#預(yù)應(yīng)力混凝土簡(jiǎn)支梁橋計(jì)算二11B

1、b:計(jì)算抗扭修正系數(shù)：本設(shè)計(jì)主梁的間距相同，同時(shí)將主梁近似看成等截面，則得：一：EI(B)It計(jì)算表表1-4分塊名稱bi(cm)ti(cm)ti/biCiTti=cibiti3_34(X10m)翼緣板O1160180.11250.30932.88614腹板C2149.5200.13380.30493.64660馬蹄O35032.50.650.20903.7589310.29167注：系數(shù)Ci是根據(jù)t/b值由姚玲森主編的橋梁工程表252查得。式中：G=0.43EL=34.00m,l=0.37947313m4,為與主梁片數(shù)n有關(guān)的系數(shù),當(dāng)n=5時(shí)，=1.042；B=8.5mG=0.43E;-=0.

2、8372；c:按修正的剛性橫梁法計(jì)算橫向影響線豎坐標(biāo)值：0=1半n丁2Zaii=1N=5,a1=3.2m，a2=1.6m，a3=0ma4=-16m，a5=-32m；52222則ai=2X(3.2+1.6)=25.6m;計(jì)算所得的j值列表于15中：i=1ij值表1-5梁號(hào)e(mni1i4嘰ni2ni313.20.53490.0326-0.13410.36740.221.60.36740.11630.032560.28370.2300.20.20.20.20.2d:計(jì)算荷載橫向分布系數(shù)：1,2,3號(hào)梁的橫向影響線和最不利布載圖示如圖16,對(duì)1號(hào)梁，貝汽一20：mq=1/2'1j=1/2()

3、=0.5197;掛一100：皿=1/2、1j=1/4(0.4720+0.3741+0.2762+0.1782)=0.3251;人群荷載：mcr=0.6216;(2) :支點(diǎn)的荷載橫向分布系數(shù)m如圖(1-7)所示，按杠桿原理法繪制荷載橫向影響線并進(jìn)行布載，1號(hào)梁活載的橫向分布系數(shù)可按計(jì)算如下：I爲(wèi)1_人群人群mniiiij號(hào)梁號(hào)梁號(hào)梁汽-201寸Tv'-官-L11'LSXldZ11111圖16跨中的橫向分布系數(shù)mi計(jì)算圖示汽20:皿=0.5X0.8750=0.4375;掛一100:皿=0.25X0.5625=0.1406;人群荷載：mor=1.4219;人群1號(hào)梁2號(hào)梁汽-20掛

4、/4汽-20掛-100I+二-hfFCJ圖17支點(diǎn)的橫向分布系數(shù)mo計(jì)算圖示(尺寸單位：m)(3) :橫向分布系數(shù)匯總：表16；1號(hào)梁活荷載橫向分布系數(shù)表16何載類別mimo汽一200.51970.4375掛一1000.32510.1406人群0.62161.42193:計(jì)算活荷載內(nèi)力:在活載內(nèi)力計(jì)算中，本設(shè)計(jì)對(duì)于橫向分布系數(shù)的取值作如下考慮；計(jì)算主梁活載彎距時(shí)，均采用全跨統(tǒng)一的橫向分布系數(shù)mc，鑒于跨中和四分點(diǎn)剪力影響線的較大坐標(biāo)位于橋跨中部，見圖18，故也按不變的me來計(jì)算。求支點(diǎn)和變化點(diǎn)截面活載剪力時(shí)，由于主要荷載集中在支點(diǎn)附近而應(yīng)考慮支承條件的影響，按橫向分布系數(shù)沿橋跨的變化曲線取值，

