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预应力高强混凝土管桩极限承载力的试验研究 总被引：1，自引：0，他引：1
朱国英 《深圳职业技术学院学报》2003,2(3):18-20
预应力高强混凝土管桩试验研究结果证明：预应力高强混凝土管桩极限端阻力标准值和桩端阻力修正系数取值偏低，管桩的承载力未能得到充分发挥。作对单桩竖向极限承载力计算公式中的设计参数的取值问题进行了探讨，建议在大量试验研究的基础上，对管桩极限端阻力标准值或桩端阻力修正系数取值进行调整。 相似文献
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本文介绍了预应力高强混凝土管桩（PHC）在建筑工程中的适用范围及其优缺点，并着重阐述了PHC管桩承载力的几种计算方法，提出了PHC管桩在超静孔隙水压力的消散和桩周土的固结作用下，单桩承载力在任意时刻的预测。 相似文献
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根据工程经验，分析预应力混凝土管桩工程从设计质量到施工的技术要求，确定单桩承载力，解决施工中出现的技术问题，对南京地区的管桩施工提出自己的观点。 相似文献
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马时冬 《福建工程学院学报》2003,1(1):33-38
主要讨论目前工程实践中遇到的几个岩土工程问题：预应力高强混凝土管桩的桩体上浮问题、塑料排水带的有效打入深度问题和残积土和风化岩的划分及作为桩基持力层时遇到的问题。 相似文献
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张羽 《宁德师专学报(自然科学版)》2008,20(2):177-179
静压预应力管桩应用于建筑工程基础建设日广泛．根据施工监理工作实践与体会,运用相关法规理论,静压预应力管桩施工流程各工序环节的操作要领、常见问题、整改措施、预防办法及规范要求． 相似文献
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在地质情况复杂且岩溶发育的地区，采用预应力砼管桩代替桩基之前，应对预应力砼管桩进行承载力试验，为设计单位提供设计参考资料。本文以大燕河大桥为例，禅述预应力砼管桩承载力试验过程及其应用。 相似文献
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李兴然 《阅读与作文(高中版)》2021,(3)
三和管桩(003037)于2021年2月4日登陆深交所中小板,公司发行价6.38元,首日开盘后不久便涨停,并一直保持到收盘,最终报收于9.19元,涨幅44％.
三和管桩已成为国内规模最大的预应力混凝土管桩生产企业之一.虽然投资者很容易想当然地以为这是一个没有技术含量的行业,但其实恰恰相反,就以三和管桩为例,公司共有95... 相似文献
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冯宜标 《北京工业职业技术学院学报》2011,10(3):4-7
在安徽省淮河漫滩地区,长期采用夯扩桩作为工业与民用建筑的桩基础,但当15m埋深范围内没有桩端持力层时,采用传统的桩基础存在成本高、工期长等问题。介绍了一种新型的桩基础——预应力管桩在该地区的成功应用。通过一个施工实例介绍预应力管桩适应的地层条件、设计步骤和施工质量检验方法等,为今后预应力管桩在该区的大范围推广使用积累了经验。 相似文献
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预应力管桩基础工程的设计质量监理 总被引：1，自引：0，他引：1
预应力管桩基础工程设计质量监理应当重视设计阶段监理，强调设计与施工场地的具体情况相结合。管桩设计质量监理的六个主要环节，即：优化设计方案、确定单桩承载力、设计布桩、选择桩锤、确定“收锤标准”、根据工程地质条件选择合理的管桩施工方法。文章提出了管桩基础的应用范围，对预应力管桩基础的推广、设计和监理等工作都有较高的参考价值。 相似文献
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Dynamic tests of three bonded and two unbonded full-prestressed concrete beams were carried out.The purpose was to seek the relation between prestressing force and natural frequency.Test results indicate that the frequency of prestressed concrete(PSC)beam increases with the increase in prestressing force approximately.The results are different from the dynamic characteristics of isotropic material beam subjected to compressive axial force which were put forward by Clough et al.The reason is that the beams were considered as isotropic,homogeneous,linear elastic material in the traditional analysis method.However,more accurate results are required in the analysis of frequency of PSC beam.The constitutive mode of PSC member is analyzed based on microstructure of concrete in this paper.The orthotropic linear elastic mode is used to analyze the relation between dynamic frequency and prestressing force of concrete beam,at the same time the equivalent stiffness of prestressed tendon relating to the prestressing force is added to the bending deformation stiffness of the beam.The analytical value agrees well with the test result,indicating that the current analysis method in this paper is feasible to full-prestressed concrete beam. 相似文献
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林明生 《闽西职业技术学院学报》2007,9(2):35-37
在龙岩中山广场地下室顶板预应力项目的工程实践中,根据该广场地下室顶板的预应力设计、预应力筋的布置特点,结合施工中的管理以及技术经济分析,说明龙岩中山广场地下室超长顶板采用无粘结预应力技术,设计施工都是成功的,具有显著的社会和经济效益。 相似文献
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Factors such as errors during the fabrication or construction of structural components and errors of calculation assumption or calculation methods, are very likely to cause serious deviation of many strings＇ actual prestressing forces from the designed values during tension structure construction or service period, and further to threaten the safety and reliability of the structure. Aiming at relatively large errors of the prestressing force of strings in a tension structure construction or service period, this paper proposes a new finite element method （FEM）, the ＂tensile force correction calculation