预应力梁施工方案

预应力梁施工 一、工程概况 程名称:南京鼓楼医院仙林国际医院基本医疗区; 工程地址:仙林大学灵山北路; 建设单位:仙林鼓楼医院投资管理公司; 单位:东南大学设计研究院; 监理单位:理工大学工程兵工程学院南京工程建设监理; 施工单位:江苏南通二建集团有限公司; 建筑面积:104616?;结构在平面上按抗震缝、后浇带、功能区域分为a、b、c、d、e、f、g七个区，其中地上4层，地下1层。 2结构类型:框剪结构，预应力筋截面积A=140mm,波纹管每束8根采S 用Φ80mm，张拉采用一端张拉或两端张拉的方式(分级加荷)张拉端用夹片锚固定端采用挤压锚锚具类型为1类，张拉控制应力 2σ=0.75f=1860N/mm，混凝土强度等级C40。 conptk 整个预应力张拉的施工除按图纸要求施工外，还应满足施工工期，做到先作准备，在规定的时间内完成施工任务。 二、编制依据 1、《混凝土结构设计》(GB50010-2002) 2、《混凝土结构施工及验收规范》(GB50204,2002) 3、《后张预应力混凝土施工手册》 4、《现代预应力混凝土施工》 5、06SG429《后张预应力混凝土结构施工图表示方法及构造详图》 三、原材料的准备 1、钢绞线及锚具的进场 ?预应力钢绞线及锚具应从具有专业资质的优质企业购买，对光面钢 summer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete construction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced bleeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect of concrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective measures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportion of concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the effects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives must be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce the mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in the early days of continuous water conservation to prevent surface drying and covering thin-film wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction preparation 1) required winter construction materials, equipment, planning ahead of time comes into 绞线进场的表面质量要求应逐盘检查，钢绞线捻距应均匀，切散后不松散，其表面不得带有油污，锈斑或机械损伤，但允许有浮锈和回火色。 ?力学性能试验 光面钢绞线采用组批验收规则，由于本工程量小，采用一次进场，一次验收抽检，从钢绞线中任取3盘钢绞线。每盘在任意一端截取一根试件进行拉伸试验，如有某一项试验结果不符合《预应力混凝土用钢绞线》(GB/T5224-2003)标准的要求，则不合格盘报废，再从未试验过的钢绞线中取双倍数量为试件进行复验，如仍有一项不合格，则该批钢绞线判为不合格品。 2、锚具 锚具进场时应有合格证，进场时应按下列验收: ?外观检查 从每批中抽5%~10%的锚具且不少于10套，检查其外观、质量和外形尺寸，其表面应无污物、锈蚀、机械损伤和裂纹，如有一套表面有裂纹，则该批应逐套检查，合格者方可进入后续检验批。 ?硬度检验 对硬度有严格要求的锚具零件，应进行硬度检验，从每批中抽取3%~5%，且不少于3套;按厂家产品设计规定的表面位置和硬度范围作硬度检验。