【《某预应力连续刚构桥钢束预应力损失计算过程案例》2300字】

某预应力连续刚构桥钢束预应力损失计算过程案例目录TOC\o"1-3"\h\u24264某预应力连续刚构桥钢束预应力损失计算过程案例 1151701.1概述 1153271.2钢束预应力损失计算 1195461.2.1钢束预应力损失原理 198941.2.2钢束预应力损失统计表 2277691.3小结 61.1概述预应力钢束在张拉过程中，会有一定的预应力损失，其中包括摩阻损失、温度损失、钢束应力松弛损失、锚具损失和收缩徐变损失。从MIDAS中查询相关表格。1.2钢束预应力损失计算1.2.1钢束预应力损失原理(1)摩阻损失钢束采用后张法张拉时，预应力钢束和管道之间会产生摩阻力，从而导致钢束预应力减小。计算方法按式7-1计算：σl式中：σl1——摩阻预应力损失；σcon——预应力钢束的张拉控制应力；μ——预应力钢束与管道之间的摩差系数；θ——预应力钢束的弯起角之和；k——预应力管道在每米之内与设计位置的偏差系数；x——从计算截面到张拉端的管道长度。(2)锚具损失钢束采用后张法张拉时，锚具会发生变形、钢束的回缩和接缝压缩，从而导致钢束预应力减小。计算方法按式7-2计算：σl式中：σl2——锚具预应力损失；ΔL——钢束回缩、锚具变形和接缝压缩值；L——预应力钢束有效长度；EP——预应力钢束的弹性模量。(3)混凝土弹性收缩损失钢束预应力在混凝土中的作用导致混凝土出现弹性压缩现象，使混凝土出现弹性变形，使钢束预应力损失。计算方法按式7-3计算：σl式中：σl4——混凝土弹性压缩引起的预应力损失；np——预应力钢束与混凝土的弹性模量比；Δσc——后张拉的预应力钢束产生的混凝土正截面压应力；Z——计算的预应力钢束张拉后的预应力钢束根数。(4)预应力钢束应力松弛损失钢束预应力在混凝土中的作用导致混凝土出现弹性压缩现象，使混凝土出现弹性变形，使钢束预应力损失。计算方法按式7-4计算：σl式中：σl5——钢束应力松弛而产生的预应力损失；ζ——预应力钢束松弛系数；σcon——后张法预应力混凝土梁，传力锚固时的预应力钢束应力。1.2.2钢束预应力损失统计表统计顶板钢束、腹板钢束和底板钢束。见表1.2-1、1.2-2、1.2-3。表1.2-1顶板钢束预应力损失表单元位置应力(考虑瞬时损失):A(kN/m^2)弹性变形损失:B(kN/m^2)比值(A+B)/A徐变/收缩损失(kN/m^2)松弛损失(kN/m^2)应力(考虑所有损失)/应力(考虑瞬时损失)端部有效钢束数5I1088119-35239.20.9676-6026.43-13679.80.949515J1124061-36845.50.9672-6896.87-17343.90.945716I1106090-3592.120.9968-8200.89-15881.10.97526J1127310-3836.470.9966-8991.57-18161.80.972527I1112704-5612.70.995-10033.5-16751.30.970937J1138273-5999.470.9947-10472.2-19511.10.968438I1124578-7232.160.9936-11413.5-18124.90.96734续表1.2-18J1145485-7555.690.9934-11560.9-204380.965549I1132164-8509.790.9925-12516.5-19044.70.964659J1149673-8731.620.9924-12429.1-20981.60.9633510I1137911-9592.460.9916-13393.2-19733.70.9625610J1152828-9595.070.9917-13141.3-21383.40.9617611I1141714-10441.50.9908-14105.6-20196.70.9608711J1151129-9711.930.9916-13544-21225.60.9614712I1142679-11122.50.9903-14786-20316.40.9595812J1153969-10461.30.9909-14380.1-21559.90.9598813I1147237-11856.90.9897-15599.5-20829.10.9579913J1154318-11239.40.9903-15204.3-21608.70.9584914I1149213-12599.40.989-16391.1-21051.10.95651014J1156292-12033.90.9896-16042.2-21844.80.95681015I1161301-13353.50.9885-17324-22451.90.95421115J1163399-12791.20.989-16848.7-22691.80.9551116I1163246-14095.20.9879-18080-22686.20.95281216J1161752-135510.9883-17594.8-22514.20.95381217I1160675-14811.80.9872-18833.1-22394.80.95171317J1158797-14451.10.9875-18489.9-22179.20.95241318I1158797-14612.30.9874-18661.5-22179.20.95211318J1156494-136390.9882-17708.9-21915.60.95391319I1156494-136390.9882-17709.1-21915.60.95391319J1155171-13160.70.9886-17085.4-21764.20.9551320I1155171-15676.10.9864-17100.6-21764.20.95281320J1155546-16081.50.9861-17691.6-21805.70.95191321I1155546-16081.50.9861-17691.4-21805.70.95191321J1156183-16909.60.9854-18611.4-21876.60.95041322I1156183-16728.80.9855-18433-21876.60.95071322J1156393-17216.60.9851-18741.8-21899.30.951323I1158683-15963.40.9862-17530.8-22154.70.9521223J1159277-16703.10.9856-17966.2-22222.20.95091224I1156343-154370.9867-16708-21866.10.95331124J1153042-16199.90.986-17121.2-21491.80.95251125I1151312-14910.50.987-15872.2-21288.60.95481025J1143616-15654.30.9863-16160.8-20456.20.95431026I1151843-14326.50.9876-14992.1-21331.90.956926J1144109-15098.60.9868-15305.6-20503.20.9555927I1153426-13745.50.9881-14098.9-215010.9572827J1141616-14513.40.9873-14405.6-20206.90.9578续表1.2-128I1151129-