Jiayu Zhang, Zhenyang Li, Xinli Zhang^*

Journal of Renewable Materials, Vol.10, No.11, pp. 2871-2881, 2022, DOI:10.32604/jrm.2022.019373 - 29 June 2022

Abstract Geopolymers are inorganic aluminosilicate materials, which have been a great research interest as a material for sustainable development. However, they possess relatively low toughness properties similar to brittle solids. The limitation may be altered by fiber reinforcement to improve their strength and toughness. This research describes the synthesis of bamboo shaving (BS) reinforced geopolymer composites and the characterization of their mechanical properties. The effect of BS content (0–2 wt. %) on the physical and mechanical properties and microstructure of metakaolin based geopolymer paste were investigated. The workability, setting time, bulk density, apparent porosity, thermal conductivity,… More >

Beifeng Lv, Na Li^*, Haibo Kang, Yanting Wu, Ben Li, Wei Wang

Journal of Renewable Materials, Vol.10, No.10, pp. 2669-2683, 2022, DOI:10.32604/jrm.2022.019418 - 08 June 2022

Abstract In order to study the modification effect of recycled sand on cement reinforced waste slurry (CWS), triaxial test, scanning electron microscope test and X-ray diffraction test were carried out. The mechanical test of recycled sand and cement reinforced waste slurry (RCWS) shows that the deviatoric stress–strain curve of RCWS samples changes from hardening type to softening type with the increase of recycled sand content; the peak stress increases with the increase of recycled sand content; recycled sand can enhance the shear strength of CWS by increasing both cohesion and internal friction angle. The microscopic test More >

Shahril Anuar Bahari¹, Mohd Nazarudin Zakaria¹, Syaiful Osman¹, Falah Abu¹, Mohamad Jani Saad², Reza Hosseinpourpia^3,*

Journal of Renewable Materials, Vol.10, No.10, pp. 2581-2591, 2022, DOI:10.32604/jrm.2022.021313 - 08 June 2022

Abstract This study investigated the mechanical properties and microstructural characteristics of fiberboard composite produced by naturally-bonded Malaysian bamboo fiber (Bambusa vulgaris). The components that obtained through soda pulping of bamboo culms such as fiber and black liquor, were used for the preparation of high-density fibreboard composite at two target densities of 850 and 950 kg/m³. The bamboo fiberboard composite (BFC) were then produced at 200°C and two pressing parameters of 125 and 175 s/mm. The mechanical properties, e.g., flexural strength and internal bonding (IB) of BFC samples were evaluated according to BS EN 310: 1993 and BS EN 319: 1993, More > Graphic Abstract

Chao Liu^1,2,*, Huawei Liu^2,*, Jian Wu¹

Journal of Renewable Materials, Vol.10, No.5, pp. 1397-1414, 2022, DOI:10.32604/jrm.2022.018386 - 22 December 2021

Abstract In this paper, recycled bricks and recycled concrete were applied to prepare eco-friendly recycled mixed powder (RMP) cementitious material, as a supplementary to replace conventional cement for improve the recycling of construction and demolition waste. Based on the effect of cementitious materials on the hydration of silicate cement, the effects of RMP on the workability, mechanical properties and microstructure of recycled mixed powder concrete (RMPC) with the different replacement ratios and the 8:4 and 6:4 mixing ratio of recycled brick powder (RBP) and recycled concrete powder (RCP) were investigated. The results showed that the fluidity… More >

Fang Jin^*, Dong Zhou, Liying Zhu

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 285-302, 2022, DOI:10.32604/fdmp.2022.017593 - 16 December 2021

Abstract The purpose is to study the microstructure and macroscopic fluid-dynamic behavior of soft soil after it has been subjected to a seepage consolidation procedure. First, the microscopic pore structure of soft clay is quantitatively studied by a scanning electron microscope technique. Second, the average contact area rate of soil particles is obtained employing statistical analysis applied to microscopic images of soft soil, and the macroscopic porosity of soft clay is determined through an indoor geotechnical test. Finally, mathematical relationships are introduced by fitting the results of the test. The results show that the unmodified empirical More >