如有一个零件不合格，则应另取双倍数量为零件重做试验，如仍有一件不合格，则判该批产品为不合格品，不逐个检测。 ?静载锚固试验:由生产厂家提供试验报告。 3、波纹管 本工程采用普通金属波纹管，搬运时轻拿轻放，不得抛甩或地上拖拉，吊装时不得使用一根绳索在当中拦腰捆扎起吊，不得长时间裸露在空气中，应采用彩布覆盖保存，接头管采用大一型号的同类波纹管，接头管的长度 250~350mm，接头管两端用密封胶带密封，本工程采用波纹管的加工长度为 4m，便于运输、施工。 YM15,7 采用φ70 接头管:φ75 YM15,8 采用φ70 接头管:φ75 YM15,9 采用φ80 接头管:φ85 YM15,10 采用φ90 接头管:φ95 YM15,12 采用φ90 接头管:φ95 波纹管锚 圈 锚下垫板 螺 旋 筋 序直径 型 号 号 ΦEF A L ΦD ΦGΦHI η (mm) (mm) (mm) (mm) (mm) (mm) (mm) (mm) * YM15-1— — — — — — 1 48 55 80 *YM15-3 2 90 55 135 135 56 160 10 50 4 *YM15-4 3 105 55 150 145 56 190 14 50 5 *YM15-5 4 114 55 165 160 67 210 16 50 5 *YM15-6,7 5 132 60 190 175 77 240 16 60 6 *YM15-8,9 6 158 60 215 215 87 270 16 60 6 *YM15-10-12 7 170 70 250 250 92 320 18 60 7 固定端挤压(P型)锚具结构形式及规格: ials, equipment, planning ahead of time comes intoaration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete con2 固定端挤压(P型)锚具规格系列(mm) 垫 板 螺 旋 筋 序号 型 号 ΦG ΦH A L J I YMP15-4 1 150 240 110 250 190 14 YMP15-5 2 170 300 110 250 210 16 YMP15-6、7 3 200 380 120 250 210 16 YMP15-8 4 210 420 120 250 240 16 YMP15-9、10 5 220 440 120 300 240 16 YMP15-12 6 250 500 135 300 240 16 梁张拉端采用凸出式张拉端。张拉端及固定端均用Φ12,Φ14螺旋筋代替。柱的纵向钢筋为了保证波纹管的正常通过，须作一定的移动，本工程纵向钢筋移动不大。 四、预应力框架梁施工工艺 本工程波纹管位置与预应力筋冲突处，以保证波纹管的位置为主，波纹管接头处是防漏浆和防滑脱的关键，因此采用加密支架稳定波纹管，胶带密封等措施进行加强，为了保证波纹管位置的准确性及牢固性，采用上吊下支并与梁主筋焊牢。 施工工艺流程图如下: 穿钢绞线 1、施工要点: ?预应力楼面梁的支撑系统应与整个波纹管的模板支撑系统单独分开，形成独立支撑系统。 ?预留管道埋设 绑扎构件的普通钢筋时，可同时进行预应力筋管道埋设。采用金属波纹管时，可将金属波纹管按设计的曲线定位在非预应力钢筋笼中。具体的做法是根据矢高沿构件方向每隔约0.8m设置相应的马凳钢筋(根据具体工程情况马凳钢筋间隔可适当调整，保证设计曲线为宜)，马凳钢筋宜采用Φ10~Φ12钢筋，在马凳处用铁丝把波纹管与马凳钢筋绑紧，使波纹管形成曲线。 如图6-1。金属波纹管连接采用比主管大一号的金属波纹管作为连接管，连接管长约200~300mm。在连接管的两端缠上塑料胶带以防漏浆，预埋管道要求曲线流畅，水平顺直。(详见附图1、2、3) 框架梁中预留孔道在竖直方向的净间距不应小于孔道外径;水平方向的净间距不应小于1.5倍孔道外径;从孔壁算起的混凝土保护层厚度，梁底不宜小于50mm，梁侧不宜小于40mm。 aration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete conials, equipment, planning ahead of time comes into4 图6-1 马凳位置示意图 ? 预应力筋穿束 根据工程的具体情况可采用逐根穿束或集束穿束。