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粘弹性 2

力学性能 1

时温等效 1

本构模型 1

橡胶 1

流变 1

碳酚醛 1

高水头闸门 1

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基于三参量流变模型的止水橡皮粘弹性研究

刘礼华,熊威,张宏志,张清江

《中国工程科学》 2007年第9卷第8期页码 69-71

摘要：

给出了用三参量流变模型研究止水橡胶粘弹性的基本表达式。结合某高水头闸门止水材料的粘弹性试验，得到了所采用橡胶材料的流变参数，并指出了其蠕变变形和应力松弛变化的规律，为工程设计提供参考依据。

关键词：高水头闸门橡胶粘弹性流变

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Rheological behavior of mixed system of ionic liquid [C

Zimeng HE,Ling YUE,Meng LI,Yazhuo SHANG,Honglai LIU

《化学科学与工程前沿（英文）》 2015年第9卷第2期页码 232-241 doi: 10.1007/s11705-015-1511-9

摘要： We report on the rheological behavior of wormlike micelles constructed by ionic liquid surfactant [C mim]Br (1-octyl-3-methylimidazolium bromide) and anionic surfactant sodium oleate (NaOA) in aqueous solution. The effects of surfactant composition, total surfactant concentration, added salts, and temperature were investigated. The prevailing surfactant effect at lower concentration and the leading cosolvent effect at higher concentration of [C mim]Br may be the main reasons for appearance of well-established maximum in key rheological parameters with variation of surfactant composition and total surfactant concentration. The Cole-Cole plots demonstrate that the systems (total surfactant concentration falls within 0.17–0.35 mol·L and molar ratio 0.33≤ ≤0.50) fit the Maxwell’s mechanical model as linear viscoelastic fluid. The addition of NaBr or sodium salicylate decreases significantly the viscosity and the relaxation time of the wormlike micelle solution but cannot change the value of plateau modulus . The present system has low rheological tolerance to temperature. The increase of temperature decreases the average contour length and viscosity of wormlike micelles and thus strengthens the relaxation progress of diffusion and weakens the relaxation progress of reptation. Increasing the temperature also decreases the value of plateau modulus and shifts the minimum value of the loss modulus to higher frequencies.

关键词： rheological behavior ionic liquid surfactant sodium oleate wormlike micelles viscoelasticity

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Influence of morphology on high-temperature rheological properties of bitumen modified with styrene-butadiene-styrene (SBS) copolymer

《结构与土木工程前沿（英文）》 2021年第15卷第3期页码 806-819 doi: 10.1007/s11709-021-0731-y

摘要： Different microstructures of the same polymer-modified bitumen (PMB) were obtained by subjecting the bitumen modified with styrene-butadiene-styrene (SBS) copolymer to isothermal annealing at various temperatures. The effects of the morphology on the rheological properties of SBS-modified bitumen were investigated within the high-temperature range. The PMB microstructures were quantitatively evaluated using image analysis. A dynamic shear rheometer was used to measure the rheological parameters of the PMB samples and perform the multiple stress creep and recovery (MSCR) test. A quantitative basis could be established on which to discuss the relationship between the PMB morphology and rheology. The image analysis indicated that conditioning by isothermal annealing evidently led to a difference in the microstructure of the samples. Variation of the thermal history is demonstrated to be a practical way to vary the morphology of the PMB with the same raw materials and formulation. Compared with the two-phase morphology, the single-phase microstructure tended to have a narrower linear viscoelastic (LVE) region of the PMB. Within the LVE region, especially at low frequencies, the homogenous PMB can store more energy when experiencing loadings and is more elastic. Outside the LVE region, based on the MSCR test results, the homogenous morphology could assist in reaching a higher percentage of strain recovery after the creep period.

关键词： polymer bitumen microstructure rheology viscoelasticity

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Dynamics of structural systems with various frequency-dependent damping models

Li LI,Yujin HU,Weiming DENG,Lei LÜ,Zhe DING

《机械工程前沿（英文）》 2015年第10卷第1期页码 48-63 doi: 10.1007/s11465-015-0330-5

摘要：

The aim of this paper is to present the dynamic analyses of the system involving various damping models. The assumed frequency-dependent damping forces depend on the past history of motion via convolution integrals over some damping kernel functions. By choosing suitable damping kernel functions of frequency-dependent damping model, it may be derived from the familiar viscoelastic materials. A brief review of literature on the choice of available damping models is presented. Both the mode superposition method and Fourier transform method are developed for calculating the dynamic response of the structural systems with various damping models. It is shown that in the case of non-deficient systems with various damping models, the modal analysis with repeated eigenvalues are very similar to the traditional modal analysis used in undamped or viscously damped systems. Also, based on the pseudo-force approach, we transform the original equations of motion with nonzero initial conditions into an equivalent one with zero initial conditions and therefore present a Fourier transform method for the dynamics of structural systems with various damping models. Finally, some case studies are used to show the application and effectiveness of the derived formulas.

关键词： damping viscoelasticity dynamic analysis mode superposition method Fourier transform method

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新型碳酚醛材料动静态力学性能和本构关系研究

张泰,王肖钧,王志海,郭扬,王元博

《中国工程科学》 2006年第8卷第5期页码 63-68

摘要：

研究了碳纤维增强酚醛复合材料在不同温度下的动静态压缩力学性能，碳酚醛材料不但是应变率敏感材料，也是温度相关材料；提出了一个非线性粘弹性本构方程，通过对实验应力-应变曲线的拟合给出了本构方程的材料参数，讨论了温度对本构方程参数的影响；分析了材料力学行为的时温等效性，给出了不同加载条件下的时温等效曲线。

关键词：碳酚醛力学性能粘弹性本构模型时温等效