某水电站引水隧洞衬砌结构计算书

目录1计算总说明111计算目的及要求112基本资料113计算原则和假定114材料参数215参考书目及资料22计算过程321围岩分担内压322按初拟配筋计算钢筋应力823按限裂标准复核钢筋应力924抗外压计算113计算成果及分析134附图13引水隧洞衬砌结构计算书1计算总说明11计算目的及要求本算稿采用高压隧洞的透水衬砌方法（公式法）对某水电站引水隧洞进行内力和配筋计算，为施工详图设计阶段引水隧洞衬砌的施工图绘制提供合理的数据依据。12基本资料引水隧洞布置于XX河左岸，进水口至调压室引水隧洞长全长15541226M，为有压隧洞。引水隧洞建筑物为3级，结构安全级别为级。沿线山体雄厚，设计洞轴线与主要结构面呈较大角度相交，具备基本的地形地质条件，围岩类别以类为主，局部稳定性差，应及时采取支护措施；少部分洞段属类围岩，基本稳定，类围岩不稳定。、1类围岩段，采用马蹄形断面喷锚支护方式，2、类围岩段采用马蹄形或圆形断面（钢筋混凝土衬砌支护方式），本算稿仅针对钢筋混凝土衬砌支护段进行结构计算。围岩分类及参数详见附页互提资料单。13计算原则和假定高压隧洞的结构设计采用了透水衬砌方法进行计算，本工程采用公式法进行计算。公式法考虑变形协调，计算圆形断面在内水压力作用下围岩、混凝土、钢筋的应力和变形，以及混凝土裂缝开展宽度。充水过程初次充水，内水压力达到一定程度后，高压隧洞衬砌体开裂，内水压力以渗透压力，即体积力的形式作用在混凝土衬体和围岩上，使混凝土衬体内、外水压的压差逐渐降低或趋于平衡，从而在钢筋混凝土上产生的应力都较小。衬砌计算原则1）高压隧洞透水衬砌计算要求隧洞埋深满足挪威准则，且在地质围岩较差段外水满足渗流稳定。2）对2、类围岩，可考虑围岩承受70以上内水压力，对类围岩，可考虑围岩承受70以内内水压力。3）高压固结灌浆除了加固围岩外，作用在混凝土衬砌体上的有效预压应力取值为灌浆压力的15。4）混凝土衬砌厚度受放空检修时外水压力控制，配筋受内压和裂缝限制开展宽度（可适当超过03MM）控制。14材料参数1）材料容重钢筋混凝土容重25KN/M32）材料强度参数混凝土强度等级C25；C25混凝土轴心抗压强度设计值119N/MM2CFC25混凝土轴心抗拉强度设计值127N/MM2T3）钢筋钢筋HPB300级270N/MM2YF钢筋HRB335级300N/MM2钢筋HRB400级360N/MM2YF4）钢筋保护层厚50MMC15参考书目及资料某水电站引水发电系统纵剖面图（见附图1）水工隧洞设计规范DL/T51952004中国电力出版社水工建筑物荷载设计规范DL/T50771997中国电力出版社叶冀广蓄电站水工高压隧洞设计施工的若干问题J水力发电学报199823849四川省XX河某水电站引水发电系统水力过渡过程计算与分析研究报告2008032计算过程21围岩分担内压首先根据某水电站引水隧洞不同洞段的围岩地质条件和衬砌支护参数选取计算断面，见表211引水隧洞计算断面参数列表。表211引水隧洞计算断面参数列表断面序号桩号围岩类别灌浆压力（MPA）衬砌厚度（MM）内径（MM）内水压力（M）1引0020引0158065001950392引0158引0340064002350403引0775引0934064002350454引1200引1450074002350505引1730引1820074002350536引2955引2995085002350627引3225引3245084002350648引3245引3268085002250659引3268引33600840023506510引3570引36600840023506811引3830引39000840023507012引3950引41000940023507113引4345引44060940023507414引4410引45000940019507515引4504引478121080019507716引4919引492711080019507817引4927引493711080019507818引4937引514011180019508019引5140引51601180019508020引5160引5250121180019508121引5250引543521140019508222引5435引581221260019508623引5812引620521260019508724引6467引658411260019508725引6584引66211260019508726引6621引772021260019508927引7720引830621380019509228引8934引8976113800195010129引11610引1177020600195013130引11770引12028220600195013431引12028引1212820600195013532引12128磨改0390220600195013633磨改0670引13085220600195013734引13085引13316220400195013835引13434引13596220400195013836引13784引14275220400195014037引14275引14700220600195014038引14700引14920220600195014139引15305引155412262206001950142注内水压力根据四川省金汤河某水电站引水发电系统水力过渡过程计算与分析研究报告中表66输水道沿线主要节点最大压力控制值进行线性插值求得。根据表211选取的计算断面，初拟配筋，同时结合不同计算断面的地质参数分别求出围岩承受的内水压力PR，计算成果表见表212。围岩承受的内水压力PR计算公式及参数说明如下公式见广蓄电站水工高压隧洞设计施工的若干问题（21）012LNL1RSCSRSSRRRRCSRRAEAPRRBE式中PR围岩承受的内水压力，M；P内水压力，M；R衬砌体（混凝土）内半径，M；RS受力钢筋半径，M；RR隧洞开挖半径，M；RO隧洞开挖半径加松动圈深度，M；AS每米管长钢筋配筋面积，M2；ES钢筋弹模，MPA；EC混凝土弹模，C25，MPA；ER1围岩松动区弹模，MPA；ER2围岩非松动区弹模，MPA；U围岩泊松比。