Zhihang Wang^1,*, Jinyu Xu^1,2, Xin Meng¹, Conigjin Zhu¹

Journal of Renewable Materials, Vol.9, No.6, pp. 1157-1168, 2021, DOI:10.32604/jrm.2021.014878

Abstract In this paper, the specimens of polymer-cement composites after 1 d, 7 d, 15 d, and 30 d aging without aging and UV aging are subjected to fixed extension test and tensile test. By observing the mode of the composite in the fixed-elongation test, and measuring the elastic recovery rate, tensile strength, elongation at break, peak tensile strain, tensile toughness and pre-peak tensile toughness of the composite, the effects of UV aging on the bonding and the tensile properties of the composite were studied. And combining with scanning electron microscopy experiments, the micro-mechanism of the effect of ultraviolet aging on… More >

Yinhuan Yang^1,*, Manfeng Gong¹, Xiaoqun Xia¹, Yuling Tang²

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 1239-1249, 2021, DOI:10.32604/cmes.2021.014129

Abstract In order to study the mechanical properties of Z-pins reinforced laminated composite single-lap adhesively bonded joint under un-directional static tensile load, damage failure analysis of the joint was carried out by means of test and numerical simulation. The failure mode and mechanism of the joint were analyzed by tensile failure experiments. According to the experimental results, the joint exhibits mixed failure, and the ultimate failure is Z-pins pulling out of the adherend. In order to study the failure mechanism of the joint, the finite element method is used to predict the failure strength. The numerical results are in good agreement… More >

Meifen Tian^1,#, Bengang Zhang^2,#, Zhigang Wu^1,2,*, Liping Yu^1,*, Lifen Li¹, Xuedong Xi^2,3

Journal of Renewable Materials, Vol.9, No.4, pp. 789-801, 2021, DOI:10.32604/jrm.2021.013844

Abstract Pinus massoniana wood was modified by steam heat-treatment at 160°C, 180°C, 200°C and 220°C respectively and effects of the changes of density, pH, surface wettability and apparent morphology of Pinus massoniana heat-treated wood on its bonding performance were studied in this paper. The results showed that Pinus massoniana wood underwent a series of physical and chemical changes during heat-treatment as the the following: (1) The degradation of hemicellulose and cellulose with low degree of polymerization, degradation and migration of the extract resulting in the decline of density and pH of heat-treated Pinus massoniana wood. (2) Brittle fracture occured on the… More >

Jin Wang¹, Weigang Zhang^2,*, Xiaowei Zhuang^1,*

Journal of Renewable Materials, Vol.9, No.3, pp. 557-568, 2021, DOI:10.32604/jrm.2021.013269

Abstract Using 1–8 years bamboo as materials, the content of different chemical constituent was tested, and the reactive oxygen species (ROS) free radicals produced from laccase treated bamboo were detected by electron spin-resonance (ESR) spectroscope. The wet-process particleboard was made from laccase-treated bamboo by hot pressing and board mechanical properties including internal bond strength (IB), modulus of rupture (MOR) and thickness swelling (TS) after 2-hours water absorption were tested under different conditions. Results showed that laccase mainly catalyze the bamboo components and improved the bonding strength of laccase-treated boards. By ESR measurement on each single component such as milled bamboo lignin,… More >

Boheng Zhu¹, Huaxin Liu^1,*, Genjin Liu², Abasal Hussain², Xiaofei Zhang³, Xuezhi Wang¹

Journal of Renewable Materials, Vol.9, No.3, pp. 507-521, 2021, DOI:10.32604/jrm.2021.013580

Abstract The aim of this study is to improve the bond performance of basalt fiber reinforced polymer (BFRP) bars and recycled aggregate concrete (RAC) after being exposed to high temperatures. The bond behavior (failure modes, bond strength, bond stress-slip curves) between BFRP bars and hybrid fiber recycled aggregate concrete (HFRAC) after being exposed to temperatures ranging from 20°C up to 500°C was studied by using pull-out tests. The effect of high temperatures on mechanical properties of concrete (compressive strength, splitting tensile strength) and tensile strength of BFRP bars was also investigated. The bond strength decreased as the temperature increased and the… More >

