| 张运良.考虑垫层材料非线性的压力钢管内水压力传递系数[J].水利学报,2014,45(11): |
| 考虑垫层材料非线性的压力钢管内水压力传递系数 |
| Internal water pressure transmission coefficient of steel penstocks considering nonlinearity of yielding layer |
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| DOI： |
| 中文关键词: 压力钢管 垫层 材料非线性 间隙 内水压力传递系数 |
| 英文关键词: steel penstocks yielding layer material nonlinearity gap internal water pressure transmission coefficient |
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| 中文摘要: |
| 水电站压力钢管或蜗壳外敷设的薄垫层，可以定量调节钢板和外围混凝土所分担的内水压力比例。目前，解析推导内压传递系数计算公式时尚未涉及垫层材料的非线性。本文基于多层圆筒理论和垫层的受力特点，尝试推导了考虑垫层材料的压缩非线性，以及垫层、钢管和混凝土之间存在间隙的内水压力传递系数λ 的解析解。结果表明，垫层作为非线性材料，λ 的大小受间隙、作用内水压力、垫层的厚度、残余应变及当前循环加载阶段的应力-应变关系的影响。算例表明，λ 随垫层初始厚度变薄而增大，即垫层越薄，传递的内水压力越大。此外，λ 随循环加-卸载次数的增加而逐渐减小，但当循环次数达到某一数值后，λ 基本不再变化。 |
| 英文摘要: |
| A thin yielding layer， which is installed between steel liners and surrounding concrete of buried penstocks or spiral cases in hydropower stations， can regulate quantitatively the ratio of internal water pressure allocated between the components. At present， the material nonlinearity of the yielding layer has not been considered in deriving and determining analytically the internal water pressure transmission coefficient λ. In this paper， according to the theory of multilayer cylinder and actual loading features of the yielding layer， the analytical formula for calculating λ was derived， where the material compression nonlinearity of the yielding layer and existence of gaps between the components were first considered. The formula shows that λ is influenced by the gap， applied water pressure， and the thickness， residual strain and stress-strain data at the loading stage of the yielding layer. An example shows that λ varies dramatically with the thickness of the yielding layer. The thicker the yielding layer becomes， the bigger λ is. In addition， λ becomes smaller with the cycle number of loading and unloading for the yielding layer. When the
cycle number exceeds a certain value，λ remains unchanged. |
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