长兴港大桥荷载试验报告

-/r/nPAGE/r/n.z./r/n目录/r/n/r/n/r/n1/r/n、试验桥概况/r/n/r/n1/r/n/r/n1.1/r/n工程概况/r/n/r/n1/r/n/r/n2/r/n、桥梁检查及试验目的/r/n/r/n2/r/nHYPERLINK/r/n浙江省交通厅质量监视站〔浙交监[1999]231号〕/r/n四/r/n、/r/n检测/r/n内容及方法/r/n4.1、调查桥梁构造的现有状况/r/n在试验前对桥梁构造的现有状况进展调查，可全面地了解构造初始状态，以便于编制切实可行的试验方案，同时到达合理评价试验测试结果、正确解释试验现象的目的。主要内容包括：/r/n〔一〕线形测量，主要是主桥标高测量；/r/n〔二〕构造各部件几何尺寸和主要构件的细部尺寸；/r/n〔三〕构造外表损缺情况以及构件变形情况。检测评定的范围包括可及主要部位的桥面系、桥跨构造和下部构造。/r/n〔1〕桥面系/r/n1〕桥面铺装平整度情况；/r/n2〕护栏有无歪斜及构件混凝土有无开裂；/r/n3〕桥面排水设施有无堵塞和漏水；/r/n4〕伸缩缝是否错位、不平整等。/r/n〔2〕上部构造/r/n1)混凝土有无裂缝、渗水、外表风化、剥落、露筋和钢筋锈蚀，有无活性骨料硅碱反响引起的整体龟裂现象。/r/n2)预应力钢束锚固区段混凝土有无开裂，沿预应力筋的混凝土外表有无纵向裂缝。/r/n3〕/r/n吊杆是否裸露，钢绞线有无锈蚀情况/r/n。/r/n〔3〕下部构造/r/n下部构造包括：支座、盖梁、墩身/r/n等。/r/n4.2、构造静载试验/r/n本桥静载试验选择主桥进展。主要测试内容如下所示：/r/n1/r/n、拱肋、系杆弯矩，拱脚轴力，吊杆索力/r/n。/r/n在/r/n拱肋及系杆的跨中、四分点及拱脚粘贴/r/n应变计，测试试验荷载作用下应变。由静态应变测试仪/r/n武汉HY/r/n采集信息，通过电脑自动记录。/r/n2/r/n、/r/n系杆/r/n竖向挠度/r/n系杆/r/n挠度均采用精细水准仪进展测量。/r/n3/r/n、偏载效应及其增大系数。/r/n主桥主要荷载试验工况分别测试中载工况及偏载工况，进而分析出偏载效应，通过与理论计算值的比拟，确定偏载增大系数。/r/n4.3、构造动载试验/r/n脉动试验是在桥面无任何交通荷载以及桥梁附近无规则振源的情况下，测定桥跨构造由于桥址处风荷载、地脉动、水流等随机荷载激振而引起的桥跨构造/r/n的/r/n微幅振动响应/r/n。/r/n脉动试验测试内容包括/r/n主桥/r/n的振型、临界阻尼比和固有模态频率。/r/n五/r/n、/r/n长兴港大桥/r/n外观/r/n检查结果/r/n为对试验构造现状有充分的了解，检测单位于20/r/n1/r/n3/r/n年/r/n1/r/n月/r/n14/r/n日至/r/n15日〔荷载试验准备阶段/r/n〕，参照/r/n"公路桥梁技术状况评定标准"JTG/TH21-2011/r/n和省公路管理局浙公路[2005]115号文件的有关要求，对/r/n长兴港大桥/r/n进展了外观质量检查/r/n，病害主要表现为护栏破损〔已修补〕，桥面铺装纵向裂缝，L=7m，D=01mm〔已修复〕/r/n。/r/n桥梁总体状况良好。/r/n图5.1/r/n护栏破损/r/n图5.2/r/n铺装纵向裂缝/r/n根据现场的检测条件和外观情况，运用ZC3-A数显混凝土回弹仪对拱肋等构件进展了抗压强度检测，测区的分布根据"回弹法检测混凝土抗压强度技术规程"的要求来确定。