高速公路桥墩抗震计算书

高速公路桥墩抗震计算书项目概况XX县至XX高速公路是XX至XX国家高速公路（XX）XX境内路段，XX院承担了该项目第XX合同段的勘察设计工作。路线起于XX县城南五里铺，终点位于XX市XX区XX镇，路线全长81.625km。本项目直接或间接影响区域均为大地震的受灾区。地震动加速度峰值0.30g（抗震设防烈度为Ⅷ度），抗震设防措施等级为9度。地震动反应谱特征周期0.4s。由于本项目地震烈度较高，桥梁抗震计算显得非常重要。计算内容（1）、地震作用本项目大部分桥梁均为20米、30米预制预应力混凝土连续箱梁桥，现选取几种典型结构及墩高组合计算抗震，为本项目桥梁抗震设计提供参考。详细选取类型见下表：孔数（孔）-跨径（米米）墩高组合（米）5X205+8+7+665X2011+20+225+1555X2015+20+225+1555X2020+25+225+2005X2020+25+225+2004X305+7+64X3011+30+2254X3016+30+2254X3020+30+2254X3025+30+225注：墩高组合中“5+7+6”表示1号墩高5米，2号墩高7米，3号墩高6米。以下类推。根据公路桥梁抗震设计细则（JTG/TB02-01-2008），一般情况下，公路桥梁可只考虑水平向地震作用，直线桥可分别考虑顺桥向和横桥向的地震作用。在顺桥向地震作用影响下，由于矮墩相对刚度较大，承担的力也相应较大。因此，高低墩搭配情况下对矮墩更不利；横桥向地震作用下，高低墩搭配情况下对高墩更不利。据此考虑，选取上述几种跨径和墩高组合进行抗震计算。（2）桥梁结构概况跨径：5-20米、4-30米桥梁宽度：12.25米桥梁右偏角：90°墩台结构：柱式台、双柱式桥墩地震烈度：地震动加速度峰值0.30g（抗震设防烈度为Ⅷ度），抗震设防措施等级为9度。支座类型：本项目支座选型见下表上部结

