[毕业设计 论文 精品]铁路预应力混凝土简支梁桥设计

a1a0a2a311绪论1.1课题研究意义桥梁是铁路或公路跨越河流，山谷及其它障碍物的建筑物。桥梁的建成使道路保持畅通，为我国国民经济建设发挥了巨大的作用。钢筋混凝土桥具有可塑性强，省钢，耐久性好，维修费用少，噪音少，美观等特点。而简支梁在我国桥梁建设中也应用的非常广泛，因为其具有不受地基条件限制，适用于跨度不大（一般跨径46.612cma37a38a39a4042.3.2截面几何特性计算（跨中截面）a41a42a43a42a44a45a46a47a48a49a50a51a52a53a54a55a52a53a53a56tA()2cma53a57a58a59a60a61a62a63a64a65a66y()cma67a68a69a70a71a72a73a74I4(cm)a68a69a70a75a76a77a78a79a80a81a82y()cma83a67a68a84a67a68a85a86a67a6894859195960480.87782.26108.556100.536103.57129.2132.0127.4钢绞线重心到下缘距：2851754756130.45mm11a+=2.4正截面抗弯强度计算设跨中性轴位于上翼缘内（ixh）由aiyyRbxAR=得2yyiai47.1135010105.13mm11.6cm31.51920ARxhRb=（可）()00.40.421013.04578.78cmhx=（可）2.5预应力损失计算2.5.1钢丝回缩和分块拼装构件的接缝压缩损失s3钢判锥型锚头每端钢丝回缩及锚头损失变形对跨中的影响为4mm,即20.40.8cmL=已知钢丝束平均长度：a87a88a89a905244802244342244682243082243462243502439.02cm11T+=5s30.82.01065.6MPa2439.02=2.5.2锚头变形5g2.010MPaE=，4h3.410MPaE=钢筋混凝土的弹性模量比：5g4h2.0105.8823.410EE=锚固口摩擦损失为：k0.7613501026MPa=k0.070.07102671.81MPa=kkk0.07954.18MPa=2.5.3摩阻损失s4查表得55.0=，0015.0=k从张拉端至计算截面的管道长度，一般可取半径的平均值，即：24.612.3m2x=从张拉端至计算截面的长度上钢筋弯起角之和一般可采取各钢丝束的平均和，即：5.2365.3445.1055.3925.1054.0091069605222240.0045.0045.0072004080110.1843radq+=0.550.18430.001513.30.1213qkx+=+=查表，内插值得，0122011301130121301201142001.(.).=+=s4k0.1142954.18121.07MPa=2.5.4分批张拉混凝土压缩引起的应力损失s6a91a92a93a946考虑4L截面处的有关数据4L处净截面积为9286cm2,截面重心到梁底的距离为128.7cm,对重心轴的惯性矩I=53.34610,ej=128.7-21.4=107.32js6hyyij111cos22eNNnnANNAI=+yks3s4s6=2jks3s4yyij11-cos2eNnANAI=+ks3s4y2jyjj111cos2eNnANAI=+代入有关数据得2y=51.7847cmAy26954.1865.6109747.47MPa1011107.315.8951.78740.98320928653.3410=+故s60.0427747.4731.92MPa=2.5.5钢筋应力松弛引起的应力损失s2jy1350MPaR=传力锚固时，jyy747.47MPa0.5675MPaR=，故必须考虑s2又jyy0.65877.5MPaR2.6.2运营阶段混凝土正应力2M-g1166g15904道，到g9207g8145及线g17347设g3803g12573（48.1kN/m）g1147g10995的弯矩3M-g6454算均g18108g14667g17745g1147g10995的弯矩钢筋g20056g2164g5224力的g2524力3yy1y6409.951.7849331.9410aNA=a103a104a105a106933331.94100.765433.8310a=()()()5y230110111h26356.91083.2610.76535.53737.79957.3510aNMMyeyMYArII+=+=+=266.12kg/cm（g2399）ha2.8剪应力计算运营阶段处检算截面正应力外，尚需检算腹板剪应力由外荷载产生的剪应力为：Qg=92.39122466.32=d24.0524288.6kN2Q=h949Q=kN()gjdh0j0QSQQSbIbI+=+由预应力钢筋弯起产生的剪应力为：yjs0yj0QSQSbIbI=a127a128a129a13012其中，()yywywks2s3s4s6ywsin0.5sinQAA=+()ss2s1yw0.5sinQA=+梁截面处见应力检算()y954.180.537.3765.610931.925178.470.1833691.94MPaQ=()y0.537.3769.45178.470.183383.61MPaQ=+=()36361010288.6949.010530.2310391.9210526.5101.403MPa78077.941078079.0510+=+=为了便于计算，将支点处截面简化成T型截面（见图2-2）2.8.1换算截面特性()2020619207807802100199005.715178.4718825.09cmA=+=2j05.715178.4718529.4cmAA=2.8.2换算截面对顶部水平线的面积矩预应力筋重心到底部的距离:y1325107528252265214