惠家廟公路隧道結(jié)構(gòu)計算.docx

此文檔收集于網(wǎng)絡(luò)，如有侵權(quán)，請聯(lián)系網(wǎng)站刪除一基本資料 惠家廟公路隧道，結(jié)構(gòu)斷面尺寸如下圖，內(nèi)輪廓半徑為6.12m，二襯厚度為 0.45m。圍巖為 V 級，重度為19.2kN/m3，圍巖彈性抗力系數(shù)為 1.6105kN/m3，二襯材料為 C25 混凝土，彈性模量為 28.5GPa，重度為 23kN/m3?？紤]到初支和二襯分別承擔(dān)部分荷載，二襯作為安全儲備，對其圍巖壓力進(jìn)行折減，對本隧道按照 60%進(jìn)行折減。求二襯內(nèi)力，作出內(nèi)力圖，偏心距分布圖。1）V1級圍巖，二襯為素混凝土，做出安全系數(shù)分布圖，對二襯安全性進(jìn)行驗(yàn)算。2）V2級圍巖，二襯為鋼筋混凝土，混凝土保護(hù)層厚度 0.035m，按結(jié)構(gòu)設(shè)計原理對其進(jìn)行配筋設(shè)計。二荷載確定1.圍巖豎向均布壓力:q=0.60.45式中: S圍巖級別，此處S=5；-圍巖重度，此處=19.2KN/；-跨度影響系數(shù)，=1+i（-5），毛洞跨度=13.14+20.06=13.26m，其中0.06m為一側(cè)平均超挖量，=515m時，i=0.1,此處=1+0.1(13.26-5)=1.826。所以，有：q=0.60.4519.21.826=151.456（kPa）此處超挖回填層重忽略不計。2.圍巖水平均布壓力：e=0.4q=0.4151.456=60.582（kPa）三襯砌幾何要素5.3.1襯砌幾何尺寸內(nèi)輪廓線半徑內(nèi)徑所畫圓曲線的終點(diǎn)截面與豎直軸的夾角；拱頂截面厚度墻底截面厚度此處墻底截面為自內(nèi)輪廓半徑的圓心向內(nèi)輪廓墻底做連線并延長至與外輪廓相交，其交點(diǎn)到內(nèi)輪廓墻底間的連線。外輪廓線半徑：拱軸線半徑：拱軸線各段圓弧中心角：5.3.2半拱軸線長度S及分段軸長分段軸線長度：半拱線長度：將半拱軸線等分為8段，每段軸長為：5.3.3各分塊接縫（截面）中心幾何要素（1）與豎直軸夾角另一方面，角度閉合差0。（注：因墻底面水平，計算襯砌內(nèi)力時用）四計算位移1.單位位移用辛普生法近似計算，按計算列表進(jìn)行。單位位移的計算見附表。單位位移值計算如下：計算精度校核為：閉合差。單位位移計算表見下：單位位移計算表精品文檔單位位移計算表截面sincosxydI1/Iy/Iy2/I(1+y)2/I積分系數(shù)1/3000.0000 1.0000 0.0000 0.0000 0.4500 0.0076 131.6872 0.0000 0.0000 131.6872 1112.8177 0.2219 0.9751 1.4076 0.1581 0.4500 0.0076 131.6872 20.8214 3.2921 176.6222 4225.6355 0.4326 0.9016 2.7451 0.6246 0.4500 0.0076 131.6872 82.2480 51.3696 347.5528 2338.4532 0.6219 0.7831 3.9458 1.3761 0.4500 0.0076 131.6872 181.2182 249.3791 743.5027 4451.2709 0.7801 0.6256 4.9498 2.3753 0.4500 0.0076 131.6872 312.7997 743.0001 1500.2866 2564.0886 0.8995 0.4370 5.7071 3.5724 0.4500 0.0076 131.6872 470.4345 1680.5622 2753.1184 4676.9064 0.9740 0.2265 6.1800 4.9076 0.4500 0.0076 131.6872 646.2664 3171.6074 4595.8274 2789.7241 1.0000 0.0048 6.3449 6.3144 0.4500 0.0076 131.6872 831.5322 5250.6662 7045.4178 48901.0000 0.0000 6.3450 6.3450 0.4500 0.0076 131.6872 835.5556 5301.6000 7104.3984 11053.4979 2978.0696 13989.7175 20999.3546 2.載位移主動荷載在基本結(jié)構(gòu)中引起的位移 (1)每一楔塊上的作用力豎向力：式中：水平壓力：式中：襯砌外緣相鄰兩截面之間的豎直投影長度自重力：式中：接縫i的襯砌截面厚度。（2）外荷載在基本結(jié)構(gòu)中產(chǎn)生的內(nèi)力楔塊上各集中力對下一接縫的力臂由圖5-2中量得，分別記為。