构类型跨径

(m)支座布置位置角度支座型号预制

连续

箱梁20桥台及非连续墩墩处0~45度HDR-D2550-H//8连续墩处0~45度HDR(Ⅲ)--D3500-G100/830桥台及非连续墩墩处0~45度HDR-D3000-H//8连续墩处0~45度HDR(Ⅲ)--D4000-G100/8墩柱配筋率跨径（m）柱径（cm）桩径（cm）直径（mm）根数主筋间距（m）墩柱配筋率ρt桩基配筋率箍筋直径（mmm）箍筋加密间距（cm）箍筋配箍率ρss'2012013025280.1060330.01390.01182Φ1480.01197713015025320.0926880.01480.01111480.00555514015025360.1182770.01360.01181480.00518815017025420.1032220.01460.01141480.0048663014015025380.1182770.01360.01182Φ1680.01356615017025440.1032220.01460.01141480.00486616018025480.1010880.01410.01111480.00457717018025540.0992770.01360.01211480.004311桥梁上下部其他构造详见本项目上下部通用图及桥梁设计细则。桥梁模型地震作用计算依据公路桥梁抗震设计细则（JTG/TB02-01-2008），分别计算E1、E2地震作用下结构内力及位移。计算采用时程分析方法，因本项目暂无地震安全性评价报告，现使用武罐项目地震安全性评价报告中相关曲线。桥梁模型内力、位移采用MIDAS程序计算，按梁格法建模，4-30米跨径模型如下：钻孔资料本次计算采用XX河中典型地质资料，底层情况如下：地层编号地质摩阻力承载力比例系数1圆砾70200500002卵石110400500003强风化粉砂质板板岩16060070000本次计算考虑了桩土作用，采用“m”法确定土弹簧刚度。计算说明抗震计算中需建立减隔震支座和桥墩塑性铰的模型：a、支座模型本项目采用HRD系列高阻尼抗震支座，MIDAS中采用“铅芯橡胶支座隔震装置”类型进行模拟，支座非线性特性值中内容由支座设计单位提供。b、桥墩塑性铰桥墩塑性铰采用集中铰计算，本构关系采用随动硬化模型。在MIDAS中定义桥墩塑性铰特性值之后，将桥墩顶低1倍柱径处设置为塑性铰区域，然后使用MIDAS进行计算。本项目桥墩均为双柱式桥墩，根据公路桥梁抗震设计细则第6.2.2条，计算顺桥向地震作用时桥墩底部为塑性铰区域，计算横桥向地震作用时桥墩顶、底部为塑性铰区域。抗震计算结果E1抗震计算根据公路抗震设计细则，E1地震作用下桥梁结构处于弹性状态，计算采用轴力-弯矩-曲率曲线中的首次屈服弯矩进行控制，若E1地震作用下塑性铰区的弯矩小于首次屈服弯矩即认为桥梁结构处于弹性状态，计算结果见下表：E1顺桥向抗弯验算算孔数（孔）-跨径（米米）墩高组合（米）柱径（米）主筋直径（mmm）主筋根数E1作用下墩底弯矩矩（KN*M）墩柱首次屈服弯弯矩（KN*M）是否满足5X205+8+7+661.225281904.72257满足5X2011+20+225+1551.225281567.72257满足5X2015+20+225+1551.325321506.52938满足5X2020+25+225+2001.425361339.13214满足5X2020+25+225+2001.525421329.73952满足4X305+7+61.425382686.23966满足4X3011+30+2251.425383123.93966满足4X3016+30+2251.525443279.24363满足4X3020+30+2251.625482910.34994满足4X3025+30+2251.725542466.46169满足E1横桥向抗弯验算算孔数（孔）-跨径（米米）墩高组合（米）柱径（米）主筋直径（mmm）主筋根数E1作用下墩底弯矩矩（KN*M）墩柱首次屈服弯弯矩（KN*M）是否满足5X205+8+7+661.22528650.72257满足5X2011+20+225+1551.2252813452257满足5X2015+20+225+1551.325321472.42938满足5X2020+25+225+2001.425361246.33214满足5X2020+25+225+2001.525421433.13952满足4X305+7+61.42538735.93966满足4X3011+30+2251.425382317.23966满足4X3016+30+2251.525441793.14363满足4X3020+30+2251.625481930.24994满足4X3025+30+2251.725542421.96169满足E2抗震计算墩柱计算结果根据公路抗震设计细则，E2地震作用下延性构件（墩柱）可发生损伤，产生弹塑性变形，耗散地震能量，但延性构件（墩柱）的塑性铰区域应具有足够的塑性变形能力。根据公路抗震设计细则第7.3.4条和第7.4.2条分别验算墩柱塑性铰区域斜截面抗剪强度以及塑性铰区域的塑性转动能力。