施工猫道计算书(改)

1、施工猫道计算书1. 概述 XX长江公路大桥主跨达1490米，是我国迄今跨度最大的悬索桥。为了加快施工进度和降低费用，该桥施工单位拟采用不设抗风缆的施工方案，施工期间猫道的安全性是决定该施工方案能否成立的关键。 为保证该桥施工猫道的安全及其合理性，受XX路桥集团委托，西南交通大学土木工程学院对该桥施工猫道进行了计算分析研究，内容包括猫道在不同施工阶段受风载、温度变化、施工机具、人群荷载等作用下的静力安全性。 本报告介绍施工猫道计算分析研究的内容及主要结果。2. 计算分析基本参数 2.1 猫道布置及结构参数根据XX路桥集团技术发展处所提拱的猫道设计资料，XX长江公路大桥施工猫道总体布置图如图1a图

2、1c所示，猫道线形取平行于主缆在空缆状态时的中心线；架设钢箱梁之前，将猫道悬挂于主缆之下，并放松猫道承重钢丝绳两端的锚头。考虑到XX长江公路大桥为国内最大跨度的悬索桥，为了保证猫道施工的安全性，XX路桥集团率先提出了采用含上、下承重绳的门架式猫道，同时采用了制振装置使猫道更加合理。根据最新设计资料，猫道矢高f=134.137m，猫道每延米重为133.17kgf/m（含下承重绳、扶手绳、底网、侧网、扶手立柱、猫道横梁、木踏板等）；上承重绳32.76 kgf/m；索股滚筒间距8m，单件重50kg，折算为分布荷载为12.5kgf/m；牵引索股折算的均布荷载为44.0kgf/m；猫道门架间距50m，单

3、件重950kgf/个；横向天桥重量为7000kgf/个。具体各分项值可见表1所示，计算中猫道承重绳的弹性模量取为E=1.15×105MPa。图1a 猫道总体图图1 b 猫道铺装大样图图1 c 猫道门架表1 猫道设计参数项目规格单位重(kg/m)单件重(kg)每延米重(kg/m)承重绳8388.1965.52扶手绳(1)2325.4910.98扶手绳(2)421.51.656.63底面网（粗）5(50×75)5.1320.5底面网（细）2(25×25)1.556.2侧面网5(50×100)4.629.24猫道横梁槽1010.05.37猫道横梁75×

4、;75×86.913.71木踏板50×50×15000.003扶手立柱75×75×86.915.01索股滚筒间距8m5012.5索股2244猫道门架间距50m95019.0横向通道350020.67对于有抗风缆的方案，中跨抗风缆为52钢丝绳，每边两条，边跨抗风缆为48钢丝绳，每边两条，抗风拉杆为32钢丝绳如附图1所示。 2.2 风速的计算 根据公路桥涵设计通用规范JTJ021-89中全国基本风压图，镇江及扬州地区的基本风压为600Pa，相应的桥址20m高度处100年一遇的10min平均年最大风速为。参考公路桥梁抗风设计指南关于不同高度处风速换算

5、的规定，该地区10m高度处100年一遇10min平均年最大风速（即基本风速）为。另外，根据XX桥的实测风速资料，场地不同高度处的风速如表2所示。表2 XX桥的实测风速资料高度(m)10203040506080100120风速（m/s）22.524.826.327.428.329.030.231.232显然，由XX桥的实测风速资料所得的10米高度处基本风速较按公路桥涵设计通用规范JTJ021-89中全国基本风压图推算的结果要小，当然取现场实测资料应更附事实际，因而本报告取实测资料进行计算。由表2资料统计分析得XX长江公路大桥桥位地表粗糙度类别为介于I、II类场之间的场地，该桥主跨桥面离开设计水位

