共查询到16条相似文献,搜索用时 125 毫秒
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对钢-混凝土连续组合梁的设计方法进行了分析研究,介绍了钢-混凝土连续组合梁与钢筋混凝土连续梁内力重分布的区别,内力分析模型,连续梁弯矩调幅的幅度与塑性分析方法的一些应用条件。并对连续梁的弯矩进行了计算,通过算例发现内力分析方法和截面的类别是紧密关联的。 相似文献
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次弯矩及其对PPC连续梁受力性能的影响 总被引:1,自引:0,他引:1
从次弯矩产生的机理出发,分析了次弯矩对PPC连续梁极限荷载和内力重分布的影响,得出在低配筋的情况下,可不考虑次弯矩的影响;但在高配筋的情况下,所形成的塑性铰转动能力较小,次弯矩不可忽略。在次弯矩对截面不利的情况下,则应充分考虑次弯矩的影响。对于直线配筋的PPC连续梁,次弯矩能提高塑性铰的转动能力,因此,可增大这种PPC连续梁的弯矩调整幅度。 相似文献
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钢筋混凝土连续梁弯矩调幅法的研究 总被引:4,自引:0,他引:4
通过对Ⅱ、Ⅲ级钢筋混凝土连续梁的对比试验,研究了Ⅲ级钢筋混凝土连续梁的弯矩调幅问题,探讨了不同钢筋型号、不同混凝土受压区高度对调幅限值的影响.试验证明;所有Ⅲ级钢筋混凝土连续梁均达到了充分内力重分布且都满足正常使用要求.本文提出了Ⅲ级钢筋混凝土连续梁的调幅限值及其适用条件. 相似文献
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碳纤维加固混凝土连续梁弯矩重分布设计方法 总被引:1,自引:0,他引:1
根据理论分析和参考文献试验结果,碳纤维加固钢筋混凝土连续梁弯矩调幅系数不能参照<钢筋混凝土连续梁和框架考虑内力重分布设计规程>进行计算,在合理简化的基础上,提出了方便工程设计的实用设计方法. 相似文献
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钢筋混凝土连续梁弯矩调幅法的非线性分析方法 总被引:2,自引:1,他引:1
考虑结构塑性内力重分布的方法中,弯矩调幅法概念明确、计算方便,并在工程设计中广泛应用。本文作者详细论述了一种RC连续梁弯矩调幅法的非线性分析方法,并通过Fortran语言编制的相应程序对5根梁的计算模型进行了分析和比较。 相似文献
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为探索内置灌浆圆钢管桁架预应力混凝土连续梁的塑性内力重分布规律,进行了3根无粘结内置灌浆圆钢管桁架预应力混凝土连续梁的受力性能试验和6根模拟梁的非线性数值模拟分析,论述了这类梁设计用和检测评价用的两类承载能力极限状态及试验梁塑性内力重分布情况。试验结果表明,内置灌浆圆钢管桁架预应力混凝土连续梁正截面承载力极限状态应以任一跨出现荷载开始减小,位移急剧增大为标志;这类连续梁塑性内力重分布及弯矩调幅过程集中体现在中支座塑性铰形成的转动过程中;采用条带分层法进行截面的M-非线性分析,基于试验结果和数值分析结果,分别建立了使用阶段和两类承载能力极限状态下无粘结预应力筋应力增量的计算公式,获得了两类承载能力极限状态下中支座两侧的塑性铰区长度实测值,并拟合得到相应等效塑性铰区长度的计算公式,建立了两类承载能力极限状态下的以中支座与跨中控制截面综合配筋指标βo,i、βo,m为自变量和以中支座控制截面相对塑性转角θp为自变量的内力重分布系数Δ的计算公式。 相似文献
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Based on the ultimate limit state analysis, the required moment redistribution to enable full plastic mechanism for continuous composite beams is derived. The composite beams studied are continuous over the internal support and with a uniform section along the beams which are one of the conventional steel structural forms in Chinese construction practice for buildings and medium span bridges. It is illustrated that the required moment redistribution for the beam increases as the ratio of negative to positive moment resistance reduces, but decreases as the span difference, or the difference of load in the two spans increases. A method to assess the available moment redistribution based on the rotation capacity at the notional plastic hinges of a composite beam is developed. The potential moment redistribution in a continuous composite beam is also assessed when the available rotation capacity at the notional hinge fails to satisfy the required capacity capable of a plastic design. For a continuous composite beam to develop full plastic design, the available moment redistribution for the beam should be greater than or at least equal to the moment redistribution required, hence the full moment redistribution from the hogging region to the sagging region in the beam is capable. The derived available moment redistributions agree with the test results and computer simulations, but in a general lower bound of the strength capacity. An example is given and the results are compared with that based on the moment redistribution proposed in the present Chinese design code for steel-concrete composite beams. The present study provide a design approach to assess the load carrying capacity for a continuous composite beam based on the available moment redistribution capable depending on the rotation capacity or the force ratio etc rather than a fixed value of moment redistribution proposed, so that in most cases, an economic design is capable. 相似文献
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本文提出截面曲率延性K1、K2和K3的概念,来描述二类截面局部失稳对连续组合梁内力重分布的影响,采用非线性增量迭代法,分析了36组二跨连续组合梁承受均布荷载时弯矩重分布的情况。研究表明:二类截面连续组合梁的局部失稳,可采用对中间支承处弯矩调幅30%来等效。本文提出的设计方法,可避免复杂的弹塑性稳定计算。 相似文献
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A comparative study of continuous steel-concrete composite beams prestressed with external tendons: Experimental investigation 总被引:2,自引:0,他引:2
A comparative study of prestressed continuous steel-concrete composite beams is carried out based on an experimental investigation. Four full-scale continuous composite beams were tested, among which two were two-span beams and two were three-span beams. One of the two-span beams was a conventional non-prestressed composite beam, and the other was a composite beam prestressed with external tendons in both the positive and negative moment regions. One of the three-span composite beams was non-prestressed, and the other was prestressed only in the negative moment regions with external high-strength tendons. The cracking behaviors, distortional lateral and local buckling as well as the load carrying capacity of the beams were investigated experimentally. Full plasticity was developed at the mid-span section of each beam; however, the maximum moments attained at the internal supports were governed by local buckling, which is related to the slenderness of the composite section. It is found that in hogging moment regions, the ultimate moment resistance of a composite beam prestressed with external tendons is governed by either distortional lateral buckling or local buckling, or an interactive mode composed of distortional lateral and local buckling. The results show that exerting prestressing on a continuous composite beam with external tendons increases the degree of the internal force and moment redistribution in the beam. A design proposal based on moment redistribution to evaluate the load carrying capacity of continuous composite beams with external tendons is proposed. 相似文献
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连续组合梁的局部失稳与弯矩重分布 总被引:3,自引:0,他引:3
研究了负弯矩区截面未完全塑性时出现局部失稳的连续组合梁的稳定。研究结果表明 :对于第三类截面的连续组合梁局部稳定设计 ,中间支座负弯矩可调幅 2 0 % 相似文献