逐根穿束是将预埋管道内的预应力筋逐根穿入;集束穿束是将管道内所需的预应力筋先绑扎成束后一次性穿入预埋管道内。集束穿束前宜将预应力筋端部用胶布包扎以减小摩擦力并防止穿破波纹管。 人工穿束确有困难，可采用牵引机协助穿束。 ? 端部预埋安装 a 固定端端部预埋安装 固定端采用P型挤压锚时，在保证固定端锚垫板、挤压套筒不外露的前提下，按设计要求的高度固定好预埋件并焊好网片筋或螺旋筋;当采用H型压花锚时也应保证其不外露，同时按设计要求固定好压花端位置。电焊时应注意避免焊条碰到裸露的预应力束。 b 张拉端端部预埋安装 张拉端部有外凸和内凹两种形式。张拉端部预埋位置应符合设计要求，预应力筋应与锚垫板保持垂直。采用外凸式张拉端部时，将锚垫板紧靠构件端部固定;采用内凹式张拉端部时，将锚垫板固定在离端部约90mm处，调整锚垫板周围的钢筋以保证张拉时千斤顶有足够的张拉空间，然后在承压板外安装穴模，按设计要求焊接好网片筋或螺旋筋。采用分段搭接张拉时，张拉端部的预埋安装在锚垫板等预埋件满足设计要求的情况下，预应 力筋与锚垫板应保持垂直，保证张拉千斤顶有足够的张拉空间及张拉完后锚具不露出构件表面。 ? 灌浆管埋设 有粘结预应力的灌浆孔与排气孔(泌水孔)是可通用的。在预应力筋铺设完后进行灌浆管埋设，一般在预埋孔道曲线的高点处留设灌浆管，若是竖向构件，应由孔道底部开始沿高度方向分段埋设。灌浆管间距一般不宜大于12m，在一些较大跨度的构件中，可适当放宽，但管距应能保证灌浆顺畅。灌浆管的压板与金属波纹管应连接牢固，并用塑料胶带缠紧密封以防漏浆。灌浆管高出构件砼表面200~300mm处弯折。为防止灌浆管在浇 ials, equipment, planning ahead of time comes intoaration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete con6 捣混凝土时脱落，可在灌浆管中插入钢筋，将灌浆管与构件的面筋绑紧，同时避免将灌浆管留在构件模板内。 ?钢胶线穿后，严禁电焊、乙炔割刀烧伤钢线和通电。 ?灌浆孔和出气孔的位置处理正确。 ?锚垫板与钢绞线工作时应垂直，以免张拉时断筋。 ?张拉槽(洞)的留置位置严格按设计图纸要求留置，根据留置的部位不同而需要增设的加腋不可遗漏。施工方法参照06SG429图集的P36-38和P58-59页执行。加腋详见附图:加腋示意图 2、隐检及浇筑砼预应力施工人员注意事项 ?预埋完毕后以及钢筋绑扎完毕后，报请甲方、监理单位、设计单位、验收，合格后方可进入下部工序施工即浇筑砼。 ?浇筑砼时预应力施工单位先交底，要求保证孔道不变位，不变形，并派专人24小时看护浇筑过程及时检查孔道、排气孔及压浆孔。管道破损或脱扣，应及时交代及时修补。看护人员监视砼振动棒不得直接接触锚垫板及波纹管，防止损坏波纹管和波纹管移位。 3、预应力张拉及封锚 混凝土强度达到设计要求后可进行张拉(90%)。 预应力张拉由经过专门培训并取得上岗证人员操作，预应力梁的侧模及非预应力楼板的底模(不含梁底模)在张拉前应拆除，采用应力控制伸长值校检的办法，为防止张拉过快，可采用分级加荷的办法即采用:0?0.1σcon(131Mpa)?0.5σcon (655 Mpa)?σcon(1310 Mpa)?1.03σcon(1349 Mpa)持荷3min，持荷3min后即可缓慢卸荷，不得猛回油。张拉控制力不得大于1395 Mpa。 预应力构件的张拉顺序，应根据结构受力特点、施工方便、操作安全等因素确定，一般分楼层、分部位、分段张拉。各楼层部位应遵循对称、均匀原则。 同一束预应力筋，采用相应吨位的千斤顶整束张拉，直线形或扁管内平行排放的预应力筋，当各根预应力筋不受叠压时可采用小型千斤顶逐根张拉。 预应力张拉施工中，质量控制以应力控制为主，测量张拉伸长值作校核。 NLPT预应力筋张拉理论计算伸长值:ΔL= AEPs 式中:N——预应力筋的平均张拉力，取张拉端拉力扣除孔道摩擦损P 失后的拉力平均值; L——预应力筋实际长度 T A——预应力筋截面面积 P E——预应力筋实测弹性模量 s 由多段弯曲线段组成的曲线束，应分段计算，然后叠加，结果较准确。 