5、即以支點(diǎn)到L/4之間，橫向分布系數(shù)用mo與mc值直線插入，其余區(qū)段取mc值。（見圖19和圖1-10）_,_掛-100411in_,_掛-100411in9mm'LMrr剪力影響線汽-20掛-100彎距影響線一圖18跨中截面內(nèi)力計(jì)算圖式（尺寸單位：cm）（1）：計(jì)算跨中截面最大彎距和最大剪力采用直接加載求活載內(nèi)力，圖18式出跨中截面內(nèi)力計(jì)算圖式，計(jì)算公式為：S=（1+卩）©mc£Ryi式中：S所求截面的彎距或剪力；J-車輛沖擊系數(shù)；-車道折減系數(shù)；mc主梁荷載橫向分布系數(shù)；Pi車輛荷載的軸重；yi沿橋跨縱向與荷載位置對(duì)應(yīng)的內(nèi)力影響線坐標(biāo)值；a：對(duì)于汽車、掛車荷載內(nèi)力，

6、列表計(jì)算在表17內(nèi);表17荷載類型汽-20掛-1001+卩1.08251.0最大彎距Pi1307012012060250250250250yi1.53.58.57.85.88.57.95.95.3mc0.51970.3251Mmax=（1+卩）-ni送Ryi2243.19最大剪力P12012060250250250250yi0.50.45880.34120.50.46470.34710.3118m0.51970.3251Qmax=(1+卩)£m送Pyi131.96b:對(duì)于人群荷載：q=0.75X3=2.25Kn/mMmax=1/8ml2=0.125X0.6216X2.25X342相應(yīng)

7、：Q=QQmax=1/8mql=0.125X0.6216X2.25X34=5.944Kn相應(yīng)M=1/16X0.6216X2.25X342=101.049Kn.m（2）:求四分點(diǎn)截面的最大彎距和最大剪力（按等代荷載計(jì)算）計(jì)算公式：S=（1+）mck'1式中門為內(nèi)力影響線面積，如圖14所示，對(duì)于四分點(diǎn)彎距影響線面積為3L2/32=108.375m2，剪力影響線面積為9L/32=9.563m2，于是：Mmax=108.375（1+）mck；Qmax=9.563（1+）mck1號(hào)梁的內(nèi)力列表計(jì)算見表18：1號(hào)梁梁四分點(diǎn)截面內(nèi)力計(jì)算表表18荷載類型項(xiàng)目1+4K(Kn/m)Qmc內(nèi)力值Mmax1.

8、082519.236108.3751172.802（Kn/m）0.5197汽一20Qmax(Kn)23.2049.563124.835Mmax1.045.838108.3751614.997（Kn/m）0.3251掛一100Qmax(Kn)61.0759.563189.880Mmax1.0108.375151.573（Kn/m）2.250.6216人群Qmax(Kn)9.56313.375（3）:求變化點(diǎn)截面的最大彎距和最大剪力：圖19示出變化點(diǎn)截面內(nèi)力的計(jì)算圖式，內(nèi)力計(jì)算見表19：1號(hào)梁變化點(diǎn)截面內(nèi)力計(jì)算表表1-9十卜Ll-t汽-20掛-100人群荷載內(nèi)力1+1.08251.01.0最m0.

9、5197032510.6216大P6401000q=2.25彎0.96931.4792Qn=34X1.9509/2距yMmax=(1+»)mPy=348.995KN/m480.88853.043Pi60120120701307250250250250Q=2.250最yi0.940.830.790.560.4400.810.780.660.620.50.88911503032668153885X26大0.9491剪m0.450.480.500.51970.260.280.32510.620.5498706517916XX力32.20.63707X6.77Qmax=(1+卩)工Piyim

10、i=186.653KN215.41425.658(4) :求支點(diǎn)截面的最大剪力：圖110示出支點(diǎn)最大剪力計(jì)算圖式，最大剪力列表計(jì)算在表110內(nèi);1號(hào)梁支點(diǎn)最大剪力計(jì)算表表1-10荷汽-20掛-100r人群載1+1.08251.01.0$Pi6012012070130713250250250250Q=2.2500yi1.00.880.840.540.42000.800.770.650.610.50.91241271945906297767m0.430.470.480.51970.160.220.32510.620.5751332515116XX34.00.80003X8.5Qmax=(1+4)1