Lin Pan, Jinhong Xia, Hongxing Han^*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1219-1228, 2020, DOI:10.32604/fdmp.2020.010545

Abstract In this paper, the discrete element method (DEM) is used to study the microstructure of expansive soils. The results of the numerical calculations are in agreement with the stress-strain triaxial test curve that is obtained for a representative expansive soil. Biaxial compression tests are conducted for different confining pressures (50 kpa, 100 kpa, and 150 kpa). Attention is paid to the following aspects: deviatoric stress, boundary energy, friction energy, bond energy, strain energy, kinetic energy, and the contact force between grains when the test specimen is strained and to the effect of the different confining pressures on the internal crack… More >

Zhen Wang¹, Haitao Li^1,2,*, Rodolfo Lorenzo³, Ileana Corbi⁴, Ottavia Corbi⁴, Changhua Fang²

Journal of Renewable Materials, Vol.8, No.8, pp. 993-1018, 2020, DOI:10.32604/jrm.2020.012488

Abstract Retrofitting of existing ancient and modern timber structures has been an important project recently. And it triggers a need of excellent strengthening methods, so does the strengthening of newly built architecture. Traditional strengthening methods have shortcomings such as high costing and destroying the aesthetic of the structure, many of which can be overcome by means of using fiber reinforced polymer (FRP) composites. However, the behavior of FRP-towood systems has yet to be thoroughly researched compared with their FRP-toconcrete or FRP-to-steel counterparts. As FRP retrofitting and strengthening timber structures has a promising future, better understanding of their failure modes will enable… More >

Yui-Chuin Shiah^{1, *}, Sheng-Chi Huang¹, M. R. Hematiyan²

CMC-Computers, Materials & Continua, Vol.64, No.2, pp. 701-727, 2020, DOI:10.32604/cmc.2020.010417

Abstract In engineering practice, analysis of interfacial thermal stresses in composites is a crucial task for assuring structural integrity when sever environmental temperature changes under operations. In this article, the directly transformed boundary integrals presented previously for treating generally anisotropic thermoelasticity in two-dimension are fully regularized by a semi-analytical approach for modeling thin multi-layers of anisotropic/isotropic composites, subjected to general thermal loads with boundary conditions prescribed. In this process, an additional difficulty, not reported in the literature, arises due to rapid fluctuation of an integrand in the directly transformed boundary integral equation. In conventional analysis, thin adhesives are usually neglected due… More >

Yun Wang¹, Zhen Wang², Lei Zhang^1,*, Minxu Lu¹

Journal of Renewable Materials, Vol.8, No.7, pp. 819-932, 2020, DOI:10.32604/jrm.2020.09395

Abstract The adsorption process of new nicotinic derivatives on Fe (110) surface and diffusion of corrosive particles in inhibition film were studied by quantum chemistry and molecular dynamics simulation, and inhibition mechanism of inhibitor was discussed. The results indicated that the main active sites of three inhibitors are located in N atoms on the five membered ring. The inhibitor YM-1 has the strongest activity of electrophilic reaction, and the adsorption process of inhibitor molecules is polycentric chemisorption. The adsorption energy for inhibitors followed the order of YM-1 > YM-2 > YM-3. The adsorption film YM-1 more effectively impedes the diffusion and… More >

Xiangya Luo, Haiqing Ren, Yong Zhong^*

Journal of Renewable Materials, Vol.8, No.7, pp. 773-787, 2020, DOI:10.32604/jrm.2020.09414

Abstract To further verify the feasibility of newly designed reinforced bamboo scrimber composite (RBSC) beams used in building construction, the bonding properties between steel bar and bamboo scrimber were investigated by anti-pulling tests. Results indicated that the anti-pulling mechanical properties were signifi- cantly correlated to the diameter, thread form and buried depth of steel bar, forming density of bamboo scrimber as well as the heat treatment of bamboo bundle. There were two failure modes for anti-pulling tests: the tensile fracture and pulling out of steel bar. Both the ultimate load and average shear strength of anti-pulling specimen could be increased greatly… More >