验算结果如下：塑性铰区域斜截面抗剪强度验算根据公路抗震设计细则第6.8条及第7.3.4条计算结果见下表：E2顺桥向地震作用用抗剪验算算孔数（孔）-跨径（米米）墩高组合（米）柱径（米）箍筋直径（mmm）箍筋间距（mmm）塑性铰剪力值（KN）容许剪力值（KKN）是否满足5X205+8+7+661.22Φ1480669.81605.4满足5X2011+20+225+1551.22Φ1480334.91605.4满足5X2015+20+225+1551.31480298.7918.7满足5X2020+25+225+2001.41480249.4998.9满足5X2020+25+225+2001.51480245.91080.4满足4X305+7+61.42Φ16801202.62438.7满足4X3011+30+2251.42Φ1680601.32438.7满足4X3016+30+2251.51480450.81080.4满足4X3020+30+2251.61480389.91163.4满足4X3025+30+2251.71480382.11247.7满足E2横桥向地震作用用抗剪验算算孔数（孔）-跨径（米米）墩高组合（米）柱径（米）箍筋直径（mmm）箍筋间距（mmm）塑性铰剪力值（KN）容许剪力值（KKN）是否满足5X205+8+7+661.22Φ14801339.71605.4满足5X2011+20+225+1551.22Φ1480669.81605.4满足5X2015+20+225+1551.31480597.4423.0满足5X2020+25+225+2001.41480498.7998.9满足5X2020+25+225+2001.51480491.81080.4满足4X305+7+61.42Φ16802405.32438.7满足4X3011+30+2251.42Φ16801202.62438.7满足4X3016+30+2251.51480901.61080.4满足4X3020+30+2251.61480779.91163.4满足4X3025+30+2251.71480764.31247.7满足塑性铰区域的塑性转动能力根据公路抗震设计细则第7.4.2及7.4.3条计算结果见下表：E2顺桥向塑性铰转转角验算孔数（孔）-跨径（米米）墩高组合（米）柱径（米）主筋直径（mmm）主筋根数塑性铰转角值（rad）容许转角值（rrad）是否满足5X205+8+7+661.225280.00160.0181满足5X2011+20+225+1551.225280.00140.0181满足5X2015+20+225+1551.325320.00070.0169满足5X2020+25+225+2001.425360.00020.0176满足5X2020+25+225+2001.525420.00010.0165满足4X305+7+61.425380.00110.0135满足4X3011+30+2251.425380.00210.0135满足4X3016+30+2251.525440.00170.0091满足4X3020+30+2251.625480.00090.0108满足4X3025+30+2251.725540.00020.0096满足E2横桥向塑性铰转转角验算孔数（孔）-跨径（米米）墩高组合（米）柱径（米）主筋直径（mmm）主筋根数塑性铰转角值（rad）容许转角值（rrad）是否满足5X205+8+7+661.225280.00060.0181满足5X2011+20+225+1551.225280.00070.0181满足5X2015+20+225+1551.325320.00030.0169满足5X2020+25+225+2001.425360.00010.0176满足5X2020+25+225+2001.525420.00010.0165满足4X305+7+61.425380.00030.0135满足4X3011+30+2251.425380.00080.0135满足4X3016+30+2251.525440.00030.0091满足4X3020+30+2251.625480.00010.0108满足4X3025+30+2251.725540.00010.0096满足桩基计算结果根据公路抗震设计细则，E2地震作用下桩基础按能力保护原则设计，计算采用轴力-弯矩-曲率曲线中的等效屈服弯矩进行控制，若E2地震作用下桩基础的弯矩小于等效屈服弯矩即认为桩基础处于弹性状态，计算结果见下表：E2顺桥向地震作用用抗弯验算算(桩基)孔数（孔）-跨径（米米）墩高组合（米）桩径（米）主筋直径（mmm）主筋根数E2作用下墩底弯矩矩（KN*M）墩柱首次屈服弯弯矩（KN*M）是否满足5X205+8+7+661.3252842484520满足5X2011+20+225+1551.3252850986692满足5X2015+20+225+1551.5253253036692满足5X2020+25+225+2001.5253647926916满足5X2020+25+225+2001.7254247268977满足4X305+7+61.5253880498054满足4X3011+30+2251.525381028110600满足4X3016+30+2251.825441098812700满足4X3020+30+2251.82548991212700满足4X3025+30+2251.82554880013335满足E2横桥向地震作用用抗弯验算算(桩基)孔数（孔）-跨径（米米）墩高组合（米）桩径（米）主筋直径（mmm）主筋根数E2作用下墩底弯矩矩（KN*M）墩柱首次屈服弯弯矩（KN*M）是否满足5X205+8+7+661.3252833844520满足5X2011+20+225+1551.3252816394520满足5X2015+20+225+1551.5253219916692满足5X2020+25+225+2001.5253625546916满足5X2020+25+225+2001.7254232018977满足4X305+7+61.5253842098054满足4X3011+30+2251.5253825418054满足4X3016+30+2251.72544364510600满足4X3020+30+2251.82548370012700满足4X3025+30+2251.82554481713335满