11、Piyimi=144.834KN179.89730.792一人48no0240S07.noCK50O-IrTDo095.20n-3剪力影響線掛-100vu-o29ca9圖110支點(diǎn)剪力（1號(hào)梁）計(jì)算圖式（尺寸單位：m）掛-100人群汽-20彎距影響線剪力影響線LOTTo20圖19變化點(diǎn)截面內(nèi)力（1號(hào)梁）計(jì)算圖式（尺寸單位：m）123主梁內(nèi)力組合本設(shè)計(jì)按“橋規(guī)”第條規(guī)定，根據(jù)可能同時(shí)出現(xiàn)的作用荷載選擇了荷載組合和川,在表111中先匯總前面計(jì)算所得的內(nèi)力值，然后根據(jù)公預(yù)規(guī)第條規(guī)定進(jìn)行內(nèi)力組合及提高荷載系數(shù)，最后用粗線框出控制設(shè)計(jì)的計(jì)算內(nèi)力；內(nèi)力組合表表一11序何載類別跨中截面四分點(diǎn)截面變化點(diǎn)截面支

12、點(diǎn)MmaxQmaxMmaxQmaxMmaxQmaxQmax號(hào)(KN/m(KN)(KN/m)(KN)(KN/m)(KN)(KN)1一期橫載:3081.02904621.54181.2375799.61319.83362.472二期橫載757.180567.88544.54167.6778.6089.083總=1+23838.4705189.43225.785967.28398.43451.554人群202.0985.944151.57313.37553.04325.65830.7925汽一201543.7176.251172.802124.835348.995186.653144.8346掛一1

13、002243.19131.961614.997189.88480.888215.414179.8977汽+人=1+51745.8182.191324.38138.21402.04212.31175.638恒+汽+人=3+75584.2882.196512.81363.996369.32610.74627.189恒+掛=3+66081.66131.966804.43415.666448.17613.84631.4510S1=1.2X恒+1.4X(汽+人)7050.30115.072561.45464.437723.60775.35787.7411S"=1.2X恒+1.1X掛7073.6

14、7145.168003.81479.807689.70715.07739.7512汽/(8)X100%28%93%18%34%5%31%23%13掛/(9)X100%37%100%24%46%7%35%28%14提高后的S17050.30115.072561.45464.438109.78798.61811.3715提高后的Sm7427.35149.528404.00494.197689.70715.07739.751.3 預(yù)應(yīng)力鋼束的估算及其布置1:按使用階段的應(yīng)力要求估算鋼束數(shù)：n二GAAyRy(ks0)式中：M使用荷載產(chǎn)生的跨中彎矩，按表10取用；Ci與荷載有關(guān)的經(jīng)驗(yàn)系數(shù)，對(duì)于汽-20,

15、G=0.51;對(duì)于掛-100，取Ci=0.565;Ay一根32©s5的鋼束截面積，即：Ay=8.4cm2；在第一節(jié)中已計(jì)算出成橋后跨中截面yx=119.284cm;ks=42.650cm；初估ay=15cm則鋼束偏心距為：ey=yx-ay=104.284cm；：對(duì)(恒+汽+人)荷載組合：5584.28如03n464.80.518.410*1860106(0.42651.0428)(1) ；對(duì)(恒+掛)荷載組合：n嚴(yán)譽(yù)34.7101860106(0.42651.0428):按承載能力極限狀態(tài)估算鋼束數(shù):MjnahAAyRy式中：Mj承載能力極限狀態(tài)的跨中最大彎距，按表111取用;a-經(jīng)

16、驗(yàn)系數(shù)，一般取用0.750.77，本設(shè)計(jì)取0.76；Ry預(yù)應(yīng)力鋼鉸線的設(shè)計(jì)強(qiáng)度，見表11,為1488MPa3=4.48404.00X00.768.410*14881062根據(jù)上述兩種極限狀態(tài)，取鋼束數(shù)n=7；預(yù)應(yīng)力鋼束布置1:跨中截面及錨固端截面的鋼束布置：(1) 對(duì)于跨中截面，在保證布置預(yù)留管道構(gòu)造要求的前提下，盡可能使用鋼束群重心到截面形心的偏心距大些。本設(shè)計(jì)采用內(nèi)徑70mm外徑77mm勺預(yù)埋鐵皮波紋管，根據(jù)“公預(yù)規(guī)”，管道水平凈距不應(yīng)小于4cm至梁底凈距不應(yīng)小于5cm,至梁側(cè)凈距不應(yīng)小于3.5cm，跨中截面的細(xì)部構(gòu)造如圖111a所示，由此可直接得出鋼束群重心至梁底距離為：3匯(9.0+1

