支架预压沉降观测分析实施报告

1、吉安赣江特大桥13#、14#墩三角形挂篮预压沉降观测分析总结报告编制：审核：审批：监理工程师：中铁二十二局集团第四工程有限公司蒙华项目经理部2017年 10月 23日.吉安赣江特大桥13#、14#挂篮预压沉降观测分析总结报告一、预压目的为了确保挂篮施工安全，减少挂篮的非弹性变形, 获取弹性变形参数 , 得出压重与挂篮本身的变形关系 , 为挂篮施工和线性控制提供挂篮弹性挠度计算的可靠依据 , 保证施工质量和安全，对挂篮进行加载试验检验，消除整个挂篮的塑性变形，测量出挂篮的弹性变形。二、 预压方法a、预压加载按照加压荷载的0%、 20%、40%、60%、80%、100%、110%进行，布载截面形式

2、应模拟梁体荷载分布。加载顺序尽可能模拟混凝土浇筑顺序。在加载前0%时先进行测量，第一次加载箱梁底板及腹板处，加载至20%，依次 40%、60%、80%、100%、，加载至 110%，采用 1m×1m×0.62m 类型混凝土预制块231 块。具体加载顺序详见荷载布置断面图。b、采用水准仪测量，分别测量加载前读数。加载时，按照加压荷载的0%、20%、 40%、60%、80%、100%、110%分级进行，加载完成后观测记录，直至最后的平均沉降值<2mm并满足 24 小时以上时方可卸载。然后逐级卸载至100%、80%、60%、40%、20%、0%。待总体沉降量稳定后，最后再测

3、量一次卸载后读数。c、在压载过程中采用水准仪实施全天候跟踪观测挂篮的变形情况并作好记录，待挂篮不再发生沉降，预压过程即告结束。在进行压载施工中，要边进行压载， 边观测挂篮的变形情况，发现异常应立即停止压载作业，及时查找原因，处理正常后再进行压载。d、挂篮标高调整：架体预压前，挂篮按照设计标高调整，通过.预压，观测计算得出挂篮弹性变形数值，调整梁底标高。梁底标高=设计梁底标高 +挂篮弹性变形值 +设计预拱度。挂篮预制块纵面布置图.三、预压过程表 1跨赣江特大桥13#墩挂篮预压记录表序号日期时间施工情况备注12017.10.188:00-8:30加载前22017.10.188:30-9:40加载至

4、 2032017.10.1811:45-14:00加载至 4042017.10.1816:00-17:20加载至 6052017.10.196:30-8:20加载至 8062017.10.1910:20-11:25加载至 10072017.10.1913:00-13:35加载至 11082017.10.2015:35-16:10卸载至 10092017.10.2018:10-18:50卸载至 80102017.10.216:30-7:35卸载至 60112017.10.2110:20-11:25卸载至 40122017.10.2113:00-14:35卸载至 20132017.10.2116:

5、50-18:10卸载至 0.表 2跨赣江特大桥14#墩挂篮预压记录表序号日期时间施工情况备注12017.10.1713:00-13:30加载前22017.10.1716:35-17:20加载至 2032017.10.187:00-7:35加载至 4042017.10.1810:00-10:25加载至 6052017.10.1814:00-14:35加载至 8062017.10.1818:15-18:40加载至 10072017.10.198:35-9:16加载至 11082017.10.209:15-9:45卸载至 10092017.10.2013:00-13:32卸载至 80102017.1

6、0.2017:20-17:50卸载至 60112017.10.219:40-10:06卸载至 40122017.10.2117:31-17:58卸载至 20132017.10.228:10-8:35卸载至 0.四、预压结果汇总表 1预压结果汇总墩 号平均弹性变形13#15 mm14#13 mm五、成果应用本次观测较真实模拟箱梁施工的加载过程 , 达到了预压目的，验证了该挂篮结构的设计满足安全和质量要求。 本次预压所得数据能够指导施工 , 预压结果合格 , 满足规范及设计要求 . 可运用该挂篮进行13#、14#主墩连续梁现浇施工。根据设计图纸，设计只提拱了成桥后预拱度， 在挂篮施工过程中。还要考

7、虑挂篮变形的因素。因此，施工预拱度为挂篮弹性变形值 +设计预拱度，则：对于已预压的挂篮，根据如下公式调整底模标高：底模顶面标高 =梁底设计标高 +设计预拱度（ 1.5cm）+弹性变形即 13#底膜顶面标高 =62.312+0.015+0.015=62.34214#底膜顶面标高 =62.312+0.013+0.015=62.340后附表：预压结果表格.附件 1: 沉降观测点横断面示意图.附件 2: 底版预压观测点平面布置图11755722梁88端（桥13#桥小墩中墩里心程）339946641010图 1 13# 墩底板和上横梁预压观测点平面布置图梁端（大里程）.梁端（小里程）1175572288

8、桥14#桥墩中墩心339946641010图 2 14# 墩底板和上横梁预压观测点平面布置图梁端（大里程）.附件 3: 挂篮沉降监测表表1 跨赣江特大桥 13#墩挂篮预压沉降观测数据记录表布荷载 110序点加荷载 荷载 20荷载 60荷载 80荷载 100卸载 100%卸载卸载 40%卸载弹性形 塑性形号编号位前荷载 40卸载 60%卸载后变（mm）变（mm）0 小时12 小时24 小时80%20%置1161.6719 61.6711 61.659961.651961.647961.641961.638961.637561.637961.639961.6435 61.647661.650961