計算附表見下載位移Mpo計算表截面集中力力臂-Qaq-Gag-Eaei-1(Q+G)i-1EXY-Yi-1(Q+G)-Yi-1EMp0QGEaqagae000000000000000001220.75614.6919.9180.67890.70360.3013-149.863-10.336-2.988001.40760.158100-163.1872209.75314.69129.2610.59510.65920.4444-124.827-9.684-13.002235.4479.9181.33750.4665-314.907-4.627-630.2333188.29814.69147.1450.48170.58490.5653-90.703-8.593-26.651459.89239.1791.20070.7516-552.179-29.446-1337.8064157.45714.69162.6800.34430.48150.6581-54.210-7.074-41.249662.88186.3251.00400.9992-665.545-86.255-2192.1395118.76914.69175.0910.18970.35410.7181-22.532-5.202-53.920835.029149.0050.75731.1970-632.391-178.364-3084.548674.16214.69183.7590.02570.20900.7423-1.905-3.071-62.171968.490224.0950.47291.3352-457.992-299.217-3908.904725.85914.69188.253-0.13960.05360.72953.611-0.787-64.3771057.343307.8540.16491.4069-174.344-433.109-4577.90980.01214.69188.670-0.3338-0.07520.68300.0041.105-60.5631097.894396.107-0.10871.4137119.395-559.996-5077.96455內(nèi)力按下式計算（見圖5-3）。彎矩：圖5-3 內(nèi)力計算圖示軸力：式中：-相鄰兩接縫中心點(diǎn)的坐標(biāo)增值，按下式計算：的計算見上表及下表。載位移Npo計算表截面sincos（Q+G）Esin(Q+G)cosENpo00.00001.00000.00000.00000.00000.00000.000010.22190.9751235.44699.918552.23409.671342.562720.43260.9016459.891739.1795198.969335.3229163.646430.62190.7831662.880686.3248412.228967.6024344.626540.78010.6256835.0290149.0047651.417093.2231558.193950.89950.4370968.4897224.0953871.128697.9252773.203460.97400.22651057.3432307.85431029.853669.7422960.111471.00000.00481097.8881396.10721097.87541.90731095.968081.00000.00001112.5794484.77761112.57940.00001112.5794基本結(jié)構(gòu)中，主動荷載產(chǎn)生彎矩的校核為：另一方面，從表3-2中得到閉合差（3）主動荷載位移計算精度校核閉合差D0。計算內(nèi)容詳見下表主動荷載位移計算表截面Mpo1/Iy/I(1+y)Mpo/IMpoy/IMpo(1+y)/I積分系數(shù)1/300.0000 131.6872 0.0000 1.0000 0.0000 0.0000 0.0000 11-163.1869 131.6872 20.8214 1.1581 -21489.6343 -3397.7826 -24887.4169 42-630.2332 131.6872 82.2480 1.6246 -82993.6713 -51835.3927 -134829.0640 23-1337.8059 131.6872 181.2182 2.3761 -176171.9650 -242434.7921 -418606.7571 44-2192.1391 131.6872 312.7997 3.3753 -288676.7533 -685700.3750 -974377.1282 25-3084.5483 131.6872 470.4345 