次 /日）C1C2 ni ( Pi ) 4.35 （次 /日）23.7016.4P東風(fēng) EQ140前軸后軸69.2011553111.48解放 CA10B前軸19.4016.4后軸60.85113041.5350.45黃河 JN150前軸49.0016.4后軸101.6011395423.24kPi )4.35N=C1C2n

2、i (885.38i 1P注：軸載小于 25kN 的軸載作用不計(jì)。2）累計(jì)當(dāng)量軸次：根據(jù)設(shè)計(jì)規(guī)范，二級(jí)公路瀝青路面的設(shè)計(jì)年限取 15 年，雙車道的車道系數(shù)取 0.6 累計(jì)當(dāng)量軸次：1t36515.4%1513651N e'N15.4%×885.380.6=4312242（次）3）驗(yàn)算半剛性基層層底拉應(yīng)力中的累計(jì)當(dāng)量軸次（ 1）軸載換算，結(jié)果列于下表：車型Pi （kN） C1C2ni （次 /日）C1C2ni ( Pi )8 （次 /日）東風(fēng) EQ14069.2011553P后軸解放 CA10B后軸60.85113041.557.17黃河 JN150后軸101.60113954

3、48.48kN=C1C2ni ( Pi )8505.65i 1P注：軸載小于 50kN 的軸載作用不計(jì)驗(yàn)算半剛性基層層底拉應(yīng)力的軸載換算公式：kPi )8N= C1C2ni (i 1P（2）累計(jì)當(dāng)量軸次：t1365115136515.4%N e'N1 =5.4%×505.65 0.6 =2462767.6（次）二、結(jié)構(gòu)組合與材料選取根據(jù)規(guī)范推薦結(jié)構(gòu)，并考慮到公路沿途筑路材料較豐富，路面結(jié)構(gòu)采用瀝青混凝土（ 15cm），基層采用二灰碎石（ 20cm），基底層采用石灰土（厚度待定） 。二級(jí)公路面層采用三層式瀝青面層，表面層采用細(xì)粒式密級(jí)配瀝青混凝土（厚度 3cm），中間層采用中粒

4、式密級(jí)配瀝青混凝土（厚度 5cm），下層采用粗粒式密級(jí)配瀝青混凝土（厚度 7cm）。三、各層材料的抗壓模量與劈裂強(qiáng)度抗壓模量取 20的模量，各值均取規(guī)范給定范圍的中值，因此得到20的抗壓模量：細(xì)粒式密級(jí)配瀝青混凝土為1400MPa，中粒式密級(jí)配瀝青混凝土為1200MPa，粗粒式密級(jí)配瀝青混凝土為1000MPa，二灰碎石為1500MPa，石灰土為550MPa。各層材料的劈裂強(qiáng)度：細(xì)粒式密級(jí)配瀝青混凝土為1.4MPa，中粒式密級(jí)配瀝青混凝土為1.0MPa，粗粒式密級(jí)配瀝青混凝土為0.8MPa，二灰碎石為0.5MPa，石灰土為0.225MPa。四、土基回彈模量的確定該路段處于 區(qū)，土基回彈模量為30

5、MPa。五、設(shè)計(jì)指標(biāo)的確定對(duì)于二級(jí)公路，規(guī)范要求以設(shè)計(jì)彎沉值作為設(shè)計(jì)指標(biāo)，并進(jìn)行結(jié)構(gòu)層底拉應(yīng)力驗(yàn)算。1.設(shè)計(jì)彎沉值。路面設(shè)計(jì)彎沉值計(jì)算：該公路為二級(jí)公路，公路等級(jí)系數(shù)取 1.1，面層是瀝青混凝土，面層類型系數(shù)取 1.0，半剛性基層、底基層總厚度等于或大于 20cm，基層類型系數(shù)取 1.0.設(shè)計(jì)彎沉值為：Ld600N e0.2 Ac Ab As6004312242 0.2 1.1 1.0 1.0 =31.09（ mm）2.各層材料容許層底拉應(yīng)力：Rsp / Ks1）細(xì)粒式密級(jí)配瀝青混凝土：Ks 0.09 Aa Ne0.22 / Ac = 0.091.04312242 0.22 /1.1 =2.3

6、6R sp / K s =1.4/2.36=0.593MPa2）中粒式密級(jí)配瀝青混凝土：Ks0.09 Aa Ne0.22 / Ac = 0.091.04312242 0.22 /1.1 =2.36R sp / K s =1.0/2.36=0.432MPa3）粗粒式密級(jí)配瀝青混凝土：Ks0.09 Aa Ne0.22 / Ac = 0.091.14312242 0.22 /1.1 =2.59R sp / K s =0.8/2.59=0.309 MPa4）二灰碎石：K s0.35 N e0.11 / Ac = 0.354312242 0.11 /1.1 =1.7R sp / K s =0.5/1.7

7、=0.292 MPa5）石灰土：K s0.45 N e0.11 / Ac = 0.454312242 0.11 /1.1 =2.20R sp / K s =0.225/2.20=0.102 MPa六、設(shè)計(jì)資料總結(jié)設(shè)計(jì)彎沉值為 31.09（0.01mm），相關(guān)資料匯總?cè)缦卤聿牧厦Q細(xì)粒式密級(jí)配瀝青混凝土中粒式密級(jí)配瀝青混凝土粗粒式密級(jí)配瀝青混凝土二灰碎石石灰土土基七、確定石灰土層厚度細(xì)粒式瀝青混凝土中粒式瀝青混凝土粗粒式瀝青混凝土二灰碎石二灰土抗壓模量 E1(MPa)H容許拉應(yīng)力（ cm）（MPa）20153140020000.5935120018000.4327100014000.309201