9、.6545 61.657918142261.6539 61.6530 61.638961.633961.628961.625961.621961.621961.621961.623961.6273 61.630561.634461.6377 61.640917133361.6289 61.6281 61.616961.611961.601961.599961.597961.597661.597961.598961.6021 61.605461.608561.6118 61.614916144461.6019 61.6012 61.587961.579961.575961.573961.5710

10、61.570961.570961.573961.5763 61.578661.581461.5837 61.5859121655大 61.9889 61.9876 61.973961.970961.969961.967961.964561.964561.964561.966961.9685 61.970461.971561.9736 61.9749814里程66端 61.9819 61.9813 61.971961.966961.963961.960961.957561.957661.957661.959961.9619 61.963661.965961.9677 61.96991012777

11、2.6348 72.6336 72.615872.608872.604872.599872.597672.597772.597672.599872.6030 72.606472.609472.6124 72.615816198872.6278 72.6268 72.616872.611872.605872.597672.592572.592872.592572.595872.5996 72.603672.607272.6112 72.614819139972.6088 72.6078 72.595872.592872.588872.583972.580172.580372.580172.581

12、872.5848 72.587572.590872.5936 72.59681512101072.5998 72.5991 72.586872.581872.577872.574672.570372.570372.570372.572872.5756 72.578172.581272.5844 72.58681413.11161.9279 61.9271 61.914961.9099 61.904961.899861.896261.896261.896261.898961.9025 61.906361.909761.9135 61.9169181112261.9389 61.9382 61.9

13、25961.9189 61.914961.912961.908761.908761.908761.910961.9135 61.916161.918761.9214 61.9239131513361.9209 61.9200 61.901961.8959 61.888961.884961.882461.882661.882461.884961.8887 61.892561.896361.9003 61.9039191714461.9179 61.9179 61.901961.8959 61.890961.890961.886561.886761.886561.888961.8919 61.89

14、4561.897961.9009 61.90391514155小 61.9979 61.9968 61.980961.9779 61.975961.972761.968961.968961.968961.970961.9735 61.976361.978761.9815 61.98391314里程166端 61.9889 61.9882 61.976961.9719 61.969961.967561.964861.964661.964761.966961.9687 61.970761.972661.9743 61.975991317772.6428 72.6422 72.627872.6198

15、 72.612872.609672.606472.606472.606472.609872.6136 72.617672.621272.6252 72.6288191418872.6468 72.6460 72.633872.6298 72.621872.613872.610472.610572.610372.612872.6158 72.618672.621872.6246 72.6278151919972.6328 72.6321 72.614872.6088 72.603872.599872.597572.597472.597372.599872.6034 72.607272.61047

16、2.6144 72.61781815201072.6248 72.6240 72.610872.5978 72.592872.589772.581672.586372.586572.588872.5926 72.596672.600672.6042 72.60781917.表 2 跨赣江特大桥14#墩挂篮预压沉降观测数据记录布荷载 110序编号点加荷载 荷载 20荷载 40荷载 60荷载 80荷载 100卸载 100%卸载卸载 60%卸载 40%卸载卸载后弹性形 塑性形号位前80%20%变（mm）变（mm）0 小时12 小时24 小时置1141.28141.27541.27341.27041.

17、27041.26541.26341.26341.26241.26441.27141.27141.27141.27141.272892241.29541.29041.28741.28241.28241.27941.27841.27741.27641.27941.28241.28241.28841.29041.2891063341.29441.28941.28641.28241.28041.27941.27741.27741.27641.27841.27941.28041.28441.28641.2891154441.23841.23541.23241.22641.22441.22241.2214

18、1.22141.22141.22141.22241.22341.22341.22441.2265125541.25841.25441.25141.24741.24441.24441.23541.23441.23441.23541.24241.24241.24341.24341.244914大里41.26241.26041.25841.25441.25241.24641.24641.24541.24641.24641.24241.25241.25441.259131066程 41.269端7751.43551.43151.42751.42351.41951.41251.40851.40751.4

19、0651.40951.41151.41351.41551.41851.42112148851.54751.54251.53751.53151.52751.52151.51851.51751.51751.51851.51951.52051.52251.52551.53113169951.39751.39451.38951.38451.38151.37851.37651.37651.37551.37751.37951.38151.38451.38651.386911101051.62751.62251.61951.61651.61251.61051.60951.60951.60951.60951.

20、61051.61151.61351.61451.615612.11161.38661.38161.37761.37261.36761.36461.36261.36161.36061.36361.36561.36961.37161.37561.37815812261.36161.34861.34761.34561.34361.34261.33961.33861.33761.34061.34161.34361.34561.34761.34991213361.38461.38261.38061.37761.37561.37361.37161.37061.36961.37161.37261.37561.37561.37761.3787614461.41761.41061.40761.40361.39861.39661.39461.39361.39261.39661.39861.40161.40