预应力筋张拉伸长值的量测，在建立预应力后进行，其实际伸长值: ΔL=ΔL+ΔL+ΔL 12C 式中:ΔL——从初应力至最大张拉力之间实测伸长值; 1 ΔL——初应力以下的推算值，可根据弹性范围内张拉力与伸2 长值成正比的关系推算确定; ΔL——施加预应力时，后张法预应力构件的弹性压缩值和固C 定端锚具楔紧引起的预应力筋内缩值，初应力宜为 0.10,0.15σ。 con 张拉预应力筋的理论伸长值与实际伸长值的允许偏差值控制在?6%以内，如超出范围，应查明原因并采取措施予以调整，方可继续张拉。 一次张拉端锚固程序可采用: ials, equipment, planning ahead of time comes intoaration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete con8 0?10%σ?105%σ(持荷2min)?σ?锚固或0?10%σ?conconconcon103%σ?锚固 con 张拉时搞好张拉操作台搭设，清理出最小的张拉空间，确保张拉人员安全施工，同时提供动力电源及照明设施到张拉外，保证压浆所用水接至施工处，同时注意事先停电通知，避免不必要的质安事故，张拉完毕之后停12—24小时后，若无滑丝现象，即可进行孔道压浆，材料要求如下，普硅水泥42.5级，水灰比为0.38—0.4，掺UEA膨胀剂，其掺量由试验室试验后确定，灌浆压力为0.50—0.60MPa，持荷2min，拆模时水泥浆强度为30MPa。 防止孔道漏浆，浇筑后24小时必须清孔。 ?预应力张拉采用分级加荷，张拉采用应力控制、伸长值校核，实际伸长与计算值的允许差应控制在?6%范围内，当伸长值与理论有出入时应分析原因，采取相应措施，方可继续张拉。 ?灌浆采用P.042.5级水泥，水灰比控制在0.4内，掺UEA膨胀剂。 ?灌浆从下向上以上端出浓浆为好，注意留置足够试块，试块强度达30MPa方可拆模。 4、施工控制措施 ?严格施工按施工流水段及操作顺序施工。 ?预应力筋的下料 预应力筋的下料长度应考虑设计曲线长度、张拉端外伸预留长度、弹性回缩值、张拉设备、钢材品种和施工方法等因素，对采用夹片式锚具与穿心式千斤顶进行张拉的构件上的钢绞线，其下料长度L按下式计算: ? 一端张拉时 L=L+L+L+L+L 01234 ? 两端张拉时 L=L+2(L+L+L) 0123 式中:L——构件的孔道长度 0 L——张拉端锚垫板厚度 1 L——夹片式工作锚具厚度 2 L——张拉端外露预留长度 3 L——锚固端长度 4 预应力筋的下料应在平整的场地上直线定出下料长度，并在下料场地两端设置固定标志，每端有专人负责;切断前应将预应力筋拉直;用砂轮切割机切断，不得用电弧切割。在预应力筋下料同时制作装配固定端，当固定端采用P型挤压锚时应采用专用设备对挤压套与锚垫板进行二次挤压以保证挤压套紧固在锚垫板上。对所下的预应力筋做好分区及类型编号，必要时在其两端做出同颜色的标志并标明长度，以便布束张拉时识别，再用放线盘分别盘成直径约为2.0m的圆盘。 预应力筋运至施工现场后要分区、分类堆放。露天堆放时，需覆盖防雨布，并用垫木垫起，不与地面接触，防止锈蚀、死弯。在堆放期间严禁碰撞踩压。 ?钢绞线下料 a、钢绞下料应采用砂轮切割机切割，严禁用电弧切割。 b、钢绞线的编束用20#铁丝绑扎，间距1-1.5m，编束后先将钢绞线理顺，并使各根钢绞线松紧一致。 c、波纹管的组装与钢绞线的穿束与就位。 d、锚垫板组装 穿好束的预应力波纹管就位固定后，即开始组装带喇叭口的锚垫板，应控制好锚垫板的移动，并用胶带密封。 e、成品保护 铺设好的预应力及管道，交叉施工人员应妥善保护不得损坏，施工时严禁在预应力筋上焊，更不能用作电焊导线，现场电焊时应采取隔离措施，防止电弧损伤预应力钢筋。 ials, equipment, planning ahead of time comes intoaration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete con10 f、砼的浇捣 钢筋安装完毕后进行隐检验收，确认无误后方可浇筑砼，砼施工过程中不得使用含氯离子的外加剂，砼试件除应按规定留置验收标准养护试件外，还应留置同等数量的同条件养护试件，张拉施工的依据。砼浇筑时严禁踏压碰撞波纹管、预应力筋、支撑架以及锚垫板。 j、预应力的张拉 ?.张拉前的准备工作 预应力张拉施工前，应检查张拉设备工作情况，保证张拉设备运行良好，并对张拉设备进行标定，所用油压必须通过计量部门标定，张拉机械千斤顶，油表配套在试验机上对输出荷载进行标定，张拉设备的校计强度等级及龄期方可施张，防止徐变现象。 ?.张拉锚的组装 将每个锚垫层板的水泥浆清理干净，并检查锚垫板后的砼密实质量情况，发现问，及时处理，方可装锚。钢绞线按表面粘带泥砂及灰浆用钢刷清除，锚垫板上的灌浆孔内须清洗干净，并畅通。 5、安全注意事项 (1)严格遵守公司及项目的。 (2)张拉操作工只有经过安全教育交底方可上岗。 (3)钢绞线开盘时应注意线头的保护工作，防止钢绞线头弹出伤人。 (4)张拉操作平台必须搭设平稳，有安全网，带保护，不得悬空无保护作业。 (5)张拉过程中，工人应站在千斤顶侧面，严禁千斤顶后站人。 (6)灌浆时，工人应远离灌浆头，防止喷浆伤人。 (7)切割张拉多余钢绞线时，应一根一根切除，禁止两根以上同时切 除，以防砂轮片碎裂。 五、施工质量控制措施 1、材料保证措施 ?严格实行材料进场检验制度，不合格严禁使用。 ?完善技术交底制度，对施工中的技术要点向操作者交底。 ?严把质量关，对每一工序实行“三检”制，并做好“互检”与“交接检”实行层层把关。 ?对材料妥善保护，避免材料破损对产品质量影响。 ?对于张拉机械设备严格校定，保证张拉数据准确无误。 ?对于施工中对质量有关系的工序均由公司有关技术部门直接控制。 ?预先制定好技术方案，保证施工有序、有组织，避免打乱仗忙中出错。 ?为加强预应力施工与其他各工程的协同配合，项目部定期组织技术人员、各工长及各班组负责人参加协调会。 2、施工质量控制标准 ?《混凝土结构工程施工质量验收规范》GB50204-2002中6预应力分项工程的全部控制项目和规定。 ?预应力筋及管道的埋设:管道偏差尺寸误差控制，长度方向?10mm高度方向误差?5mm，锚垫板尺寸误差为?5mm。 ?预应力筋及孔道采用井字架固定，每隔300~500?一道，锚垫板与波纹管垂直，波纹管接头采用胶带纸密封，保证接缝处严密不漏浆。 ?砼浇筑时，振捣时必须派专人看护，不可触及波纹管，防止脱扣漏浆。 ?浇筑混凝土时，振捣器不得触及孔道埋管、预应力筋、撑筋及端部 ials, equipment, planning ahead of time comes intoaration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete con12 节点埋件，梁端混凝土必须振捣密实，严禁出现空洞、蜂窝、麻面。应严格控制混凝土配合比，不宜使用早强剂。 ?预应力梁的侧模及非预应力楼板地模(不含梁底模)应在张拉前全部拆除。施加预应力时，混领土应达到设计强度的100%。 ?除特别注明外，张拉控制预应力均为0.75f,并采用超张拉法减少预ptk 应力损失。要求有粘结筋同一孔应整束同时张拉，不得采用单根张拉法。张拉设备在使用前应进行标定，未经标定不的使用。在张拉前应对张拉端的混凝土质量进行检查，合格后方可进行张拉。 ?预应力筋的张拉管理采用应力控制、伸长值校核，实际伸长值与计算值的允许差为?6%，当超过该值时，应查明原因并采取措施后，方可继续张拉，预应力筋的张拉宜对称进行。预应力筋张拉时应逐根填写张拉记录。 ?张拉完毕，有粘结筋的孔道应及时灌浆，孔道灌浆要求密实，水泥浆强度等级为M40，水灰比不大于0.42，搅拌后3h泌水率不大于2%，泌水应在24h内全部被水泥浆体吸收，可掺入适量无腐蚀性的微膨胀剂和减水剂。掺外加剂后，水泥浆水灰比可降为0.35~0.38。水泥浆中氯离子含量不应大于0.06%。在冷天灌浆前，孔道周边的温度应在5?以上，水泥浆的温度在灌浆后至少有5d保持5?以上，灌浆时水泥浆的温度宜为10,25?灌浆前应用压力水冲洗管道，一方面湿润管道，有利于水泥浆的流动;另一方面检查灌浆孔、排气孔是否正常。在灌浆时应注意灌浆压力为0.5,0.7Mpa,如果超过此压力，应停机，查明原因后方可继续灌浆。张拉完毕后，应及时采用C45补偿收缩细石混凝土封锚，最小保护层厚度不小于50mm。 ?有粘结预应力梁底模及支撑拆除条件:孔道灌浆强度达到20Mpa;支撑与该梁上的上部结构能够自承重;连续梁某跨的相邻跨后浇部分施工完 毕，且强度达到设计要求。 六、设备配备 ?前卡式千斤顶:(26T):1台 ?150T千斤顶2台 ?250T千斤项2台 ?压浆机1台 ?切割机(大小型)各2台 ?