Ei Yamamoto^1,*, Yuki Tanifuji², Masaya Nishimoto², Yuki Kawamura²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 17-17, 2021, DOI:10.32604/icces.2021.08434

Abstract Bone tissue is a viscoelastic material which shows time-dependent mechanical manner. Moreover, it is known that bone microdamage is generated by physiological normal mechanical loading in vivo [1-3]. In order to know basic insight into the adverse effects of creep loading on bone strength, in the present study, we focused on the mechanical behavior of cortical bone after nondestructive creep loading at high stress magnitude. Cylindrical specimens were obtained from cortical bone in the longitudinal and tangential direction of bovine femur. We statically applied a compressive stress to the specimens (creep group) for 24 hours. More >

Nan Guo^1,*, Huajing Xiong¹, Mingtao Wu¹, Hongliang Zuo¹, Fengguo Jiang², Xiaofeng Hou³, Dabo Xin¹

Structural Durability & Health Monitoring, Vol.14, No.3, pp. 229-248, 2020, DOI:10.32604/sdhm.2020.09104 - 14 September 2020

Abstract Creep is an important characteristic of bamboo and wood materials under long-term loading. This paper aims to study the long-term bending behaviour of prestressed glulam bamboo-wood beam (GBWB). For this, 14 pre-stressed GBWBs were selected and subjected to a long-term loading test for 60 days. Then, a comparative analysis was performed for the effects of pretension values, the number of pre-stressed wires, and long-term load on the stress variation of the steel wire and the long-term deflection of the beam midspan. The test results showed that with the number of prestressed wires increasing, the total… More >

Haiyang Zhou^1,2, Xiaoyu Wang³, Xiaolong Hao^1,2, Qingwen Wang^1,2,*, Rongxian Ou^1,2,*

Journal of Renewable Materials, Vol.8, No.5, pp. 485-498, 2020, DOI:10.32604/jrm.2020.010263 - 29 April 2020

Abstract The mechanical properties of wood flour/high-density polyethylene composites (WPC) were improved by adding a small amount of nano-SiO₂ to obtain a network-structured WPC with a continuous honeycomb-like nano-SiO₂ network. The wood flour was modified with a fire retardant (a mixture of sodium octabonate and amidine urea phosphate) to improve its fire retardancy. The flexural properties, creep resistance, thermal expansion, and fire retardancy of the WPC were compared to a control (WPC_CTRL) without nano-SiO₂ or fire retardant. The flexural strength and modulus of the WPC containing only 0.55 wt.% nano-SiO₂ were 6.6% and 9.1% higher than the control, respectively, More >

Yang Wei^*, Kunpeng Zhao, Chen Hang, Si Chen, Mingmin Ding

Journal of Renewable Materials, Vol.8, No.3, pp. 251-273, 2020, DOI:10.32604/jrm.2020.08779 - 01 March 2020

Abstract The creep behavior of bamboo due to the complicated influences of environment and stress will lead to a sustained increase in deformation, which serious effects the service performance of structures. To investigate the creep behavior of recombinant bamboo, twenty-four recombinant bamboo specimens were tested under lasting compressive and tensile loads at different load levels. The typical failure modes of recombinant bamboo under a lasting load at a high load level were buckling failure and brittle fracturing due to creep compressive creep and tensile creep development, respectively. At a high load level, the creep deformation of… More >

Yoh-ichi Mototake¹, Hitoshi Izuno², Kenji Nagata^3,4, Masahiko Demura² , Masato Okada^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 129-130, 2019, DOI:10.32604/icces.2019.05389

Abstract The creep deformation process is constructed by complex interactions of multiple factors, and the measurement of creep deformation requires enormous economic costs and a long experimental time, so there is a small amount of measurement data. In such a situation, multiple models are often proposed to explain the same experimental data. The coexistence of multiple models based on different physical assumptions makes it difficult to understand the creep deformation process.
The purpose of this study is to construct a framework to compare and evaluate coexistence models based on measurement data using the Bayesian model selection… More >

Junya Sakurai¹, Junya Inoue^2,3,4, Masahiko Demura^4,*, Yoichi Mototake⁵, Masato Okada^4,5, Masayoshi Yamazaki⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 128-128, 2019, DOI:10.32604/icces.2019.05408

Abstract According to the inherent creep strength concept proposed by Kimura et al., microstructural strengthening effect is expiring after a long-term creep deformation at high temperature. In the region, the solid solution hardening effect becomes dominant so that the rupture time is expected to be a simple function of chemical composition and test conditions. In fact, they found that there was a linear relationship between logarithm rupture time and the amount of Mo for the carbon steel JIS STB410. They also found the positive correlations of Cr and Mn to the logarithmic rupture time. However, it… More >

Masahiko Demura^1,*, Junya Sakurai^1,2, Masayoshi Yamazaki¹, Junya Inoue^1,2

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 123-123, 2019, DOI:10.32604/icces.2019.05303

Abstract Creep is a complicated and time-dependent phenomenon, which is affected by the initial state and the degradation of microstructures. It is thus considered that the information about the microstructure is essential to predict the creep rupture time. On the other hand, there is a strong, practical need for the prediction without the investigation of microstructures nor the disclosure of the detailed process that should control the initial microstructures. In this study, we examined how modern machine learning technique can help to predict the creep rupture time in heat-resistant ferrite-type steels without the direct information about… More >

Hitoshi Izuno¹, Masahiko Demura^1,*, Masaaki Tabuchi², Yohichi Mototake³, Masato Okada^1,3

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.2, pp. 121-121, 2019, DOI:10.32604/icces.2019.05270

Abstract An accurate creep deformation model is needed for detailed description of creep behavior of high temperature structural materials, e.g., Grade 91 steels used in boiler tubes of thermal power plants. Two types of creep constitutive equations are known, as follows: the one, e.g., modified theta method, assumes the existence of a steady state; and the other, e.g., theta method, does not. So far, both types have been selected on a case by case basis and there is no consensus on whether or not the steady state should be assumed even if limited in the Grade… More >

Xianglong Su^*, Wenxiang Xu, Wen Chen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.4, pp. 77-77, 2019, DOI:10.32604/icces.2019.05090

Abstract Creep of concrete can last for decades, which displays the ultra-slow rheological phenomena. As an empirical formula, the logarithmic law is usually used to describe the ultra-slow creep. However, the logarithmic law does not always work well especially for the long-term creep. And its corresponding relaxation response cannot be obtained analytically. It is known that the Mittag-Leffler and the inverse Mittag-Leffler functions are generalized from the exponential and the logarithmic functions, respectively. And the inverse Mittag-Leffler function is much slower and generalized than the logarithmic function. In this paper, we use the non-local structural derivative… More >

Hong Y. Yeh, Huan J. Keh^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.3, pp. 343-366, 2017, DOI:10.3970/cmes.2017.113.361

Abstract The problem of the steady migration of an axially symmetric prolate particle along its axis of revolution coinciding with the centerline of a circular capillary is investigated semi-analytically in the limit of low Reynolds number, where the viscous fluid may slip at the solid surfaces. A method of distribution of spherical singularities along the axis inside the particle is employed to establish the general solution of the fluid velocity satisfying the boundary conditions at the capillary wall and infinity. The slip condition at the particle surface is then satisfied by using a boundary collocation method… More >