共查询到19条相似文献，搜索用时 578 毫秒
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边坡加固锚索预应力损失的探讨 总被引：7，自引：0，他引：7
锚索预应力损失问题是关系到锚固工程安全与否的重要因素。通过对相关边坡工程的监测资料分析，探讨预应力锚索加固边坡的机理、锚索预应力损失的影响因素以及锚索预应力的变化规律，并在此基础上提出应力补偿的措施。 相似文献
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锚索的预应力损失是工程界非常关注的问题。本文结合某电站工程锚索的预应力损失情况,对产生预应力损失的原因进行了系统分析,并针对不同原因提出了避免或减少预应力损失的具体措施。 相似文献
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预应力锚索抗滑桩治理在边坡工程中的应用 总被引：1，自引：0，他引：1
本文分析了预应力锚索抗滑桩加固机理和体系的变形特征特点,并且分析了预应力锚索抗滑桩的内力的计算方法。具体结合边坡治理的一个工程应用,体现出显示这种抗滑结构的优越性。 相似文献
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当前使用的自适应阈值、应力强度因子检测方法,没有考虑路面受到不同张拉力影响而出现的结构问题,导致监测裂缝状态结果较为单一。为了解决该问题,提出了预应力分析下的路堑边坡裂缝不间断监测方法。以X298盘县雨格至普古段改造工程路堑边坡为研究对象,根据锚索预应力监测原理,分析路堑边坡预应力锚索工后状态。采用DIX专业数码相机,不间断地监测流程,拍摄路堑边坡裂缝图像。通过分析图像的局部二元模式特征,计算像素差绝对值,对裂缝区域进行分割。利用对角线方向目标像素点的灰度差,提取路堑边坡裂缝特征。构造高斯滤波函数,避免噪声干扰。通过计算水平和垂直直方图的方差,得到不同预应力条件下各种路堑边坡裂缝监测结果。 相似文献
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龙江水电站公路高边坡发生局部滑坡,为了确定滑坡和边坡的性质,进行了现场勘察,采用钻探和大型原位剪切试验等多种试验手段确定岩土体的物理力学性质指标,然后通过极限平衡理论法分析边坡的稳定性,分析结果表明边坡在正常工况下处于稳定状态,但在暴雨和地震工况下安全系数均偏低,边坡经地表水渗入后或地震状态下处于不稳定状态,因此经过多方研究决定采用分片区治理措施,滑坡区采用抗滑桩加预应力锚索的方案,西侧未发生滑坡区采用预应力锚索和边坡中部强腰加固方案,并设计了合理的排水措施. 相似文献
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本文介绍了预应力锚索在西藏102滑坡临时性保通工程滑坡加固处理中的应用,重点介绍了在地形复杂、地层复杂的大型滑坡体中预应力锚索施工工艺,为同类工程提供借鉴。 相似文献
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浅论高等级公路边坡病害及综合治理方法 总被引：2，自引：0，他引：2
严超群 《杨凌职业技术学院学报》2006,5(4):49-51
本文对高等级公路建设中可能遇到的一些边坡病害作了较为全面的论述,比较了边坡综合治理的一些传统方法及其特点,提出三维植被网植草护坡、客土喷播、喷混植草等新型绿化方式和预应力锚索技术,为高等级公路建设安全维护服务。 相似文献
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《石家庄铁路职业技术学院学报》2017,(1)
随着高速公路建设进程的加快,施工过程以及工后的各种安全防灾治理始终是一项重要的内容,尤其是高边坡的相关治理。针对深路堑高边坡的具体治理过程,有必要探析预应力锚索框架在治理边坡中的重要应用思路。结合边坡治理的真实情况,给出适当的治理流程和方式,确保边坡治理的成效性。 相似文献
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预应力锚索与钻孔咬合桩结合的桩锚支护体系能有效的降低排桩间漏水,减少搭设和拆除深基坑内支撑工程成本,拓宽机械工作面,确保工程工期,避免角撑、对撑施工。通过具体工程案例,系统论述了预应力锚索与钻孔咬合桩结合的桩锚支护体系工艺流程、施工要点及其监测方法,为其在工程中的应用提供理论支撑。 相似文献
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The anchor stress extent of a prestress anchor cable project has a direct relation with the project safety and performance. Prestressed tensioning method is a kind of nondestructive testing method, by which a reverse stretching load is applied on the external exposure section of anchor cable under construction or in service, and then the elongation variation of stress bars is measured to determine the anchor stress. We elaborated the theory and testing mechanism of prestressed tensioning method, and systematically studied key issues during the prestressed tensioning process of anchor cable by using physical model test, including the composition of tension stress-elongation curve, the variation of anchor stress, the compensation of locked anchor stress, and the judgment of anchor stress, and verified the theory feasibility of prestressed tensioning method. A case study on slope anchor cable of one highway project was conducted to further discuss on the test method, operation procedures and judgment of prestressed tensioning method on obtaining anchor stress, and then the test data of three situations were analyzed. The result provides a theoretical basis and technical base for the application of prestressed tensioning method to the evaluation of construction quality and operation conditions of anchor cable project. 相似文献
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以一根预应力钢筋混凝土梁为例,利用MIDAS/FEA和ANSYS建立有限元模型,MIDAS/FEA模型中的预应力采用桁架单元法和钢筋单元法模拟,ANSYS模型中的预应力采用实体切分法、约束方程法以及节点耦合法模拟。分析结果表明,MIDAS/FEA和ANSYS在预应力作用下的计算结果相近,在静力学领域都能得到较为精确的结果;从建模的难易程度上说,MIDAS/FEA的钢筋单元法最为方便,而ANSYS通常需要运用APDL语言辅助建模,难度相对较大;ANSYS采用节点耦合法模拟预应力时,混凝土实体的网格需要划分较密才能取得较为精确的结果。 相似文献