method＂. Based on the measured prestressing forces of the strings, this new method applies the structure from the zero prestressing force status approach to the measured prestressing force status for the first phase, and from the measured prestressing force status approach to the designed prestressing force status for the second phase. The construction tensile force correction value for each string can be obtained by multi-iteration with FEM. Using the results of calculation, the strings＇ tensile force correction by group and in batch will be methodic, simple and accurate. This new calculation method can be applied to the prestressed correction construction simulation analysis for tension structures. 相似文献
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为研究FRP(fiber reinforced plastics)加固在役混凝土柱轴压性能的试验方法,采用后张预应力法对混凝土柱施加初始应力,然后采用附加刚性千斤顶加载法进行模拟FRP加固混凝土柱轴压加载试验,得到应力-应变全曲线。研究结果表明,该试验方法能较好地实现FRP加固在役混凝土柱轴心受压试验。 相似文献
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By using ABAQUS/Explicit, the dynamic process of an offshore wind turbine（OWT） stricken by a ship of 5000DWT in the front direction is simulated. The OWT is located on a large-scale prestressing bucket foundation constructed by an integrated installation technique. According to the simulation results, under the ship collision, a cer-tain range of plastic zone appears within a local area of arc transition structure of the bucket foundation, and the con-crete plastic zone is seriously damaged. As the stress level of OWT tower is relatively low, the OWT tower is less af-fected. A great inertial force is generated at the top of the OWT tower as the mass of nacelle and blades is up to 400 t. The displacement of the tower is in the opposite direction of the ship collision at the end of 1 s under the action of iner-tial force. There is only a minor damage in the ship bow. Most of the kinetic energy is transformed into the plastic dissipation and absorbed by the arc transition structure of bucket foundation. 相似文献
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杨根宏 《泰州职业技术学院学报》2010,10(3):68-71
对受腐蚀的多层混凝土框架结构化工厂房进行加固改造,改变其使用功能,改造成为两条生产线的混凝土搅拌楼。重点从设计及施工工艺方面论述受腐蚀混凝土柱、梁、板的加固处理技术,受腐蚀的梁和柱优先采用加大截面法,板采用体外预应力法。 相似文献
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根据内置CFRP圆管的方钢管高强混凝土的特点,通过引入混凝土强度折减系数和等效约束折减系数,将内置CFRP圆管的方钢管高强混凝土等效为内置CFRP圆管的圆钢管高强混凝土。进而,在统一强度理论的基础上,推导出内置CFRP圆管的方钢管高强混凝土轴压构件的强度承载力。通过引入整体稳定系数,推导出内置CFRP圆管的方钢管高强混凝土轴压中长柱的稳定极限承载力公式。将该公式的计算结果与试验结果进行了比较,结果表明该理论公式是正确可行的。理论公式以期能为工程应用提供帮助。 相似文献
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欧智菁俞杰林上顺王金泽 《福建工程学院学报》2019,(6):511-517
以黄桷湾特大桥为工程背景,选取轴压比、梁墩刚度比、系梁布置形式及柱肢混凝土强度等级为设计参数,应用Midas Civil有限元软件构造了20座三跨对称桥梁计算模型。研究E1地震作用下钢管混凝土双肢格构墩连续梁桥主要控制截面参数地震响应,探讨各设计参数对钢管混凝土双肢格构墩连续梁桥抗震性能的影响规律,并对全桥进行优化验证。研究结果表明:轴压比对地震作用下结构内力和位移有一定影响,建议控制在0.15~0.25;梁墩刚度比对结构的抗震性能影响较大,控制在4.08~10.90时结构的内力分布更加合理;核心混凝土的强度在C40~C50时取值较为合理。 相似文献
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预应力混凝土路面设计准则研究 总被引：2，自引：0，他引：2
对混凝土路面板施加预应力,可显著提高其承载能力,因而相同荷载下板厚可减小.预应力改变了路面板的结构形式,可抵抗更大的冲击、振动和超载.本文讨论了设计预应力混凝土路面的要点,提出了预测预应力路面早期、使用阶段及开裂后压应力的设计步骤.必须清楚区分反复荷载和非反复荷载中的变量,同样需要检查预应力路面在超载下开裂后的恢复情况.文末附一个设计实例说明该方法的应用.,With a concrete pavement slab prestressed, its load-carrying capacity can be significantly increased, thus a thinner slab may be used for the same loading. Prestressing modify the structural behavior of the pavement slab and there is a greater resistance to impact, vibration and overloading. This paper discusses the major design considerations necessary in the successful construction of prestressed concrete pavements and presents a design procedure developed to predict the compressive stress due to prestressing in the pavements at early stage, during service and after cracking. Variation in the approach for repetitive and nonrepetitive loads is clearly distinguished. Check on the recovery after cracking for overloading in prestressed pavements is also needed. Finally, a design example is illustrated the application of the approach developed. 相似文献