表212围岩承担内水压力计算成果表序号衬厚初拟配筋直径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序号衬厚初拟配筋直径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序号衬厚初拟配筋直径PRRSRRROASESECER1ER2UABPRPR/P33065C22221370719520025534900019200000280004900700002800051200138510107434045C22221375619520023532100019200000280004900700002800051200127711008035045C222213813195200235321000192000002800049007000028000512001277111080360425C22221395219521523532100038200000280004900700002800025600070510907837065C22221404019520025534900019200000280004200600003000051200139210307438065C222214085195200255349000192000002800056008000028000512001379105074390625C222214213195225255349000382000002800042006000030000256000805102072注围岩非松动区弹模、泊松比根据围岩岩性和类别按互提资料单中围岩物理力学参数取值，围岩松动区弹模取07倍非松动区弹模。22按初拟配筋计算钢筋应力固结灌浆管口压力作为预压应力作用于混凝土，灌浆管口压力取015倍设计固结灌浆压力。公式及参数说明（22）SRGP（23）SSRAPG灌浆管口压力，MPA；PS钢筋承担内压，MPA。钢筋应力计算成果见表22。表22按初拟配筋计算钢筋应力成果表序号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备注灌浆管口压力取内水压力的02倍；表中PS值为负值，说明钢筋不承担内压，S值为负值，说明钢筋应力为零。钢筋采用HRB335，允许应力S300310/1352222230MPA。从表中计算结果可以看出初拟配筋情况下的钢筋应力都没有达到允许应力，初拟配筋是合适的。23按限裂标准复核钢筋应力公式及参数说明（参照美国混凝土协会ACI提出受拉构件的裂缝计算经验公式）（24）1/3MAX0450SCWFDA式中WMAX混凝土最大裂缝开展宽度，M；FS钢筋应力，MPA；A2DCS，S为钢筋间距，M；DC005/2，为钢筋直径，（钢筋重心至混凝土受拉边缘的距离），M；表23按限裂标准复核钢筋应力成果表序号DCSAFSWMAXMMMM2MPAM10022006102000024415000002200220061020000244000000030022006102000024400000004002200610200002440000000500220061020000244000000060025006302000025080000017002200610200002440000000800250063020000250280000059002200610200002440000000100022006102000024400000001100220061020000244000000012002200610200002440000000130022006102000024400000001400250063020000250000000015002200610200002448400001416002200610200002448900001517002200610200002445700001018002200610200002449100001519002200610200002449200001520002200610200002449200001521002500630167002083000001220025006301670020833000005230025006301670020841000006240025006301670020837000006250025006301670020862000010260025006301670020842000007270025006302000025088000015280022006102000024411500001929002200610200002449800001630002200610200002448500001431002200610200002441270000213200220061020000244860000143300220061020000244870000143400220061020000244000000035002200610200002440000000360022006102000024415000002370022006102000024495000016380022006102000024485000014390022006102000024471000012由表中数据可以看出初拟配筋是合理的，裂缝宽度在允许范围内。24抗外压计算根据计算结果，内水压力不控制衬砌厚度，故足够的衬砌厚度是为了安全施工需要。但外压将控制衬砌厚度，故外水压力加上高压灌浆的残余有效预压应力，将用来验算衬砌的强度。美国等国采用初估混凝土衬砌厚度的经验计算式如下（25）015CTBTC为理论上的混凝土衬体厚度，实际计算时可以不考虑超挖的B0。衬砌结构本身能承担的最大外压（26）221BAQR表24抗外压计算成果表序号内半径A衬厚外径B计算R外压QBPG能承受的外水压估计存在的外水压力MMMMMPAMPAMPAMPAMPA119505027019511928500827702022350402952351192170082090233235040295235119217009208026423504029523511921701020802952350402952351192170112070306235050310235119253012241034723504029523511921701320503782250503002251192600132470349235040295235119217013204038102350402952351192170142040391123504029523511921701420304012235040295235119217014203041132350402952351192170152030431419504025519511924701523204115195080315195119367015352038161950803151951193670163510381719508031519511936701635103