17、6.7)+28.4ay=15.07cma)跨中截面(2) :由于主梁預(yù)制時(shí)為小截面，若鋼束全部在預(yù)制時(shí)張拉完畢，有可能會(huì)在上緣出現(xiàn)較大的拉應(yīng)力?？紤]到這個(gè)原因，本設(shè)計(jì)預(yù)制時(shí)在梁端錨固N(yùn)1N6號(hào)鋼束，N7號(hào)鋼束在成橋后錨固在兩梁頂，布置如圖111C;對(duì)于錨固端截面，鋼束布置通?？紤]下述兩方面：一：預(yù)應(yīng)力鋼束合力重心盡可能靠近截面形心，使截面均勻受壓；二：考慮錨頭布置的可能性，以滿足張拉操作方便的要求；按照上述錨頭布置的“均勻”、“分散”原則，錨固端截面的鋼束布置如圖111b)所示。鋼束群重心至梁底距離為：ay240801251556=86.67cm1圖111b)錨固截面為驗(yàn)證上述布置的鋼束群重心

18、位置，需計(jì)算錨固端截面幾何特性。圖112示出計(jì)算圖示計(jì)算圖式，錨固端截面特性見表112所示。J二J./I48U二（二圖111c)N7號(hào)鋼束艮縱向布置 32ys=三Si/2Ai=1018144cm/11944cm=85.24cm32ys=三Si/2Ai=1018480cm/11980cm=85.01cmyx=h-ys=114.76cm故計(jì)算得；Ks=三1/2Ayx=46781334.56/1194!X114.76=34.13cmKx=31/2Ays=46781334.56/1194!X85.24=45.85cm；y=ay-Ks-Kx=86.67-（）=6.04cm；說明鋼束群重心處在截面核心范圍

19、內(nèi)。2:鋼束彎起角和線形的確定：確定鋼束彎起角時(shí)，既要照顧到由其彎起產(chǎn)生足夠的豎向預(yù)剪力，又要考慮到所引起的預(yù)應(yīng)力摩擦損失不宜過大，為此本設(shè)計(jì)將錨固端截面分成上、下兩部分（見圖1-13），上部鋼束的彎起角為15度；下部鋼束彎起角為7度；在梁頂錨固的鋼束彎起角為18度；N7號(hào)鋼束在離支座中心線1500mn處錨固，如圖（111c）；錨固端截面特性表1-12分塊名稱AyiSIidi=ys-yiIx=Aidi2I=Ii+Ix(cmi)(cm)(cm5)(cm)(cm)(cm4)(cm)(1)(2)(3)=(1)+(2)(4)(5)(6)(7)=(4)+(6)翼板18966113762275279.24

20、11909448.7119322007三角承6481610368518469.243106627.093111811.09托腹板940010699640027686133.33-20.764051189.4431737322.771198010181444678133456112鋼束群重心位置復(fù)核圖式3:鋼束計(jì)算：(1) :計(jì)算鋼束彎起點(diǎn)至跨中的彎距：錨固點(diǎn)到支座中心線的水平距離axi(見圖1-13)為：ax1(ax2)=36-40xtg7°=31.09cm；ax3(ax4)=36-80xtg7°=26.18cm；ax5=36-15Xtg15°=31.98cm；a

21、x6=36-45xtg15°=23.94cm；ax7=-(150-36Xtg18°/2)=-144.44cm;圖114示出鋼束計(jì)算圖式，鋼束起彎起至跨中的距離x1列表計(jì)算在表113;佗0aa彎起結(jié)束點(diǎn)錨固點(diǎn)主梁底面線跨徑中線計(jì)算點(diǎn)圖114鋼束計(jì)算圖式（2）:控制截面的鋼束重心位置計(jì)算：:各束重心位置計(jì)算（見表114）:由圖114所示的幾何關(guān)系，當(dāng)計(jì)算截面在曲線段時(shí)，計(jì)算公式為:a=ao+R（1-cosa）sina=X4/R當(dāng)計(jì)算截面在近錨固點(diǎn)的直線段時(shí)，計(jì)算公式為：a=a°+y-X5tg式中；a-鋼束在計(jì)算截面處鋼束重心到梁底的距離；ao-鋼束彎起前到梁底的距離；