Song Yang¹, Bing Qi¹, Zubin Ai¹, Zhensheng Cao¹, Shiqin He^2,*, Lijun Li³

Journal of Renewable Materials, Vol.10, No.4, pp. 897-908, 2022, DOI:10.32604/jrm.2022.016653 - 02 November 2021

Abstract It has become a research hotspot to explore raw material substitutes of concrete. It is important to research the mechanical properties of self-compacting concrete (SCC) with slag powder (SP) and rubber particle (RP) replacing cement and coarse aggregate, respectively. 12 kinds of composite modified self-compacting concrete (CMSCC) specimens were prepared by using 10%, 20% and 30% SP and 30%, 40%, 50% and 60% RP. The rheological properties, mechanical properties and microstructure of the CMSCC were investigated. Results indicate that the workability, compressive strength, splitting tensile strength and flexural strength of CMSCC prepared by 20% SP… More >

Jiawei Jiang, Yizhou Shen^*, Jie Tao^*, Zhenfeng Jia, Xinyu Xie, Chaojiao Zeng

Journal of Renewable Materials, Vol.10, No.3, pp. 781-797, 2022, DOI:10.32604/jrm.2022.017230 - 28 September 2021

Abstract A new type of microstructure inspired by the cross section of barchan dunes was proposed to reduce windage, which was considered as a passive drag reduction technology in aerospace manufacturing field. Computational fluid dynamics method was carried out to discuss the effect of the microstructure on the skin friction reduction under high velocity flow condition. Different microstructure heights were employed to survey the reduction of drag. The results illustrated that the appearance of microstructure led to a generation of pressure drag in non-smooth model (with microstructures inspired by cross section of barchan dune) in contrast… More > Graphic Abstract

Jian Yang, Xiaoli Li^*, Hui Wang, Kaiqiang Geng

Journal of Renewable Materials, Vol.9, No.12, pp. 2241-2260, 2021, DOI:10.32604/jrm.2021.015565 - 22 June 2021

Abstract In the present study, in order to investigate the effects of fly ash on the structural evolution and strength damage mechanism of Pisha-sandstone cement soil, unconfined compressive strength tests of Pisha-sandstone cement soil with different fly ash content levels and various ages were carried out. The apparent morphology, microstructures, and chemical compositions of the samples were observed and analyzed using ultra-depth three-dimensional microscopy, scanning electron microscopy, and XRD methods. The results revealed that the unconfined compressive strength levels of Pisha-sandstone cement soil samples displayed increasing trends with the increases in fly ash content and age.… More > Graphic Abstract

Xi Chen^1,2, Ying Li^1,2,*, Hualei Bai^1,2, Liyuan Ma^1,2

Journal of Renewable Materials, Vol.9, No.12, pp. 2189-2208, 2021, DOI:10.32604/jrm.2021.015394 - 22 June 2021

Abstract Recycled concrete powder (RCP) is used more and more in cement-based materials, but its influence on the hydration process is still unclear. Therefore, this paper studied the influence of recycled concrete powder (RCP) on the hydration process of cement and provides a theoretical basis for the hydration mechanism of cement composite materials. The hydration heat method was used to systematically analyze the thermal evolution process of cement paste with or without RCP. Hydration products were identified using X-ray diffraction (XRD) and thermal analysis (TG–DSC). The pore structure change of cement pastes was analyzed by mercury… More > Graphic Abstract

Shengquan Zhou¹, Minjie Shi^1,*, Wei Chen¹, Yongfei Zhang¹, Weijian Wang¹, Haojin Zhang¹, Dongwei Li²

Journal of Renewable Materials, Vol.9, No.11, pp. 1941-1957, 2021, DOI:10.32604/jrm.2021.015693 - 04 June 2021

Abstract The characteristics of soil treated with cationic polyacrylamide (CPAM) mass content of 0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1% were investigated through a series of laboratory tests to explore the practical engineering effect of an expansive soil amended with environmental protection material CPAM. The results indicate that with the increasing CPAM content, the liquid limit and plasticity index of soil decrease, the plastic limit increases, and the free swelling ratio and loaded swelling ratio decrease. Besides, the improved soil has less disintegrating property and better water stability. The shear strength increases as the content increases,… More > Graphic Abstract