4.5724 -406195.6670 -1451077.9017 -1857273.5687 46-3908.9036 131.6872 646.2664 5.9076 -514752.7411 -2526193.0093 -3040945.7505 27-4577.9093 131.6872 831.5322 7.3144 -602852.2560 -3806678.8812 -4409531.1372 48-5077.9646 131.6872 1017.7049 8.7282 -668703.1512 -5167869.4192 -5836572.5704 1-2422795.8573 -11236561.4679 -13659357.3252 5.4.3載位移單位彈性抗力及相應(yīng)的摩擦力引起的位移（1）各接縫處的抗力強(qiáng)度抗力上零點(diǎn)假定在接縫3，；最大抗力值假定在接縫5，最大抗力值以上各截面抗力強(qiáng)度按下式計算：查表算得：最大抗力值以下各截面抗力強(qiáng)度按下式計算：式中：-所考察截面外緣點(diǎn)到h點(diǎn)的垂直距離；-墻角外緣點(diǎn)到h點(diǎn)的垂直距離。由圖5-1中量得：則：按比例將所求得的抗力繪于圖5-2上。（2）各楔塊上抗力集中力按下式近似計算：式中：-楔快i外緣長度，可通過量取夾角，用弧長公式求得，的方向垂直于襯砌外緣，并通過楔塊上抗力圖形的形心。（3）抗力集中力與摩擦力的合力按下式計算：式中：-圍巖與襯砌間的摩擦系數(shù)，此處取=0.2。則：其作用方向與抗力集中力的夾角。由于摩擦阻力的方向與襯砌位移的方向相反，其方向向上。畫圖時，也可取切向：徑向=1：5的比例求出合力的方向。的作用即為與襯砌外緣的交點(diǎn)。將的方向線延長，使之交于豎直軸，量取夾角，將分解為水平與豎直兩個分力：以上計算列入下表彈性抗力及摩擦力計算表截面(i-1+i)/2S外RksinkcoskRHRV300000000040.525310.262651.469790.393747.37470.73580.67720.28970.266651.000000.762651.469791.143158.44880.85220.52330.97410.598260.844250.922121.469791.382270.28650.94140.33731.30120.466270.514730.679491.469791.018582.72040.99190.12671.01030.129180.000000.257361.469660.385792.70050.9989-0.04710.3853-0.0182（4）計算單位抗力及其相應(yīng)的摩擦力在基本結(jié)構(gòu)中產(chǎn)生的內(nèi)力彎矩：軸力：式中： -力至接縫中心點(diǎn)的力臂，由附圖量得。計算見下表。Mo計算表截面R4=0.3937hR5=1.1431hR6=1.3822hR7=1.0185hR8=0.3857hMor4i-R4r4ir5i-R5r5ir6i-R6r6ir7i-R7r7ir8i-R8r8i40.4698 -0.1849 -0.1849 51.8860 -0.7425 0.6616 -0.7563 -1.4988 63.2725 -1.2884 2.0780 -2.3753 0.7697 -1.0638 -4.7276 74.5601 -1.7953 3.4550 -3.9494 2.1855 -3.0208 0.8121 -0.8271 -9.5927 85.7114 -2.2486 4.7438 -5.4226 3.5682 -4.9320 2.2300 -2.2712 1.0058 -0.3879 -15.2624 No計算表截面sincosRVsinRVRHcosRHNO4 51.2709 0.7801 0.6256 0.2666 0.2080 0.2897 0.1812 0.0268 5 64.0886 0.8995 0.4370 0.8648 0.7778 1.2638 0.5523 0.2256 6 76.9064 0.9740 0.2265 1.3310 1.2964 2.5650 0.5811 0.7153 7 89.7241 1.0000 0.0048 1.4600 1.4600 3.5752 0.0172 1.4428 8 90.0000 1.0000 0.0000 1.4419 1.4419 3.9605 0.0000 1.4419 (5)單位抗力及相應(yīng)摩擦力產(chǎn)生的載位移計算見下表。