22、R-鋼束彎起半徑（見表1-13）表1-13彎起高度（cm）y1(cm)y2(cm)L1(cm)X3(cm)(o)R(cm)X2(cm)X1(cm)N(Nb)3112.1918.8110099.2574158.93506.851224.24Nj(Nk)63.312.1951.1110099.2578492.261034.95691.23N511625.8890.1210094.20153404.34881.11848.87N6138.325.88112.4210094.20154058.791050.49673.45N7156.630.90125.710093.18183199.61988.73

23、566.87：計(jì)算鋼束群重心到梁底距離ay（見表1-15）圖115繪出了表115的計(jì)算結(jié)果：截面鋼束X4（cm）R（cm）Sina=x4/Rcosaa。（cm）ai（cm）ay（cm）四分占八、Ni（N2）未彎起4158.939.09.017.42N3（N4）未彎起8492.2616.716.7N51.133404.340.00033190.9999999.09.0N6176.554058.790.04349820.99905416.720.54N7283.133199.610.08848890.99607728.44095變化占八、Ni（N2）345.764158.930.08313670.

24、9965389.023.4080.62N3（2）878.778492.260.10347890.99463216.762.29N5721.133404.340.21182670.9773079.086.26N6896.554058.790.22089100.97529916.7116.96N71003.163199.610.31352570.949579928.4189.73支占八、Ni（N2）314158.930.00745380.99997229.016.790.20N3（NO63.38492.260.00745380.999972216.779.8N51163404.340.034074

25、20.99941939.0109.5No138.34059.790.03407420.999419316.7139.2四分點(diǎn)截面變化點(diǎn)截面變化點(diǎn)截面支點(diǎn)截面圖115鋼束重心的計(jì)算位置圖（cm）（3）:鋼束長(zhǎng)度計(jì)算：一根鋼束的長(zhǎng)度為曲線長(zhǎng)度、直線長(zhǎng)度與兩端張拉的工作長(zhǎng)度（2X70cm）之和，其中鋼束的曲線長(zhǎng)度可按圓弧半徑與彎起角度進(jìn)行計(jì)算。通過每根鋼束長(zhǎng)度計(jì)算，就可得出一片主梁和一孔橋所需鋼束的總長(zhǎng)度，結(jié)實(shí)結(jié)果見表115;鋼束號(hào)R（cm）鋼束彎起角®曲線長(zhǎng)度S=兀半R/180（cm）直線長(zhǎng)度（cm）鋼束有效長(zhǎng)度2X（S+X1）鋼束預(yù)留長(zhǎng)度（cm）鋼束長(zhǎng)度（cm）1234567=5+6N

26、（N2）4158.937o507.8521224.243464.18470X23604.2(X2)Nj(N4)8492.26701036.999691.233456.4581403596.5(X2)N53404.34150890.802848.873479.3441403619.4N64058.791501062.050673.453471.0001403611.0N73199.611801004.678566.873143.0961403283.107z24914.9每孔橋（五片梁）的鋼束（245）計(jì)算長(zhǎng)度為:2491.49X5=1245.75m；計(jì)算主梁截面幾何特性：1.4.1 截面面積及