测试结果见下表：/r/n编号/r/n混凝土抗压强度〔MPa〕/r/n推定强度匀质系数/r/n平均强度匀质系数/r/n评定/r/n标度值/r/n构件强度状态/r/n设计值/r/n实测/r/n实测/r/n实测/r/n平均值/r/n最小值/r/n推定值/r/n1/r/n50/r/n57.0/r/n53.0/r/n53.4/r/n1.07/r/n1.14/r/n1/r/n良好/r/n2/r/n50/r/n54.3/r/n48.0/r/n52.5/r/n1.05/r/n1.09/r/n1/r/n良好/r/n3/r/n50/r/n52.2/r/n45.0/r/n51.7/r/n1.03/r/n1.04/r/n1/r/n良好/r/n4/r/n50/r/n49.2/r/n43.0/r/n51.1/r/n1.02/r/n0.98/r/n1/r/n良好/r/n5/r/n50/r/n48.7/r/n47/r/n.0/r/n50.9/r/n1.02/r/n0.97/r/n1/r/n良好/r/n6/r/n50/r/n48.2/r/n44.0/r/n50.4/r/n1.01/r/n0.96/r/n1/r/n良好/r/n7/r/n50/r/n54.2/r/n48.0/r/n52.1/r/n1.04/r/n1.08/r/n1/r/n良好/r/n8/r/n50/r/n54.7/r/n47.0/r/n52.9/r/n1.06/r/n1.09/r/n1/r/n良好/r/n9/r/n50/r/n56.9/r/n54.0/r/n43.2/r/n0.86/r/n1.14/r/n1/r/n良好/r/n10/r/n50/r/n55.0/r/n47.0/r/n53.1/r/n1.06/r/n1.10/r/n1/r/n良好/r/n从上述抽检的混凝土构件检测结果可以看出，抽检拱肋的强度标定值均为1，说明该构件处于良好的状态。/r/n六/r/n、桥面线形测量分析结果/r/n长兴港大桥/r/n主桥桥面线形测量采用精细水准仪进展，进而分析出桥面铺装的纵向线形。桥面线形测量测点布置如下列图/r/n6/r/n.1所示：/r/n图/r/n6.1/r/n桥面线性测量测点布置图/r/n桥面线形测量结果如下表/r/n6/r/n./r/n1所示：/r/n表/r/n6/r/n.1桥面线形测量结果分析表/r/n测点位/r/n置编号/r/n理论值/r/n实测值/r/n东侧/r/n桥面相对高程〔mm〕/r/n西侧/r/n桥面相对高程〔mm〕/r/n1/r/n0/r/n0/r/n2/r/n54/r/n57.58/r/n3/r/n73.68/r/n63.49/r/n4/r/n73.96/r/n63.86/r/n5/r/n73.2/r/n62.88/r/n6/r/n50.91/r/n49.57/r/n7/r/n1.59/r/n-1.28/r/n图/r/n6.2/r/n桥梁纵断面线形图/r/n由表/r/n6/r/n.1及图/r/n6/r/n./r/n2/r/n可以看出，/r/n东侧桥面跨中三点标高略高于西侧。/r/n大桥/r/n加固/r/n后桥面/r/n没有突变点，/r/n竖曲线较平顺，桥面纵向线形较好。/r/n七/r/n、静载试验及分析/r/n7/r/n.1、试验荷载确实定原则/r/n静力试验荷载采用载重汽车进展等效加载。就*一检验工程而言，根据"大跨径混凝土桥梁的试验方法"中的规定，桥梁荷载试验一般采用根本荷载，其中静力试验荷载的效率系数/r/nη/r/n取值范围为/r/n1.05/r/n≥η≥/r/n0.8/r/n；根据浙江省交通厅质量监视站"关于标准桥梁荷载及试桩试验行为的通知"的有关规定，静力试验荷载的效率系数/r/nη/r/n取值范围为/r/n1.05/r/n≥η≥/r/n0.9/r/n。在实际加载过程中，为了减少试验时间及简化工况的目的，在保证主要检验工程荷载系数满足要求的前提下，可适当减小*些工程的荷载效率系数。但荷载效率系数的增大必须保证构造的平安。/r/n为了准确进展荷载试验，试验前进展了理论计算。本桥采用MIDAS20/r/n10/r/n程序进展了构造静力计算、活载效应计算及相应的加载效率的计算。/r/nMIDAS20/r/n10/r/n程序构造计算简图见图/r/n7.1/r/n：/r/n图/r/n7.1/r/n长兴港大桥/r/n计算模型/r/n通过静载试验，测定桥梁构造的静应变、静挠度，以便确定桥梁的真实受力状态、使用性能。以此检验构造的实际工作性能、平安度，并对桥梁的实际承载力和实际刚度作出可靠评价/r/n。