6、的平均高度约为60m，据此可推算出该桥在成桥状态下在桥面高度处的设计基准风速为关于施工阶段的设计风速，可取重现期为10年，则 据参考文献1的规定，相应的阵风风速为阵风系数乘以设计基准风速，对于I、II类地区阵风系数取1.38，即有： 为了保证猫道在施工过程中的安全，其发生静力失稳的临界风速须高于其施工阶段设计风速对应的阵风风速。 由于猫道高度变化较大，在实际计算时应考虑风速沿高度的变化，如采用幂指数律风剖面，由表2推算，可得在猫道的高度范围(60米200米)，其幂指数为=0.14，则该桥猫道不同高度处的计算风速为： 式中: Z为设计水位以上高度，时主跨桥面处计算风速。 2.3 猫道的静力三分力

7、系数作用于猫道上的静力风荷载与猫道的静力三分力系数有关，因此，首先进行猫道静力三分力系数的测定试验。XX桥施工猫道的静力三分力试验已由西南交通大学风工程试验研究中心在XNJD-1风洞试验室完成，相关内容可参见文献5。本报告列出试验结果，以数据列表的形式给出静力三分力系数，见表3表3 猫道静力三分力系数数据攻角(°)CHCVCMCDCL-201.0186-0.1552-0.02821.1412-0.0454-180.9882-0.1356-0.02811.0850-0.0409-160.9944-0.1210-0.02741.0715-0.0373-140.9668-0.1045-0.

8、02731.0257-0.0339-120.9295-0.0862-0.02400.9713-0.0285-100.9228-0.0744-0.01890.9536-0.0271-80.8680-0.0613-0.01590.8892-0.0259-60.7905-0.0426-0.01400.8016-0.0185-40.7409-0.0223-0.01190.7445-0.0073-20.6671-0.0225-0.01150.6694-0.015800.6398-0.0174-0.01130.6398-0.017420.6523-0.0062-0.01130.6511-0.012840.

9、66580.0043-0.01080.6652-0.009060.71550.0272-0.01400.72140.005580.77490.0445-0.01300.78890.0130100.80550.0682-0.00880.83430.0268120.83220.0729-0.00800.86660.0214140.87210.1014-0.00440.93120.0375160.89050.1141-0.00750.96510.0389180.92020.1342-0.01831.01900.0456200.91970.1505-0.01381.04260.0506 2.4 风荷载

10、计算 静风作用下，采用有限元方法进行结构内力计算。对于猫道结构，按下列公式计算出作用于猫道上单位长度上的静风荷载：阻力升力力矩式中：r为空气密度（1.225kg/m3），V为计算高度处的阵风风速，H为猫道高度（取1.45m），B为猫道宽（取4.0m），CH、CV、CM分别为主梁的阻力系数、升力系数、力矩系数，由节段模型试验提供。 索塔，其静风荷载只考虑阻力，其单位长度阻力为： 阻力式中：H为塔宽，CH=2.0，V为计算高度处阵风风速。在计算索塔和猫道承受的风荷载时，风速应按风剖面变化考虑不同高度的影响。不同高度处的计算风速按2.2节的计算公式计算，计算可得各阶段各节点风荷载。 2.5 温度变化

11、及人群荷载 根据当地气温情况温度变化按降温25考虑，人群荷载折算为均布荷载为5kg/m。3. 猫道计算及结果根据XX路桥集团所提供的资料，施工猫道在架设过程中较为不利的状态为：a 猫道架设阶段，此时猫道承重绳、底网、侧网等已架设完毕，但门架及门架承重绳未完成。b. 牵引索股阶段，此时猫道全部架设完毕，滚筒上亦有索股。在两种状态下较为不利的荷载组合应为：组合一：猫道自重+温度变化+人群荷载组合二：猫道自重+风荷载根据上述两不同的荷载组合和不利状态，采用ANSYS程序对猫道进行建模及非线性分析计算，可得各状态的结构内力及位移。建模总体思路如下：采用有限元法对XX长江大桥施工猫道进行离散，建立有限元