27、慣性矩計(jì)算計(jì)算公式：對(duì)于凈截面：截面積：A=A-n小截面慣性矩：lj=l-nA（yis-yi）2對(duì)于換算截面：截面積：Ao=A+n5廠1）nA取用主梁截面（b仁160cm）計(jì)算：ny=5.43;具體計(jì)算見表116：截面慣性矩：2Io=l+n(ny-1)niA(yis-yi各階段截面對(duì)形心軸的靜炬計(jì)算在預(yù)應(yīng)力混凝土梁在張拉階段和使用階段都要產(chǎn)生剪應(yīng)力，這兩個(gè)階段的剪應(yīng)力應(yīng)該疊加。在每一個(gè)階段中，凡是截面中和軸位置和面積突變處的剪應(yīng)力都需要計(jì)算。因此，對(duì)于每一個(gè)荷載作用階段，需要計(jì)算四個(gè)位置（共8種）的剪應(yīng)力,所以需要計(jì)算下面幾種情況的截面凈矩：a:aa線（圖1-15）以上（或以下）的面積對(duì)中性軸

28、凈距；b:bb線以上（或以下）的面積對(duì)中性軸（兩個(gè)）的凈距；c:凈軸（jj）以上（或以下）的面積對(duì)中性軸（兩個(gè)）的凈距；d:換軸（oo）以上（或以下）的面積對(duì)中性軸（兩個(gè)）的凈距；計(jì)算結(jié)果列表117；118內(nèi);圖i15靜距計(jì)算圖式（cm其他截面特性均可用同樣方法計(jì)算，下面將計(jì)算結(jié)果一并列表于特性分類截面、分塊名稱分塊面積A(cm)分塊面積重心至上緣距離y(cm)分塊面積對(duì)上緣靜距S(cni)全截面重心到上緣距離ys(cm)分塊面積自身慣性矩1i(cm)di=ys+yi(cm)241y=Adi(cm)1=戈1i/戈Iy(cm4)bi=158cm凈截面毛截面745980.71660206175.9

29、837947313.5-4.73616730334290055.5扣管道面積(nEA)-325.96184.3-60074略-108.32-3824561I7133.0454198737947313.5-3657258bi=160cm換算截面毛截面745980.71660206185.0137947313.516.634206383059843647.45混凝土接縫8X2=16464略93.35139428鋼束換算面積(ny-1)n工A260.48184.3266131略-86.9519693075.95I7735.4886825637947313.521896333.9559843647.4

30、5計(jì)算數(shù)據(jù)AA=?X7.72=46.566cm2,n=7根，ny=5.43注：*指凈截面重心軸；*指換截面重心;分塊名稱及序號(hào)bi=158cm,ys=85.24cmb1=160cm,ys=85.01cm靜距類別及符號(hào)分塊面積A（CR?）分塊面積重心至全截面重心距離yi（cm）對(duì)凈軸*凈距Si-j=Ayi凈距類別及符號(hào)A（cm）yi（cm）對(duì)凈軸*凈距翼板翼緣部分對(duì)凈軸*靜距Sa-j（cm5）165679.24131321.44翼緣部分對(duì)換軸*靜距Sa-o（cni）168079.01132736.8角承托82869.2457330.7284069.0157968.4肋部048073.243515

31、5.248073.0135044.8y223707.36225750下角0馬蹄部分對(duì)凈軸*靜距Sb-j（cm5）22584.7619071馬蹄部分對(duì)換軸*靜距Sb-o（cmi）22584.9919123馬蹄01250102.261278251250102.49128113肋部030082.262467830082.4924747管道和鋼束-325.9699.06-32290260.4899.2925863139284197846翼板0凈軸以上凈面積對(duì)凈軸靜矩Sj-j（cm5）165679.24131221.44凈軸以上凈面積對(duì)凈軸靜矩S-o（cmi）168079.011327368角承托082

32、869.2457330.7284069.0157968.4肋部01704.842.62726591704.840.8269589.95y261211260295.2翼板換軸以上凈面積對(duì)凈軸靜矩So-j(cm3)165679.24131221.44換軸以上換算面積對(duì)換軸靜矩So-o(cm3)168079.01132736.8角承托82869.2457330.7284069.0157968.4肋部01700.242.51722671700.242.5172275.5y260819.16210980.7名稱符號(hào)單位截面跨中四分點(diǎn)變化點(diǎn)凝土凈截面凈截面Ajcm7133.047133.048520.69