/r/n7/r/n.2、试验荷载与分级加载实施/r/n试验时采用/r/n双/r/n后轴自卸车，/r/n各车车重如下所示/r/n就*一加载工况而言，其所需加载车辆和加载位置，是根据设计荷载产生控制截面内力和变形的最不利效应换算而得。/r/n加载位置和加载车数量根据以下原则确定：/r/n1、用尽可能少的加载车辆到达最适宜的试验荷载效率；/r/n2、在满足荷载效率及到达试验目的的情况下，尽量简化加载工况；/r/n3、前后加载工况应互相兼顾，加载车辆合理调配。/r/n7/r/n.3、/r/n测试截面与试验工况/r/n1、测试截面的测点布置/r/n主桥各工况的加载车详细位置见图/r/n7.2/r/n～/r/n7./r/n5/r/n。/r/n与静载试验内容对应，纵桥向按最不利位置布载；相应的横桥向有两种工况〔中载、偏载〕，偏载主要是为了寻求横向分布的最不利状态，静载试验设7个工况：/r/n1〕工况Ⅰ：中载作用下/r/n拱肋S2/r/n截面最大正弯矩；中载作用下系杆/r/nS1/r/n截面最大正弯矩/r/n和挠度/r/n；中载作用下/r/n吊/r/n杆/r/nS8/r/n截面最大/r/n索力，/r/n共需/r/n6/r/n辆加载车；/r/n2〕工况Ⅱ：偏载作用下/r/n拱肋S2/r/n截面最大正弯矩；偏载作用下系杆/r/nS1/r/n截面最大正弯矩和挠度；/r/n偏/r/n载作用下/r/n吊/r/n杆/r/nS8/r/n截面最大/r/n索力/r/n；共需/r/n6/r/n辆加载车/r/n3〕工况Ⅲ：中载作用下/r/n拱肋S4/r/n截面最大正弯矩；中载作用下/r/nS3/r/n截面最大正弯矩和挠度；/r/n中载作用下S7截面索力，/r/n共需/r/n6/r/n辆加载车；/r/n4〕工况Ⅳ：/r/n偏/r/n载作用下/r/n拱肋S4/r/n截面最大正弯矩；/r/n偏/r/n载作用下/r/nS3/r/n截面最大正弯矩和挠度；/r/n偏载作用下S7截面索力，/r/n共需/r/n6/r/n辆加载车；/r/n5〕工况Ⅴ：中载作用下/r/n拱肋S4/r/n截面最不利负弯矩；中载作用下/r/n系杆S3/r/n截面最大负弯矩和挠度；/r/n中载作用下S7截面索力，/r/n共需/r/n6/r/n辆加载车/r/n6〕工况Ⅵ：偏载作用下/r/n拱肋S4/r/n截面最不利负弯矩；偏载作用下/r/nS3/r/n截面最大负弯矩和挠度；/r/n偏载作用下S7截面索力，/r/n共需/r/n6/r/n辆加载车。/r/n7〕工况Ⅶ：中载作用下拱脚/r/nS/r/n5/r/n截面最大轴力；/r/n吊/r/n杆/r/nS6/r/n最大/r/n索/r/n力；共需/r/n8/r/n辆加载车。/r/n具体工况为：/r/n工况测试工程详细说明表表/r/n7.1/r/n工况/r/n观测工程/r/n仪器/r/n车数/r/nⅠ/r/n、/r/nⅡ/r/n1、拱肋S2、系杆S1截面最大正弯距(应力)/r/n应变计/r/n6/r/n2、系杆S1截面最大挠曲变形〔挠度〕/r/n精细水准仪/r/n3、吊杆S8截面最大索力/r/n索力仪/r/nⅢ/r/n、/r/nⅣ/r/n1、拱肋S4、系杆S3截面最大正弯距(应力)/r/n应变计/r/n6/r/n2、系杆S3截面最大挠曲变形〔挠度〕/r/n精细水准仪/r/n3、吊杆S7/r/n截面最大索力/r/n索力仪/r/nⅤ/r/n、/r/nⅥ/r/n1、拱肋S4、系杆S3截面最大负弯距(应力)/r/n应变计/r/n6/r/n2、吊杆S7截面最大索力/r/n索力仪/r/nⅦ/r/n1、/r/n拱脚S5/r/n截面最大/r/n轴力/r/n应变计/r/n8/r/n2、/r/n吊杆S6截面最大索力/r/n索力仪/r/n图/r/n7.2/r/n工况一、二试验荷载布置图/r/n图/r/n7.3/r/n工况三/r/n、四/r/n试验荷载布置图/r/n图/r/n7.4/r/n工况/r/n五、六/r/n试验荷载布置图/r/n图/r/n7.5/r/n工况/r/n七/r/n试验荷载布置图/r/n7/r/n.4、/r/n测试仪器及测量方法/r/n1、试验仪器/r/n截面应变采用/r/n大理石胶粘贴/r/n应变计/r/n，数据采集记录使用静态应变测量仪/r/n武汉HY/r/n；/r/n系杆/r/n挠度/r/n采用/r/n水准仪定点定站/r/n测试/r/n。