《o后张法预应力钢绞线伸长量的计算与现场测量控制预应力钢绞线施工时采用张拉应力和伸长值双控》由会员分享，可在线阅读，更多相关《o后张法预应力钢绞线伸长量的计算与现场测量控制预应力钢绞线施工时采用张拉应力和伸长值双控（10页珍藏版）》请在金锄头文库上搜索。
1、traffic management front line, all police always keep has high of spirit State, Strong impetus to the work carried out. There is insufficient: there is a hard and soft. Degree is not enough attention to party building under the new situation, there is emphasis on the operational light, heavy forms o
2、f light effects of party building issues. Second, the measures are not effective. Grasp party construction innovation is not strong in particular, measures and methods also are used to the old experience, old practices, effectiveness needs to be further strengthened. Third, three lessons fail to adh
3、ere to party organization carried out infrequently. Xiao Zhao station branch of good practice: first, strengthening education. Three Suns education as an opportunity to take the leading top party lectures, seminars, self-study, exchanging experiences and other forms of police leaders at all levels o
4、f the Organization important speech, happening around the Constitution and corruption case, police and party members to seriously record study notes, writing experience, . And attention to micro-party lecture, requires checking, improve yourself, ensure that study results. Second is to strengthen th
5、e leadership responsibilities. Secretary of the party branch as honest first person, conscientiously implement the four person requirements, adhere to important deployment in person, major issues personally important cases, coordination of key links in person, personally supervising the party member
6、s always set strict demands on themselves, play an exemplary role. Three is to strengthen the services for the people. Warm reception all who do the people, reflected in record crowds in every issue, and make the patient explanation, continuously improved service quality. Combination of one village,
7、 one police officer, and organizing the police carefully Mo Pai all unstable factors that may affect stability, resolve contradictions and disputes in a timely manner, and civilian police with daily visits, issuing safety information leaflets, collection site personnel, promoting community harmony.
8、There is insufficient: a rich branch team of party affairs knowledge is not enough, enough familiarity with the procedural terms, to a certain extent, restrict the work carried out. Second, regular ideological education is not enough, the police know timely and accurate enough. Third, meticulous man
9、agement level needs to be improved, regularization of police awareness is not strong enough, daily habit is not conscious. This year yilai, Council is units branch to three strict three real topic education for mainline, to service center, and construction team for focus, insisted thought party and
10、system rule party phase combined, solid implement implementation full strictly rule party requirements, party construction further specification, and members police quality constantly upgrade, and party innovation force constantly strengthening, party service implementation force obviously improved,
11、 made has significantly results. Debriefings of the General Assembly of 3 units in the problems in the party building work in other units also exist to varying degrees and hope that other units through debriefing of the party, learn from experience, to address the issue, extrapolate, careful analysi
12、s of rectification, promoting the sustained and healthy development of the party building. Now, to further strengthen the party construction work of public security organs stressed five points throughout the County. First, ideology, political后张法预应力钢绞线伸长量的计算与现场测量控制预应力钢绞线施工时，采用张拉应力和伸长值双控，实际伸长值与理论伸长值误差
13、不得超过6，后张预应力技术一般用于预制大跨径简支连续梁、简支板结构，各种现浇预应力结构或块体拼装结构。预应力施工是一项技术性很强的工作，预应力筋张拉是预应力砼结构的关键工序，施工质量关系到桥梁的安全和人身安全，因此必须慎重对待。一般现行常接触到的预应力钢材主要：有预应力混凝土用钢绞线、PC光面钢丝、刻痕钢丝、冷拔低碳钢丝、精轧螺纹钢等材料。对于后张法预应力施工时孔道成型方法主要有：金属螺旋管、胶管抽芯、钢管抽芯、充气充水胶管抽芯等方法。本人接触多的是混凝土预应力钢绞线（PCstrand、17公称直径15,24mm，fpk 1860Mpa，270级高强底松弛），成孔方法多采用金属螺旋管成孔，本文
14、就以此两项先决条件进行论述。1 施工准备：1.1 熟悉图纸：拿到施工图纸应先查阅施工说明中关于预应力钢绞线的规格，一般预应力钢束采用ASTMA416-270级低松弛钢绞线，其标准强度为fpk1860Mpa，17公称直径15,24mm，锚下控制力为k=0.75 fpk Mpa。1.2 根据施工方法确定计算参数：预应力管道成孔方法采用金属螺旋管成孔，查下表确定K、取值： 表1孔道成型方式K值值钢绞线带肋钢筋精轧螺纹钢预埋铁皮管道0.0030.350.4抽芯成型管道0.00150.550.6预埋金属螺旋管道0.00150.20.250.5注：摘自公路桥涵施工技术规范（JTJ 041-2000）附录G
15、8根据钢绞线试验结果取得钢绞线实际弹性模量Ep（一般为1.92.04105Mpa）1.3 材料检测：金属螺旋管根据公路桥涵施工技术规范（JTJ 041-2000）附录G7之要求检测；锚具根据公路桥梁预应力钢绞线用YM锚具、连接器规格系列（JT/T 329.1-1997）及公路桥梁预应力钢绞线用锚具、连接器试验方法及检验规则（JT/T 329.2-1997）之要求检测；钢绞线根据预应力混凝土用钢绞线GB/T5224-2003之要求检测2 理论伸长量计算：后张法预应力钢绞线在张拉过程中，主要受到以下两方面的因素影响：一是管道弯曲影响引起的摩擦力，二是管道偏差影响引起的摩擦力；两项因素导致钢绞线张拉时，锚下控制应力沿着管壁向跨中逐渐减小，因而每一段的钢绞线的伸长值也是不相同的。2.1 计算公式：公路桥梁施工技术规范(JTJ 041-2000)中关于预应筋伸长值L的计算按照以下公式（1）：LPpLApEpL各分段预应力筋的理论伸长值（mm）； Pp各分段预应力筋的平均张拉力（N）；L预应力筋的分段长度（mm）；Ap预应力筋的截面面积（mm2）；Ep预应力筋的弹性模量（Mpa）；公路桥梁施工技术规范(JTJ 041-2000)附录G8中规定了Pp的计算公式（2）：PpP（1e（kx）kxP预应力筋张拉端的张拉力，将钢绞线分段计算后，为每分段的起点张拉力，即为前段的终点张拉力（N）；