13149.90.9886-13158.4-21225.50.9587728J1141713-13930.40.9878-13604.2-20196.60.9582729I1152827-131690.9886-12326.1-21383.30.9593629J1137910-13071.60.9885-12841.8-19733.60.9599630I1149672-12330.70.9893-11518.6-20981.50.961530J1132163-11828.50.9896-11958.9-19044.60.9622531I1145485-11021.30.9904-10616.1-20431.90.9633431J1124577-10179.80.9909-10790.6-18124.80.9652432I1138273-9115.150.992-9502.63-195170.9665332J1112703-7941.830.9929-9268.6-16751.20.9695333I1127309-6339.220.9944-8001.27-18161.70.9712233J1106089-5066.240.9954-7170.28-158870.9746234I1124060-37691.90.9665-5809.55-17343.90.9459134J1088118-346800.9681-4195.29-13679.70.95171表1.2-2腹板钢束预应力损失表单元位置应力(考虑瞬时损失):A(kN/m^2)弹性变形损失:B(kN/m^2)比值(A+B)/A徐变/收缩损失(kN/m^2)松弛损失(kN/m^2)应力(考虑所有损失)/应力(考虑瞬时损失)端部有效钢束数5I880962.2-30541.80.9653-15159.400.948115J1021214-36226.60.9645-7486.57-7406.250.949916I949076.2-10603.60.9888-11051.2-3703.130.973326J1040876-4971.750.9952-9379.45-9408.690.977227I985971.5-9221.610.9906-11062.9-6272.460.973137J1047283-6992.950.9933-10672.4-101190.973538I1003609-9092.270.9909-11495.6-7589.280.971948J1052579-8145.590.9923-11476.3-10678.90.971249I1018851-9264.120.9909-12030.7-8543.10.970759J1056726-8886.540.9916-12061.8-11111.10.9697510I1029546-9483.50.9908-12458.7-9259.220.9697610J1058392-9262.750.9912-12473.7-11300.40.9688611I1037012-9542.870.9908-12748.3-9686.030.9692711J1056129-9210.690.9913-12676.2-11104.50.9688712I1039221-101860.9902-13293.8-9716.410.9681812J1057604-9874.690.9907-13321.3-11264.10.9674813I1042061-10746.20.9897-13861.7-10012.60.96689续表1.2-213J1059130-10481.60.9901-13934.4-11434.60.9662914I1044814-11235.30.9892-14389.9-10291.20.96561014J1060336-11051.20.9896-14525.5-11572.80.9651015I1047238-11679.20.9888-14960.1-10520.80.96451115J1061248-115960.9891-15119.3-11684.20.96381116I1047834-12169.70.9884-15504.4-10710.50.96341216J1061966-12159.20.9886-15703.8-11775.20.96271217I1051194-12731.80.9879-16141.6-10869.50.96221317J1059125-12789.50.9879-16310.2-11521.40.96161318I1059125-128620.9879-16401.2-11521.40.96151318J1066070-12419.80.9883-15972.8-12169.80.9621319I1066070-12419.80.9883-15973-12169.80.9621319J1063895-12136.90.9886-15583.3-11955.10.96271320I1063895-13775.90.9871-15594.1-11955.10.96121320J1064129-14001.20.9868-15958.8-11983.50.96061321I1064129-14001.20.9868-15958.6-11983.50.96061321J1055810-14309.50.9864-16359-11315.10.96021322I1055810-14211.30.9865-16266.7-11315.10.96041322J1047165-140590.9866-16076.2-10953.90.96081323I1062984-13678.30.9871-15658.2-11866.80.96121223J1050458-13502.70.9871-15439-107220.96221224I1061243-13201.70.9876-15020.8-11683.80.96241124J1047234-13040.90.9875-14843-10520.40.96331125I1060332-12768.20.988-14409.7-11572.40.96351025J1044809-12632.50.9879-14251.4-10290.80.96441026I1059125-12302.50.9884-13792.4-11434.20.9646926J1042057-12159.80.9883-13708.4-10012.20.9656927I1057599-11795.50.9888-13141-11263.70.9658827J1039215-11591.30.9888-13093.9-9715.990.9669828I1056124-11232.50.9894-12419.8-111040.9671728J1037006-10971.40.9894-12485.9-9685.630.968729I1058387-11460.80.9892-11751.6-11299.90.9674629J1029540-10853.20.9895-11794.2-9258.810.969630I1056721-11142.90.9895-11010.1-11110.60.9685530J1018844-10432.40.9898-10882.8-8542.750.9707531I1052575-10418.60.9901-10142.2-10678.40.970343