8、5000.2925500.10230AprE1=1400MPaE2=1200MPaAE3=1000MPaE 4=1500MPaE5=550MPaE0=30MPa路表彎沉值計(jì)算圖式Ap1E1=1400MPah 3cmh2 5cmE2=1200MPa3E3 =1000MPah 7cmh420cmE 4=1500MPah5？ cmE5=550MPaE0=30MPa計(jì)算彎沉綜合系數(shù)：多層體系換算圖式Ls）0.38E0)0.36=1.6331.09)0.3828)0.36=0.514F=1.63（(2000P2000 10.650.7E030E20.031000h30.28210.65E21000E10

9、.7141400查三層體系表面彎沉系數(shù)諾謨圖得k1f ( h , E0 )f (0.282,0.03)1.448E2af ( h , E2 )f (0.282,0.714)7.68E1由 Ld 1000 2 pac FE1ac = ak1k2 得k2 =0.511查三層體系表面彎沉系數(shù)諾謨圖得H5.22H=55.59cmh h1 3cmE1 1400MPaH？E2 1200MPaE0 30MPan 1E4E5=55.59HhK 2.4h2h3 h4h52.4得K 2E2E2h532.65 cm 取 h535 cm八、層底拉應(yīng)力驗(yàn)算（采用15瀝青的抗壓模量）細(xì)粒式密級(jí)配瀝青混凝土為2000MPa

10、，中粒式密級(jí)配瀝青混凝土為1800MPa，粗粒式密級(jí)配瀝青混凝土為 1400MPa1.對(duì)于細(xì)粒式瀝青混凝土層：n 1E4E3E4E5Hhk 0.9h2 h3 0.9h40.9+ h5 0.9=36.00Ei 1E2E2E2K i 1H 36.00 =3.38110.65h3=0.28210.65E030E20.0171800E21800E10.92000查三層連續(xù)體系上層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）hE2f (,) = f (0.282,0.9) 0P m1 m2 0R查三層連續(xù)體系中層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）n1= f ( E2, H )f (0.9,3.38

11、1) 1.234E1hh1 3cm1= f ( H , h , E2 ) f (3.381,0.282,0.9) =0.31E 2000MPan2E1H？2E 1800MPaf ( H , E0 )f (3.381,0.017) =0.341E0 30MPaE2P n1n2 =0.7×0.341×1.234× 0.31=0.0910.5932. 對(duì)于中粒式瀝青混凝土層：iEk=E14 18004h1hkEih14h23140058.19k 1E2n1EkE3E4E57200.9 1500350.9 550Hhk0.9h3 0.9h40.9h5 0.9=40.99K

12、 i 1Ei 1E3E3E314001400H3.85h0.769h ?E11800MPaE030H？20.02E 1400MPaE21400E0 30MPaE214000.778E11800查三層連續(xù)體系上層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）hE2f (,) = f (0.769,0.778) 0P m1m2 0R查三層連續(xù)體系中層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）n1 = f ( E2, H ) f (0.778,3.85) =1.166E1n2 = f ( H , h , E2 )f (3.85,0.769,0.778) =0.25E1f ( H , E0 )f (3.8

13、5,0.02) =0.26E2P n1n2 =0.053 0.4323.對(duì)于粗粒式瀝青混凝土層iEkE1E23 4 20006 4 1800hhk 4h1 4h2 4h37 16.67K 1EiE3E314001400n 1EkE520 350.9 550 =31.48Hhk 0.9h4h5 0.9K i 1Ei 1E41500H2.96h ?E11400MPah1.57H？2E 1500MPaE0300.02E0 30MPaE21500E215001.07E11400查三層連續(xù)體系上層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）f ( h , E2 ) = f (1.57,1.07) 0 E1

14、P m1 m2 0R查三層連續(xù)體系中層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）n1= f ( E2, H ) f (1.07,2.96) =1.23E1n2 = f ( H , h , E2 )f (2.96,1.57,1.07) =0.46E1f ( H , E0 )f (2.96,0.02) =0.46E2P n1n2 =0.182 0.3094. 對(duì)二灰碎石iEkE1E2E3200018001400hhkh1h2h3h436 4444447 420 36.38K 1EiE4E4E4150015001500n1Ek =35Hh 0.9k i 1kEi 1H3.29hE030E215003

15、.425500.052.73E2E1550查三層連續(xù)體系上層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）hE2) = f (3.42,2.73) 0h ?1f ( ,E1E 1500MPaH？2P m1m2 0E 550MPaE0 30MPaR查三層連續(xù)體系中層底面彎拉應(yīng)力系數(shù)諾謨圖（上層中層層間連續(xù)）n1= f ( E2, H )f (2.73,3.29) =1.31E1n2 = f ( H, h , E2 ) f (3.29,3.42, 2.73) =0.53E1f ( H , E0 )f (3.29,0.05) =0.25E2P n1n2 =0.174 0.292綜上所述，各層均滿足要求九、進(jìn)行防凍層厚度驗(yàn)算該路段路面結(jié)構(gòu)總厚度為H3+5+7+20+35 70cm。道路