33、11980凈慣矩Ijcm434290055.534290055.53889393546781434凈軸到截面上緣距離yjscm75.9875.1887.9285.01凈軸到截面下緣距離yjxcm124.02124.98112.08114.99截面抵抗矩上緣wscm451303.70451303.70442378.70550305.07下緣wxcm276488.11296488.11347019.4140683046對(duì)凈軸靜距翼緣部分面積S-jcm223707223824304764273884凈軸以上面積S-jcm261211261478364768483798換軸以上面積S-j3cm2608

34、19261206364694483706馬蹄部分面積Sb-jcm1392841393362769040鋼束群重心到凈軸距離ecm99.0697.2333.7630.28混凝土換算截面換算面積Ao2cm7745.387745.389874.8013468換算慣矩I。cm59843647.455993752.406439460869834636換軸到截面上緣距離yoscm85.0185.1894.3490.28換軸到截面下緣距離yoxcm114.99114.82105.62109.72截面抵抗矩上緣WoS3cm703960.10703624.71682291773534下緣3cm520424.80

35、521988.79609682363481對(duì)換軸靜矩翼緣部分面積Sa-o3cm225750225368285368325368凈軸以上面積S-o3cm260295260018361768467818換軸以上面積So-o3cm210981210672380692470692馬蹄部分面積Sb-o3cm1978461975433976430鋼束群重心到凈軸距離e。cm99.2998.6640.1436.17鋼束群重心到截面aycm15.0717.4280.6290.20下緣距離鋼束預(yù)應(yīng)力損失計(jì)算預(yù)應(yīng)力鋼束與管道壁之間的摩擦損失（csi見表1-19）；按規(guī)范，計(jì)算公式為：j=k1-e"&qu

36、ot;）ck=0.75R；=0.75X1860=1395MPa四分點(diǎn)截面管道摩擦損失o's1計(jì)算表表119鋼束號(hào)0=©-axk0+kx1e訃)(O)(rad)(m)MPaNi(N2)70.12229.32140.03250.032044.64Ni(N2)70.12229.25310.03240.0319844.50N514.9120：0.26019.36830.05880.057179.65Ns12.50760.21829.26690.05070.049468.91Nz9.92320.17316.76340.03970.038954.27表中©見表113,其中有co

37、sa求反得;由錨具變形、鋼束回縮引起的損失（cs2,見表1-20）按規(guī)范，計(jì)算公式為：cs2計(jì)算表表1-20注：本設(shè)計(jì)未考慮反向摩阻損失。鋼束號(hào)N(N2)N(N4)NsN6N7L(mm(見表1-15)3604.23596.53619.43611.03283.1125s2=漢10l63.2663.40629963.1469.451(MPa1.5.3 混凝土彈性壓縮引起的損失（cs4見表21）計(jì)算公式為：cs4=nyXAchl_ZNyoEMyoeyics4=+AjIj1.5.4 由鋼束預(yù)應(yīng)力松弛引起的損失（cs5）按規(guī)范，對(duì)于作超張拉的鋼絲束由松弛引起的應(yīng)力損失的終極值,按下式計(jì)算：*5=0.04

38、5ck=0.045X1395=62.78MPa數(shù)據(jù)224Aj=7133.04cmAy=8.4cmlo=34290172cmyix=85.31cmny=5.43鋼束號(hào)錨固時(shí)預(yù)加縱向軸力Nyo=AAyty°cosaINyo(0.1KN)eyi=yjx-ai(cm)預(yù)加彎矩Myo=Nyoeyi(Nom)龍Myo計(jì)算應(yīng)力損失的鋼束號(hào)相應(yīng)鋼束凈軸距離eyj龍Th1(MpaTs4=ny戈Th1(Mpa錨固鋼束應(yīng)力Tyo=Tk-Ts1-Ts2-Ts4(MpaTyoAycosa(見表1-14)Nyo(0.1KN)yNyo/AjyMyo/ljXeyi合計(jì)1291.8110851.21.010851.2

39、10851.298.2910665651066565Na105.991.523.064.584.71N21266.6110639.521.010639.5221490.73r105.99:11276832194248N98.293.016.789.7920.491242.8810440.191.0一10440.1931930.9298.2910261663220414N105.994.489.2313.7144.22N1216.4810218.41.010218.442149.31r105.991083048430346298.295.9113.3019.2170.62N61173.92986