521152561.36mm56.136cm11a+=y21056.136153.864cma=()864.1531997847.5171.52210210783.10)78192(6.20+=S331758.9710cm=a131a132a133a132a134a135a136a137a138a139a140a14113换算截面对顶部水平线的面积矩864.1531992210210783.10)78192(6.20+=S331713.4710cm=2.8.3换算截面重心至面顶部水平线的面积矩301758.971093.4cm18825.09y=a142021093.4116.6cmy=a143净截面重心至面顶部水平线的面积矩3j1713.471092.47cm18529.40y=a144j21092.47117.5cmy=a145()786.2021012126.204.936.201926.201921213230+=I()()()22136.566.11619929626.202106.116786.20210+6479.0510cm=()233j120.6119220.619220.692.4721020.67812212I=+()()22136.565.11719926.202105.117786.20210+6477.9410cm=()()33021093.478(21093.4)29619921093.456.136530.2310cm2S=+=()()33j21092.477821092.4719921092.4756.136526.510cm2S=3636y1010775.3310526.51095.48810530.23100.589MPa78077.941078079.0510=hy5001.4030.5890.814MPa5.56MPa9090R=不需要配预应力筋a146a147a148a149142.9主应力计算桥规主拉应力作为斜裂缝检算的依据2xhyhxhy2zlhl22hR+=+其中：()yyjygdh0hxj0fi0jj00y0NNeNMMMeyYKyyAIAIII+=+yjyjy0dhff0j0j0hQSQSQSQQKSbIbIbIbI+=+对1/8截面梁肋处()()yks3s4s6s2yyw0.56cosNAA=+()()9686.02354282537.3789.4156.092.311096.6518.954+=kN7.3734=()()()()y12yyw0.56cos69.40.5637.37282523540.9686ssNAA=+=+kN34.465=hx2743734679.863734679.86(13043.4)107969286105.4131010=8271010665.575.46534310958275.465343472+872101073.510757961063.10262.1476476()()()266.251.12.1647.0553.078.402.4+=hx10.760.0944.53123.87MPa=+=（压）hx28.81.24.53123.07Pa=（压）()y954.1865.610935.770.5637.3723540.1833313.26kNQ=a150a151a152a15315()kN97.371833.023544.6937.375.0Qy=+=()36333hf1111661111216.45252.5410335.110293.9410317.910101.22305.413102305.66510351290317.91043377335.1101.563MPa2305.413102305.66510+=+=其主拉应力为2222hxhxzlhfl3.073.07=1.56322220.2Pa3.0MPaR+=+=为了防止出现沿应力方向的微裂缝，需检查主拉应力。按桥规要求，对截面进行主拉应力检算2hxhyhxhy2zlhfa0.622R+=+对于变截面处hx3.87MPa=由于未配预应力箍筋，故hy0=，hf1.563MPa=22hxhxzlhf22a223.873.871.5634.42MPa0.60.631.5MPa18.9MPa22R=+=+=符合要求错误！未指定书签。a154a155a156a157163T型桥台设计检算3.1设计资料:(1)桥跨资料：I级铁路，单线，平坡，曲线；(2)不等跨度216m224m+道渣槽钢筋混凝土粱，双侧人行道及栏杆。(3)设计活载：某铁水罐车专用活载(4)建筑材料：顶帽及道渣槽用200#钢筋混凝土；(5)台后填土为渗水土317kN/m=(6)桥台尺寸：填土高，基础埋深及有关尺寸见图(7)其他计算数据：梁g990道渣槽等线路设g3803及双侧1g1755g80g4497人行道g18337g18339为4g27g171kg49g18g80(混凝土g7529)，台顶道渣槽及线路设g3803=6.71N1d(1d为桥台g19283度，单g1313，g80)。3.2确定桥台尺寸3.3荷载计算3.3.1竖直恒载3.3.1.1桥跨恒载压力1N1115676481246137543kN2137543006596403869822kNmN(.).M.(.).=+=+=a158a159a160a161173.3.1.2桥台自重a162a163a164a165a166a167a168a169a170a171a172a173a174a175a176a177a178a1793a180a181a182a183a184a1793a185a186a187a182a183a188a189a190a191a179a183a192a193a194a187a195kNma196a197a198a199a200386.92.9821153.74a201a202a203a204a160a205a206a198a207a208a20919.6523