/r/n2、量测方法/r/n首先依测点位置实施打磨找平，之后粘贴/r/n应变计/r/n,将其用传输线连接到无线信号发射器/r/n；/r/n将无线信号接收器连接至电脑/r/n，调试设备，进展正式加载试验。/r/n接线联机后，进展调试工作，检查各个设备、测试组件是否处于良好的可靠状态。试验中为尽可能减少混凝土流变特性的影响，采用加载到位后，关闭汽车发动机，持续5分钟以上，待/r/n混凝土材料/r/n完全稳定之后再进展记录；卸载后10分钟以上，再进展一次重复加载，以便使构造恢复弹性变形，消除塑性剩余变形。/r/n每一个加载工况均重复两次，以使每一工况获取可靠试验资料。/r/n7/r/n.5、/r/n静载试验/r/n应变测试/r/n结果分析/r/n1、试验荷载作用下控制截面应变比照分析/r/n本次试验的应变测试通过在测试断面粘贴/r/n应变计/r/n，测得混凝土外表应变。考虑荷载横向分布系数并按平面假定推算出截面上最大应变值并与计算值比拟。/r/n应变测点编号如所示/r/n长兴港大桥/r/n各工况/r/n控制截面测点应变实测值与理论值比拟，见/r/n下表/r/n。/r/n表/r/n7./r/n2/r/n工况一测点应变及校验系数表单位：/r/nμε/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况1/r/nS1、S2/r/n1/r/n-24.2/r/n-54/r/n0.45/r/n2/r/n-17.3/r/n-78/r/n0.22/r/n3/r/n--/r/n-78/r/n--/r/n4/r/n--/r/n-54/r/n--/r/n5/r/n-28.7/r/n-72/r/n0.40/r/n6/r/n-21.4/r/n-29/r/n0.74/r/n7/r/n--/r/n14/r/n--/r/n8/r/n-17/r/n-72/r/n0.24/r/n9/r/n--/r/n-29/r/n--/r/n10/r/n--/r/n14/r/n--/r/n校验系数平均值/r/n0.41/r/n表/r/n7./r/n3/r/n工况二测点应变及校验系数表单位：/r/nμε/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况2/r/nS1、S2/r/n1/r/n-31.5/r/n-74/r/n0.43/r/n2/r/n-26.6/r/n-105/r/n0.25/r/n3/r/n-37.3/r/n-97/r/n0.38/r/n4/r/n-22.4/r/n-83/r/n0.27/r/n5/r/n--/r/n-50/r/n--/r/n6/r/n--/r/n9/r/n--/r/n7/r/n--/r/n68/r/n--/r/n8/r/n-51.4/r/n-47/r/n1.09/r/n9/r/n--/r/n-19/r/n--/r/n10/r/n--/r/n9/r/n--/r/n校验系数平均值/r/n0.49/r/n表/r/n7./r/n4/r/n工况三测点应变及校验系数表单位：/r/nμε/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况3/r/nS3、S4/r/n11/r/n-52.4/r/n-125/r/n0.42/r/n12/r/n-40.5/r/n-87/r/n0.47/r/n13/r/n-34.8/r/n-125/r/n0.28/r/n14/r/n-23.3/r/n-87/r/n0.27/r/n15/r/n-55.4/r/n-101/r/n0.55/r/n16/r/n-20.9/r/n-27/r/n0.77/r/n17/r/n21.3/r/n48/r/n0.44/r/n18/r/n-46.2/r/n-101/r/n0.46/r/n19/r/n-23.