單位抗力及摩擦力產(chǎn)生的載位移計算表截面M1/Iy/I(1+y)M/IMy/IM(1+y)/I積分系數(shù)1/34-0.1849131.6872312.79973.3753-24.3553-57.8517-82.207025-1.4988131.6872470.43454.5724-197.3728-705.0870-902.459846-4.7276131.6872646.26645.9076-622.5603-3055.2676-3677.827927-9.5927131.6872831.53227.3144-1263.2300-7976.5995-9239.829548-15.2624131.68721017.70498.7282-2009.8581-15532.5782-17542.43631-3048.7001-18828.5210-21877.2211校核為：閉合差。5.4.4墻底（彈性地基上的剛性梁）位移單位彎矩作用下的轉(zhuǎn)角：主動荷載作用下的轉(zhuǎn)角：單位抗力及相應(yīng)摩擦力作用下的轉(zhuǎn)角：5.5 解力法方程襯砌矢高計算力法方程的系數(shù)為：以上將單位抗力及相應(yīng)摩擦力產(chǎn)生的位移乘以，即為被動荷載的載位移。求解方程為：其中：其中：以上解得的值應(yīng)代入原方程，校核計算是否正確，此處從略。5.6 計算主動荷載和被動荷載分別產(chǎn)生的襯砌內(nèi)力計算公式為：計算過程列入下表。主、被動荷載作用下襯砌彎矩計算表截面MpoX1pX2p*yMpM0X1X2*yM00.000471.6070.000471.6070-2.98120.0000-2.98121-163.187471.60793.501401.9200-2.98120.3617-2.61942-630.233471.607369.343210.7170-2.98121.4289-1.55223-1337.806471.607813.780-52.4190-2.98123.14840.16734-2192.139471.6071404.661-315.872-0.1849-2.98125.43452.26835-3084.548471.6072112.537-500.405-1.4988-2.98128.17313.69326-3908.904471.6072902.129-535.168-4.7276-2.981211.22803.51927-4577.909471.6073734.085-372.218-9.5927-2.981214.44671.87298-5167.089471.6074703.1697.687-15.2624-2.981218.1960-0.0475主、被動荷載作用下襯砌軸力計算表截面NpoX2p*cosNpNoX2*cosN00.000591.356591.3560.00002.28792.2879142.563576.620619.1820.00002.23092.23092163.646533.146696.7920.00002.06272.06273344.627463.100807.7270.00001.79171.79174558.194369.975928.1690.02681.43141.45815773.203258.4111031.6140.22560.99981.22536960.111133.9671094.0790.71530.51831.233671095.9732.8481098.8211.44280.01101.453881112.5850.0001112.5851.44190.00001.44195.7 最大抗力值的求解首先求出最大抗力方向內(nèi)的位移?？紤]到接縫5的徑向位移與水平方向有一定得偏離，因此修正后有：計算過程列入下表，位移值為：最大抗力值為：最大抗力位移修正計算表截面Mp/IM/I力臂Mpl力臂/IMl力臂/I積分系數(shù)1/3062104.57106-392.581225.7071354439.786-2240.517911152927.8021-344.94425894.9498261982.913-1707.410824227748.70632-204.40753033.9458109490.765-806.5506423-6902.95075422.024826622.7451-18949.46260.4608999844-41596.28643298.71245891.4076-58552.588420.47954625-65896.93759486.34495960.0000004476149.982-3200.153265.8 計算襯砌總內(nèi)力按下式計算襯砌總內(nèi)力：計算過程列入下表。襯砌總內(nèi)力計算表截面MpMMNpNNeM/IMy/I積分系數(shù)1/30471.607 -424.097 47.510 591.356 325.47