12、计算模型，建模时考虑整个结构，即中跨、边跨及索塔等。对于索塔、横向通道等按梁单元进行离散，对于每条猫道结构，考虑到在设计风荷载等荷载作用下，结构是静力稳定的5，各承重绳仍处于受拉状态，本报告为了简化计算，采用等效梁单元来模拟每条猫道，等效梁的刚度由较为细化的模型计算而得，由于猫道结构主要为缆索结构，其受力变形形态具有很强的非线性特征，应力等效梁的模型应考虑几何非线性（此主要指大位移，杆件轴力）的影响。细化的模型如图2所示，细化模型将8根承重绳分别用索单元模拟，横梁用梁单元模拟。利用图2的模型，根据有限元刚度的定义，将模型下端固定，上端加一单位位移（线位移或角位移）即可得相应自由度的刚度。或者换

13、算成等效梁的截面几何特性。 图2 细化猫道模型示意 3.1猫道架设阶段 此时猫道计算模型（见图3）及节点坐标（见表4）如下：图3a 猫道架设阶段猫道计算模型图3b 猫道架设阶段猫道计算模型图3c 猫道架设阶段猫道计算模型表4-1 猫道架设阶段节点坐标(索塔)节点号x坐标(m)Y坐标(m)z坐标(m)节点号x坐标(m)y坐标(m)z坐标(m)1745.00 0.00 -20.67 17-745.00 0.00 -20.67 2745.00 0.00 20.67 18-745.00 0.00 20.67 3745.00 38.45 -20.01 19-745.00 38.45 -20.01 474

14、5.00 38.45 20.01 20-745.00 38.45 20.01 5745.00 72.30 -19.43 21-745.00 72.30 -19.43 6745.00 72.30 19.43 22-745.00 72.30 19.43 7745.00 105.30 -18.86 23-745.00 105.30 -18.86 8745.00 105.30 18.86 24-745.00 105.30 18.86 9745.00 138.30 -18.29 25-745.00 138.30 -18.29 10745.00 138.30 18.29 26-745.00 138.30

15、18.29 11745.00 166.44 -17.81 27-745.00 166.44 -17.81 12745.00 166.44 17.81 28-745.00 166.44 17.81 13745.00 194.58 -17.32 29-745.00 194.58 -17.32 14745.00 194.58 17.32 30-745.00 194.58 17.32 15745.00 204.58 -17.15 31-745.00 204.58 -17.15 16745.00 204.58 17.15 32-745.00 204.58 17.15 表4-2 猫道架设阶段节点坐标(猫道

16、)上游猫道下游猫道节点号x坐标(m)Y坐标(m)z坐标(m)节点号X坐标(m)y坐标(m)z坐标(m)33-1205.000 29.936 -17.150 294-1205.000 29.936 17.150 34-1195.490 32.499 -17.150 295-1195.490 32.499 17.150 35-1185.980 35.099 -17.150 296-1185.980 35.099 17.150 36-1176.500 37.738 -17.150 297-1176.500 37.738 17.150 37-1167.030 40.414 -17.150 298-11

17、67.030 40.414 17.150 38-1157.570 43.129 -17.150 299-1157.570 43.129 17.150 39-1148.130 45.881 -17.150 300-1148.130 45.881 17.150 40-1138.700 48.671 -17.150 301-1138.700 48.671 17.150 41-1129.290 51.500 -17.150 302-1129.290 51.500 17.150 42-1119.890 54.366 -17.150 303-1119.890 54.366 17.150 43-1110.5

18、00 57.271 -17.150 304-1110.500 57.271 17.150 44-1101.130 60.213 -17.150 305-1101.130 60.213 17.150 45-1091.780 63.193 -17.150 306-1091.780 63.193 17.150 46-1082.440 66.211 -17.150 307-1082.440 66.211 17.150 47-1073.110 69.268 -17.150 308-1073.110 69.268 17.150 48-1063.800 72.362 -17.150 309-1063.800

19、 72.362 17.150 49-1054.500 75.494 -17.150 310-1054.500 75.494 17.150 50-1045.220 78.664 -17.150 311-1045.220 78.664 17.150 51-1035.950 81.872 -17.150 312-1035.950 81.872 17.150 52-1026.700 85.118 -17.150 313-1026.700 85.118 17.150 53-1017.460 88.402 -17.150 314-1017.460 88.402 17.150 54-1008.230 91.