2/r/n-27/r/n0.86/r/n20/r/n11.8/r/n48/r/n0.25/r/n校验系数平均值/r/n0.49/r/n表/r/n7./r/n5/r/n工况四测点应变及校验系数表单位：/r/nμε/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况4/r/nS3、S4/r/n11/r/n--/r/n-163/r/n--/r/n12/r/n-30.4/r/n-117/r/n0.26/r/n13/r/n-42.9/r/n-85/r/n0.50/r/n14/r/n-30.3/r/n-60/r/n0.51/r/n15/r/n-41.7/r/n-131/r/n0.32/r/n16/r/n-13.1/r/n-36/r/n0.36/r/n17/r/n--/r/n60/r/n--/r/n18/r/n-56/r/n-70/r/n0.80/r/n19/r/n--/r/n-17/r/n--/r/n20/r/n14.4/r/n36/r/n0.40/r/n校验系数平均值/r/n0.45/r/n表/r/n7./r/n6/r/n工况五应变测点应变及校验系数表单位：/r/nμε/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况5/r/nS3、S4/r/n11/r/n30.7/r/n90/r/n0.34/r/n12/r/n37.5/r/n71/r/n0.53/r/n13/r/n27.9/r/n92/r/n0.30/r/n14/r/n21.8/r/n73/r/n0.30/r/n15/r/n10.4/r/n27/r/n0.39/r/n16/r/n-16.9/r/n-30/r/n0.56/r/n17/r/n-55.4/r/n-87/r/n0.64/r/n18/r/n--/r/n28/r/n--/r/n19/r/n-19/r/n-30/r/n0.63/r/n20/r/n-47.5/r/n-88/r/n0.54/r/n校验系数平均值/r/n0.47/r/n表/r/n7./r/n7/r/n工况六应变测点应变及校验系数表单位：/r/nμ/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况6/r/nS3、S4/r/n11/r/n26.4/r/n115/r/n0.23/r/n12/r/n24.8/r/n91/r/n0.27/r/n13/r/n35.4/r/n32/r/n1.11/r/n14/r/n--/r/n14/r/n--/r/n15/r/n--/r/n66/r/n--/r/n16/r/n--/r/n4/r/n--/r/n17/r/n-39.7/r/n-57/r/n0.70/r/n18/r/n7.8/r/n22/r/n0.35/r/n19/r/n--/r/n-19/r/n--/r/n20/r/n-64.1/r/n-61/r/n1.05/r/n校验系数平均值/r/n0.62/r/n表/r/n7./r/n8/r/n工况七应变测点应变及校验系数表单位：/r/nμ/r/n工况〔满载〕/r/n测试截面/r/n测点编号/r/n试验值/r/n①/r/n理论值/r/n②/r/n校验系数/r/n①/r/n//r/n②/r/n工况7/r/nS5/r/n21/r/n-51.5/r/n-60/r/n0.86/r/n22/r/n-18.3/r/n-28/r/n0.65/r/n23/r/n--/r/n5/r/n--/r/n24/r/n-38.1/r/n-60/r/n0.64/r/n25/r/n-15.9/r/n-28/r/n0.57/r/n26/r/n--/r/n5/r/n--/r/n校验系数平均值/r/n0.68/r/n由表/r/n7./r/n2/r/n～/r/n7./r/n8/r/n中/r/n数据/r/n可见，/r/n桥梁/r/n工况一/r/n～/r/n五/r/n控制截面/r/n各测点应变校验系数除极个别测点稍大外，绝大局部测点/r/n实测应变/r/n均小于/r/n相应的理论计算值/r/n；绝大局部测点应变校验系数及各工况应变校验系数均值满足/r/n校验系数规定/r/n的/r/n范围/r/n〔小于/r/n1.0/r/n5〕，这/r/n说明构造的实际承载力/r/n能/r/n满足/r/n设计/r/n荷载使用要求，且有一定的平安储藏；/r/n试验构造实测剩余应变/r/n绝大局部均/r/n不大于20%，说明/r/n主桥/r/n构造在试验荷载作用下处于弹性工作状态/r/n。