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81.
铁路立交桥涵施工重点为桥涵预制和铁路架空顶进,桥涵顶进是立交桥施工质量控制的最重要的一个环节。桥涵顶进施工采用多种方法,如:一次顶入法、对顶法、解体顶进法、开槽顶入法等,常用施工方法为一次顶入法。顶进施工常见质景通病为后背变形过大终止顶进、滑板下沉断裂、桥涵扎头开裂、线路横移影响行车等,本篇结合工程施工实例,详细阐述了桥涵顶进施工的技术要点,针对常见质量事故,提出了预防及处理的技术措施,实践证明本篇文章所提出的桥涵顶进事故的预防及处理措施切实可行,效果较为显著。 相似文献
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应用Goodman弹性夹层法对双层组合梁弹性阶段变形的理论分析 总被引:6,自引:0,他引:6
将混凝土板与钢梁的接触面模拟成Goodman非线性弹性夹层,用Goodman弹性夹层法分析双层组合梁在弹性工作阶段的滑移及挠度与荷载之间的关系。通过引入边界条件计算出梁在该约束条件下的滑移规律。用有限元软件ANSYS建立2跨双层连续组合梁的空间模型对该方法的准确性进行验证。计算结果表明,当荷载较小时采用解析法和有限元法计算上层混凝土的界面滑移和挠度值非常接近,两者之差小于7%,该解析法对双层梁在弹性阶段的挠度及滑移变形分析是可行的。 相似文献
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This paper is the second of two companion papers concerning the ultimate hull girder strength of container ships subjected to combined hogging moment and bottom local loads. The nonlinear finite element analysis in Part 1 has shown that local bending deformation of a double bottom due to bottom lateral loads significantly decreases the ultimate hogging strength of container ships. In this Part 2, extending Smith's method for pure bending collapse analysis of a ship's hull girder, a simplified method of progressive collapse analysis of ultimate hogging strength of container ships considering bottom local loads is developed. The double bottom is idealized as a plane grillage and the rest part of the cross section as a prismatic beam. An average stress-average strain relationship of plate/stiffened plate elements employed in Smith's method is transformed into an average stress-average plastic strain relationship, and implemented in the conventional beam finite element as a pseudo strain hardening/softening behaviors. The extended Smith's method is validated through a comparison with nonlinear finite element analysis. 相似文献
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文章以双曲拱桥为研究对象,阐述了粘贴钢板法的加固原理、特点、适用范围、设计要求及施工工艺,并结合具体工程实例,探讨了粘贴钢板法的实际加固效果。 相似文献
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[Objective]To simplify the ship modeling process and improve modeling efficiency, this paper proposes a method for rapidly implementing hull model creation based on hull line drawing.[Methods]Using the CATIA platform, this method adopts the component application architecture (CAA) development tool for secondary development. First, by reading the geometry elements and label information of the hull lines in a drawing, the transformation of the offset points from 2D to 3D is realized. On this basis, the creation of the hull lines, stern and bow is completed, and a 3D wireframe model obtained. Finally, the hull 3D modeling is completed in conjunction with the CATIA native surface creation command. The stability and reliability verification of the developed type value extraction and bow generation program is then carried out via application analysis.[Results]The results show that the compiled program can realize the automatic creation of offset points, transverse lines, waterlines, profile lines and other boundary lines except the top line of the wall, and the centerline and tangent lines created by the bow generator are easily modified and simple for users to operate. [Conclusions]The verification results show that the method of a creating hull model using "Generative Shape Design" and "Drafting" with the hull line drawing as the data input is stable, reliable and able to realize rapid hull modeling, giving it certain practical value. © The Author(s) 2022. 相似文献
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