20、724 -17.150 315-1008.230 91.724 17.150 55-999.020 95.084 -17.150 316-999.020 95.084 17.150 56-989.824 98.482 -17.150 317-989.824 98.482 17.150 57-980.642 101.918 -17.150 318-980.642 101.918 17.150 58-971.475 105.392 -17.150 319-971.475 105.392 17.150 59-962.322 108.904 -17.150 320-962.322 108.904 17

21、.150 60-953.184 112.454 -17.150 321-953.184 112.454 17.150 61-944.060 116.041 -17.150 322-944.060 116.041 17.150 62-934.951 119.667 -17.150 323-934.951 119.667 17.150 63-925.856 123.331 -17.150 324-925.856 123.331 17.150 64-916.776 127.033 -17.150 325-916.776 127.033 17.150 65-907.710 130.772 -17.15

22、0 326-907.710 130.772 17.150 66-898.659 134.550 -17.150 327-898.659 134.550 17.150 67-889.622 138.366 -17.150 328-889.622 138.366 17.150 68-880.599 142.219 -17.150 329-880.599 142.219 17.150 69-871.591 146.111 -17.150 330-871.591 146.111 17.150 70-862.598 150.040 -17.150 331-862.598 150.040 17.150 7

23、1-853.619 154.008 -17.150 332-853.619 154.008 17.150 72-844.654 158.013 -17.150 333-844.654 158.013 17.150 73-835.704 162.057 -17.150 334-835.704 162.057 17.150 74-826.769 166.138 -17.150 335-826.769 166.138 17.150 75-817.847 170.258 -17.150 336-817.847 170.258 17.150 76-808.941 174.415 -17.150 337-

24、808.941 174.415 17.150 77-800.049 178.611 -17.150 338-800.049 178.611 17.150 78-791.171 182.844 -17.150 339-791.171 182.844 17.150 79-782.308 187.115 -17.150 340-782.308 187.115 17.150 80-773.459 191.424 -17.150 341-773.459 191.424 17.150 81-764.625 195.772 -17.150 342-764.625 195.772 17.150 82-755.

25、805 200.157 -17.150 343-755.805 200.157 17.150 83-747.000 204.580 -17.150 344-747.000 204.580 17.150 84-737.663 201.238 -17.150 345-737.663 201.238 17.150 85-728.325 197.937 -17.150 346-728.325 197.937 17.150 86-718.988 194.679 -17.150 347-718.988 194.679 17.150 87-709.650 191.463 -17.150 348-709.65

26、0 191.463 17.150 88-700.313 188.288 -17.150 349-700.313 188.288 17.150 89-690.975 185.156 -17.150 350-690.975 185.156 17.150 90-681.638 182.066 -17.150 351-681.638 182.066 17.150 91-672.300 179.018 -17.150 352-672.300 179.018 17.150 92-662.963 176.012 -17.150 353-662.963 176.012 17.150 93-653.625 17

27、3.048 -17.150 354-653.625 173.048 17.150 94-644.288 170.126 -17.150 355-644.288 170.126 17.150 95-634.950 167.246 -17.150 356-634.950 167.246 17.150 96-625.613 164.408 -17.150 357-625.613 164.408 17.150 97-616.275 161.612 -17.150 358-616.275 161.612 17.150 98-606.938 158.858 -17.150 359-606.938 158.