/r/n7/r/n.6/r/n、静载试验/r/n挠度测试/r/n结果分析/r/n长兴港大桥/r/n控制截面测点/r/n挠度/r/n实测值与理论值比拟，见表/r/n7./r/n9/r/n。/r/n表/r/n7./r/n9/r/n控制截面测点挠度及校验系数表/r/n工况/r/n挠度测点/r/n试验实测值/r/n①/r/n(mm)/r/n理论计算值/r/n②/r/n(mm)/r/n挠度校验系数/r/n①/r/n//r/n②/r/n工况1/r/n桥面/r/n西/r/n侧/r/n-6.8/r/n-10.36/r/n0.66/r/n桥面/r/n东/r/n侧/r/n-6.4/r/n-10.36/r/n0.62/r/n校验系数平均值/r/n0.64/r/n工况2/r/n桥面/r/n西/r/n侧/r/n-2.9/r/n-5.8/r/n0.50/r/n桥面/r/n东/r/n侧/r/n-10.1/r/n-11.9/r/n0.85/r/n校验系数平均值/r/n0.67/r/n工况3/r/n桥面/r/n西/r/n侧/r/n-7.8/r/n-13.48/r/n0.58/r/n桥面/r/n东/r/n侧/r/n-10.2/r/n-13.48/r/n0.76/r/n校验系数平均值/r/n0.62/r/n工况4/r/n桥面/r/n西/r/n侧/r/n-6.5/r/n-8.2/r/n0.79/r/n桥面/r/n东/r/n侧/r/n-13.7/r/n-15.3/r/n0.90/r/n校验系数平均值/r/n0.85/r/n由表/r/n7./r/n9/r/n中/r/n数据/r/n可见，/r/n桥梁各/r/n挠度/r/n测点/r/n在各工况的/r/n实测挠度/r/n均小于/r/n相应的理论计算值，各工况在满载情况下的测点挠度校验系数/r/n均小于1.0；各测点挠度校验系数及各工况挠度校验系数均值满足/r/n"/r/n大跨径混凝土桥梁的试验/r/n"关于/r/n挠度/r/n校验系数的规定/r/n；主桥/r/n构造的实际/r/n刚度能/r/n满足/r/n设计/r/n荷载使用要求，且有一定的平安储藏；/r/n试验构造实测剩余/r/n挠度均/r/n不大于20%，说明构造在试验荷载作用下/r/n尚/r/n处于弹性工作状态。/r/n7.7/r/n、静载试验/r/n吊杆索力测试/r/n结果分析/r/n长兴港大桥/r/n控制截面/r/n吊杆索力/r/n实测值与理论值比拟，见表/r/n7.10/r/n。/r/n表7.10控制截面测点挠度及校验系数表/r/n工况/r/n吊杆/r/n试验实测值/r/n①/r/n(/r/nKN/r/n)/r/n理论计算值/r/n②/r/n(/r/nKN/r/n)/r/n挠度校验系数/r/n①/r/n//r/n②/r/n工况1/r/n桥面/r/n西/r/n侧/r/n131.5/r/n179.5/r/n0.73/r/n桥面/r/n东/r/n侧/r/n165.1/r/n179.5/r/n0.92/r/n校验系数平均值/r/n0.83/r/n工况2/r/n桥面/r/n西/r/n侧/r/n81.4/r/n99.7/r/n0.82/r/n桥面/r/n东/r/n侧/r/n176.2/r/n206.1/r/n0.85/r/n校验系数平均值/r/n0.84/r/n工况3/r/n桥面/r/n西/r/n侧/r/n93.72/r/n154/r/n0.61/r/n桥面/r/n东/r/n侧/r/n113.04/r/n154/r/n0.73/r/n校验系数平均值/r/n0.67/r/n工况4/r/n桥面/