40、0.930.99990549851.63352000.9598.299683175271779Ns105.997.2915.1122.4089.03N51134.609530.640.9999999530.63267531.58P105.99101015262819311.5.5 混凝土收縮和徐變引起的損失（TS6）按規(guī)范，計(jì)算公式如下：n厲?。?#176;°,1）+EyE9,i）s6:110口式中：Ts6全部鋼束重心處的預(yù)應(yīng)力損失值；Th鋼束錨固時(shí)，在計(jì)算截面上全部鋼束重心處由預(yù)加應(yīng)力（扣除相應(yīng)階段的應(yīng)力損失）產(chǎn)生的混凝土法向應(yīng)力，并根據(jù)張拉受力情況，考慮主梁重力的影響；»

41、;_Ay+Ag+Ay+Ag卩一配筋率，AA為鋼束錨錨固時(shí)相應(yīng)的凈截面積A;pA=1+e/r2ea鋼束群重心到截面凈軸的距離ej;r截面回轉(zhuǎn)半徑r2=lj/Aj；（二）-加載齡期為T時(shí)的混凝土徐變系數(shù)終值；,）-自混凝土齡期T開始的收縮應(yīng)變終值；2Ah1.徐變系數(shù)（二廠）和收縮應(yīng)變系數(shù)（二，）的計(jì)算構(gòu)件理論厚度=v式中：A主梁混凝土截面面積；u與大氣接觸的截面周邊長(zhǎng)度。2Ahu=740.16，u=20.15cm,（：，）=2.2，；（：，）=0.23X10_3跨徑四分點(diǎn)截面Ts6計(jì)算表表1-224計(jì)算數(shù)據(jù)4Nyo=6153.158KNMyo=7733.730KNMy1=3478.84KNlj=3

42、4290172cm25Aj=7133.04cmea=ej=97.23cmEy=1.9X10MPany=5.43計(jì)算ThNyo/Aj(MPaMyo-Mgo/IjXej(MPath(MPa（1）(2)(3)=(1)+(2):8.62612.03920.665計(jì)算應(yīng)力損失n產(chǎn)泮（牟1）+Ey客仟口s6計(jì)算公式：仆0吧分子項(xiàng)分母項(xiàng)(4)nyTh®(°°E246.864r2=Ij/Aj4807.231(5)e/®43.7pA=1+eA2/r22.967(6)(4)+(5)290.5641+10APa0.824%11.149Ts6=290.564/1.149=252

43、.88MPa1.5.6 成橋后張拉N7號(hào)鋼束引起的混凝土彈性壓縮損失成橋后四分點(diǎn)（TS4,計(jì)算表表5234計(jì)算數(shù)據(jù)224Ao=9874.80cmAy=8.4cmlo=64394608cmyox=105.62cmny=5.43鋼束號(hào)錨固時(shí)預(yù)加縱向軸力Nyo=AAytyocosaeyi=yjx-ai(cm)預(yù)加彎矩Myo=Nyoeyi(Nom)計(jì)算應(yīng)力損失的鋼束號(hào)相應(yīng)鋼束凈軸距離eyj戈th1(Mpa=Ts4>nylTh1(Mpa)錨固鋼束應(yīng)力Tyo=Tk-Tsi-Ts2-Ts4-Ts5-(Ts6Mpa)tyoAycosa(見表1-14)Nyo(0.1KN)Ny7/AoMy7/loXeYvo

44、合計(jì)*N71271.2810678.750.99607710636.8664.6768788689.921.080.962.0411.08Nj966.738120.531.0：8120.5388.9272207896.621.081.032.11P11.46N2950.957987.981.07987.9896.6277175589.921.080.962.0411.08N,927.227788.651.07788.6588.92692567N96.121.081.032.1111.46N900.827566.891.0：7566.8996.62173111385.081.080.911.99P10.81N6858.267209.380.9990547202.5688.98612794N596.621.081.032.1111.46N5847.677120.430.9999997120.4296.62687975N7955.62