手拉葫芦:1T 4部 七、安全及环保措施 预应力施工操作人员在用电及机械使用时除应遵守《施工现场临时用电安全技术规范》JGJ80-91及《建筑机械使用安全技术规程》JG533-2001的有关安全规定外，尚应遵循以下安全措施: 1 张拉预应力筋时其周围及两端应有完善的防护措施，并设置明显的警示标志，非作业人员不得进入作业区域; 2 用砂轮切割机切割预应力筋及波纹管时，作业人员应配戴防护眼镜; 3 施工人员在张拉与测量时应在千斤顶两侧操作，严禁在千斤顶后操作与站立; 4 灌浆时应穿防护服并戴上防护镜，灌浆的机械接口应拧紧到位，不得在孔道口喷射方向观察出浆情况; 5 配制封锚用防腐材料时应防止乙二胺等化学物质溅到皮肤，一旦乙二胺等溅到皮肤上，应立即用清水冲洗。 ials, equipment, planning ahead of time comes intoaration 1) required winter construction materfilm wet grass bag to make it moist State in 24 hours. 8.6.3 8.6.3.1 winter construction measures in winter construction prep-rly days of continuous water conservation to prevent surface drying and covering thinthe eahe mixing time and shipping time at high temperatures. D. strengthen the conservation and high temperatures after pouring in be implemented upon approval by the supervising engineer. C. time control suitable for work at night, should seek to reduce tmust fects of concrete under high temperature, but make some performance degradation of concrete, so when you are using additives concrete 2 degrees, the concrete temperature 0.5 degrees. B. with the controlled addition of retarder agent can reduce the ef ion ofmeasures should be taken. 2) main measures taken by a. temperature control the water temperature in your standard mix proportcrete strength, stability, in varying degrees, on mixing processes, perfusion vibration and moisture conservation, effective of conases rapidly, due to temperature difference cracks. B. pouring daytime high temperatures, due to the high temperature effect eeding, fast drying, easy to crack (plastic), high early strength, fast early hydration heat, less cooling, temperature increstruction in summer high temperature impact on concrete a. hardening speed up, vibrating difficulties reduced blsummer of masonry construction, brick requires sufficient moist. 8.6.2.6 you must take the following measures to concrete con14