r/n西/r/n侧/r/n67.5/r/n85.6/r/n0.79/r/n桥面/r/n东/r/n侧/r/n140.8/r/n177.1/r/n0.80/r/n校验系数平均值/r/n0.79/r/n工况7/r/n桥面/r/n西/r/n侧/r/n--/r/n162.3/r/n--/r/n桥面/r/n东/r/n侧/r/n130.6/r/n162.3/r/n0.80/r/n校验系数平均值/r/n0.8/r/n由表/r/n7./r/n10/r/n中/r/n数据/r/n可见，/r/n桥梁工况一～/r/n工况四及工况七/r/n控制截面/r/n各/r/n吊杆/r/n校验系数除极个别测点稍大外，绝大局部测点/r/n实测/r/n索力/r/n均小于/r/n相应的理论计算值/r/n；绝大局部测点/r/n索力/r/n校验系数及各工况/r/n索力/r/n校验系数均值满足/r/n校验系数规定/r/n的/r/n范围/r/n〔小于/r/n1.0/r/n5〕，这/r/n说明构造的实际承载力/r/n能/r/n满足/r/n设计荷载使用要求，且有一定的平安储藏。/r/n八/r/n、动载试验及脉动试验分析/r/n8/r/n./r/n1/r/n、主桥脉动试验分析/r/n长兴港大桥/r/n全桥共设置/r/n5/r/n个模态测试点，测点布置参见/r/n图8.1/r/n，测试结果如下所示。/r/n图8.1/r/n模态测点位置图/r/n8/r/n./r/n长兴港/r/n特大桥主桥实测/r/n时域曲线、频域曲线如图。/r/n分析建模如图/r/n8./r/n2/r/n～8./r/n3/r/n，主桥自振特性测试频谱图、实测竖向一阶、二阶、三阶振型四视图如图/r/n8./r/n4/r/n～/r/n图/r/n8./r/n5/r/n所示，用DHMA2.51分析的自振频率、阻尼及振型特征说明见表/r/n8/r/n./r/n1/r/n。/r/n表/r/n8/r/n./r/n1/r/n主桥实测自振频率与振型特征/r/n阶次/r/n实测频率〔Hz〕/r/n阻尼〔％〕/r/n振型说明/r/n1/r/n2./r/n35/r/n2.38/r/n主梁竖弯/r/n2/r/n3.52/r/n2.00/r/n主梁竖弯/r/n图/r/n8/r/n./r/n2/r/n动测分析建模图/r/n图/r/n8/r/n./r/n3/r/n长兴港/r/n特大桥主桥自振特性测试频谱图/r/n图/r/n8/r/n./r/n4/r/n主桥实测一阶竖弯振动四视图/r/n图/r/n8/r/n./r/n5/r/n主桥实测二阶竖弯振动四视图/r/n8/r/n.2自振频率理论计算/r/n长兴港/r/n特大桥主桥的自振特性计算采用专用有限元程序Midas/Civil进展建模。模型采用梁单元组成的组合单元理论模型计算复杂桥梁构造，全桥模型能准确模拟构件的空间位置、尺寸、材料特性、连接形式、初始内力和初始变形等，确立构造仿真分析的初始形态。因此可得到相对详尽、准确和可靠的分析结果。/r/n自振特性计算结果汇总如表/r/n8/r/n./r/n2/r/n，计算自振频率和振型图式见图/r/n8/r/n./r/n6/r/n～/r/n8./r/n7/r/n。/r/n表/r/n8.2/r/n计算自振频率、周期和主要振型说明/r/n阶次/r/n周期/r/n(s)/r/n频率/r/n(Hz)/r/n振型特点/r/n1/r/n0./r/n488/r/n2.050/r/n拱肋桥面竖向弯曲/r/n5/r/n0.265/r/n3.769/r/n桥面竖弯/r/n图/r/n8./r/n6/r/n主桥竖向/r/n理论/r/n一阶振型图/r/n图/r/n8/r/n./r/n7/r/n主桥竖向/r/n理论/r/n二阶振型图/r/n8./r/n3实测结果与理论计算比照分析/r/n实测频率结果与理论计算频率比拟见表/r/n8.3/r/n。从表中可以看出：/r/n一阶竖向振动/r/n实测值大于理论值，/r/n二阶竖向振动实测值和理论值相近，说明实际构造刚度与/r/n理论计算刚度/r/n吻合/r/n，构造刚度满足设计要求。