28、858 17.150 99-597.600 156.147 -17.150 360-597.600 156.147 17.150 100-588.263 153.477 -17.150 361-588.263 153.477 17.150 101-578.925 150.849 -17.150 362-578.925 150.849 17.150 102-569.588 148.264 -17.150 363-569.588 148.264 17.150 103-560.250 145.720 -17.150 364-560.250 145.720 17.150 104-550.913 143

29、.219 -17.150 365-550.913 143.219 17.150 105-541.575 140.759 -17.150 366-541.575 140.759 17.150 106-532.238 138.342 -17.150 367-532.238 138.342 17.150 107-522.900 135.966 -17.150 368-522.900 135.966 17.150 108-513.563 133.633 -17.150 369-513.563 133.633 17.150 109-504.225 131.341 -17.150 370-504.225

30、131.341 17.150 110-494.888 129.092 -17.150 371-494.888 129.092 17.150 111-485.550 126.885 -17.150 372-485.550 126.885 17.150 112-476.213 124.720 -17.150 373-476.213 124.720 17.150 113-466.875 122.597 -17.150 374-466.875 122.597 17.150 114-457.538 120.515 -17.150 375-457.538 120.515 17.150 115-448.20

31、0 118.476 -17.150 376-448.200 118.476 17.150 116-438.863 116.479 -17.150 377-438.863 116.479 17.150 117-429.525 114.524 -17.150 378-429.525 114.524 17.150 118-420.188 112.611 -17.150 379-420.188 112.611 17.150 119-410.850 110.740 -17.150 380-410.850 110.740 17.150 120-401.513 108.912 -17.150 381-401

32、.513 108.912 17.150 121-392.175 107.125 -17.150 382-392.175 107.125 17.150 122-382.838 105.380 -17.150 383-382.838 105.380 17.150 123-373.500 103.677 -17.150 384-373.500 103.677 17.150 124-364.163 102.017 -17.150 385-364.163 102.017 17.150 125-354.825 100.398 -17.150 386-354.825 100.398 17.150 126-3

33、45.488 98.821 -17.150 387-345.488 98.821 17.150 127-336.150 97.287 -17.150 388-336.150 97.287 17.150 128-326.813 95.794 -17.150 389-326.813 95.794 17.150 129-317.475 94.344 -17.150 390-317.475 94.344 17.150 130-308.138 92.935 -17.150 391-308.138 92.935 17.150 131-298.800 91.569 -17.150 392-298.800 9

34、1.569 17.150 132-289.463 90.245 -17.150 393-289.463 90.245 17.150 133-280.125 88.962 -17.150 394-280.125 88.962 17.150 134-270.788 87.722 -17.150 395-270.788 87.722 17.150 135-261.450 86.524 -17.150 396-261.450 86.524 17.150 136-252.113 85.368 -17.150 397-252.113 85.368 17.150 137-242.775 84.253 -17

35、.150 398-242.775 84.253 17.150 138-233.438 83.181 -17.150 399-233.438 83.181 17.150 139-224.100 82.151 -17.150 400-224.100 82.151 17.150 140-214.763 81.163 -17.150 401-214.763 81.163 17.150 141-205.425 80.217 -17.150 402-205.425 80.217 17.150 142-196.088 79.313 -17.150 403-196.088 79.313 17.150 143-

36、186.750 78.452 -17.150 404-186.750 78.452 17.150 144-177.413 77.632 -17.150 405-177.413 77.632 17.150 145-168.075 76.854 -17.150 406-168.075 76.854 17.150 146-158.738 76.118 -17.150 407-158.738 76.118 17.150 147-149.400 75.424 -17.150 408-149.400 75.424 17.150 148-140.063 74.773 -17.150 409-140.063

37、74.773 17.150 149-130.725 74.163 -17.150 410-130.725 74.163 17.150 150-121.388 73.596 -17.150 411-121.388 73.596 17.150 151-112.050 73.070 -17.150 412-112.050 73.070 17.150 152-102.713 72.587 -17.150 413-102.713 72.587 17.150 153-93.375 72.145 -17.150 414-93.375 72.145 17.150 154-84.038 71.746 -17.1