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A double strut cable dome structural system was presented to improve the mechanical behaviour of a cable dome. This structure has good stability and is convenient to construct. To investigate its construction method and static performance, a structural model with a 6-m diameter was designed. From the nodal equilibrium equation, the calculation formulas for the prestress distribution with self-weight considered were deduced. Two types of construction methods, namely, assembling at high altitude and integral lifting, were adopted in the shape-forming process of the double strut cable dome, monitoring the internal force of the cable-strut components and the structural deformation. According to loading tests under full-span load and half-span load, the static behaviour of the structure was obtained and compared with the results from finite element analysis. Using the formulas deduced in this paper, the actual initial prestress considering self-weight for a double strut cable dome can be obtained accurately. This structure was suitable for tensioning the outer diagonal cables to apply prestress. Combined with the construction method for integral lifting, the difficulty and workload of the construction process can clearly be reduced, making the structure favourable for engineering application. Under an external load, the internal force of the ridge cables and inner diagonal cables decreases and the internal force of the other components increases. The results of the model tests were in good agreement with those of the finite element analysis. 相似文献
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苏州胥江桥为预应力桥梁 ,桥型由预制梁形成连续梁和组合梁 ,本文主要介绍预应力铺束、张拉工艺、灌浆工艺。 相似文献
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喷射混凝土防护边坡是一种提高边坡稳定的表面处理方法。喷射混凝土强度高、适用变形能力强,能充分发挥围岩的自承能力,而且施工速度快,经济上也较合理,具有广泛的适应性和推广性。本文介绍此项技术在陆水枢纽除险加固工程3号副坝下游左岸岸坡治理工程中的应用。 相似文献
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The reinforcement effect of a reconstruction scheme for a steel factory building was investigated using finite element method and dynamic performance test. The workshop concerned is a portal frame structure with four spans and two slope roofs, of which ten columns need cutting for expanding span. The design and reconstruction pro- ject of column-cut supported by joist were introduced, which includes column reinforcement, connection rebuilding between brackets and crane beams, and the changing of rigid joint into hinge joint. The construction scheme was put forward in the light of the characteristics of the reinforcement and reconstruction. Spot test of dynamic performance on the workshop and comparison with theoretical analysis results show that the column-cut supported by joist design is effective and the reconstruction project is successful. 相似文献
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姚梅红 《福建工程学院学报》2016,(6):518-525
通过对不同直径的抗拔灌注桩在不同抗拔荷载、不同裂缝控制等级下的抗裂设计及其纵筋用钢量与造价的对比分析,说明桩纵筋采用普通非预应力钢筋时,因受裂缝宽度的限制,其纵筋拉应力水平明显偏低,桩承受的抗拔力越大,纵筋的应力越小,相比普通钢筋混凝土桩,采用预应力螺纹钢筋的抗拔桩不仅可显著减少用钢量,当抗拔力较高时,还可节省约40%~50%的纵筋造价;同时进一步探讨抗拔桩预应力筋的配置及有效预应力的控制方法。 相似文献
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To obtain the relationship between use of installment tensioning technology and the bearing capacity of prestressed concrete beams, tensile and cyclic loading tests are conducted on five rectangular prestressed concreted specimens. Two types of prestressed tensioning methods are adopted in the tests, one uses installment tensioning technology to tension beams on days 4, 12, and 8, 12, respectively, and the other adopts the conventional method to tension the beam on day 28 only. The age of concrete, number of times tensioned, and the prestress value of early tensioning are considered in tests. Results show that use of installment tensioning technology has no effect on the bending failure pattern of prestressed concrete beams, but it reduces prestress loss and increases crack and yield loads. 相似文献