38、50 415-84.038 71.746 17.150 155-74.700 71.388 -17.150 416-74.700 71.388 17.150 156-65.363 71.073 -17.150 417-65.363 71.073 17.150 157-56.025 70.800 -17.150 418-56.025 70.800 17.150 158-46.688 70.569 -17.150 419-46.688 70.569 17.150 159-37.350 70.379 -17.150 420-37.350 70.379 17.150 160-28.013 70.232

39、 -17.150 421-28.013 70.232 17.150 161-18.675 70.127 -17.150 422-18.675 70.127 17.150 162-9.338 70.064 -17.150 423-9.338 70.064 17.150 1630.000 70.043 -17.150 4240.000 70.043 17.150 1649.338 70.064 -17.150 4259.338 70.064 17.150 16518.675 70.127 -17.150 42618.675 70.127 17.150 16628.013 70.232 -17.15

40、0 42728.013 70.232 17.150 16737.350 70.379 -17.150 42837.350 70.379 17.150 16846.688 70.569 -17.150 42946.688 70.569 17.150 16956.025 70.800 -17.150 43056.025 70.800 17.150 17065.363 71.073 -17.150 43165.363 71.073 17.150 17174.700 71.388 -17.150 43274.700 71.388 17.150 17284.038 71.746 -17.150 4338

41、4.038 71.746 17.150 17393.375 72.145 -17.150 43493.375 72.145 17.150 174102.713 72.587 -17.150 435102.713 72.587 17.150 175112.050 73.070 -17.150 436112.050 73.070 17.150 176121.388 73.596 -17.150 437121.388 73.596 17.150 177130.725 74.163 -17.150 438130.725 74.163 17.150 178140.063 74.773 -17.150 4

42、39140.063 74.773 17.150 179149.400 75.424 -17.150 440149.400 75.424 17.150 180158.738 76.118 -17.150 441158.738 76.118 17.150 181168.075 76.854 -17.150 442168.075 76.854 17.150 182177.413 77.632 -17.150 443177.413 77.632 17.150 183186.750 78.452 -17.150 444186.750 78.452 17.150 184196.088 79.313 -17

43、.150 445196.088 79.313 17.150 185205.425 80.217 -17.150 446205.425 80.217 17.150 186214.763 81.163 -17.150 447214.763 81.163 17.150 187224.100 82.151 -17.150 448224.100 82.151 17.150 188233.438 83.181 -17.150 449233.438 83.181 17.150 189242.775 84.253 -17.150 450242.775 84.253 17.150 190252.113 85.3

44、68 -17.150 451252.113 85.368 17.150 191261.450 86.524 -17.150 452261.450 86.524 17.150 192270.788 87.722 -17.150 453270.788 87.722 17.150 193280.125 88.962 -17.150 454280.125 88.962 17.150 194289.463 90.245 -17.150 455289.463 90.245 17.150 195298.800 91.569 -17.150 456298.800 91.569 17.150 196308.13

45、8 92.935 -17.150 457308.138 92.935 17.150 197317.475 94.344 -17.150 458317.475 94.344 17.150 198326.813 95.794 -17.150 459326.813 95.794 17.150 199336.150 97.287 -17.150 460336.150 97.287 17.150 200345.488 98.821 -17.150 461345.488 98.821 17.150 201354.825 100.398 -17.150 462354.825 100.398 17.150 2

46、02364.163 102.017 -17.150 463364.163 102.017 17.150 203373.500 103.677 -17.150 464373.500 103.677 17.150 204382.838 105.380 -17.150 465382.838 105.380 17.150 205392.175 107.125 -17.150 466392.175 107.125 17.150 206401.513 108.912 -17.150 467401.513 108.912 17.150 207410.850 110.740 -17.150 468410.850 110.740 17.150 208420.188 112.611 -17.150 469420.188 112.611 17.150 209429.525 114.524 -17.150 470429.525 114.524 17.150 210438.863 116.479 -17.150 471438.863 116.479 17.150 211448.200 11