Liang Wen^1,2,*, Changhong Yan³, Yehui Shi⁴, Zhenxiang Wang⁴, Gang Liu⁴, Wei Shi⁴

Journal of Renewable Materials, Vol.11, No.10, pp. 3681-3692, 2023, DOI:10.32604/jrm.2023.027671

Abstract The treatment of wheat straw is very difficult, and its utilization rate is very low; accumulation causes air pollution and even fire. To make full use of wheat straw resources, we examined how using different physical and chemical methods to treat the wheat straw which can improve its strength abilities, or enhance the activity of wheat straw ash. In terms of concrete additives, it can reduce the amount of cement used. In this paper, we found that alkali treatment can significantly improve the tensile strength of wheat straw fiber, but polyvinyl alcohol treatment has no obvious effect on the strength… More > Graphic Abstract

Ruyi Luo, Yanyan Hu^*, Tingshu He^*, Xiaodong Ma, Yongdong Xu

Journal of Renewable Materials, Vol.11, No.9, pp. 3485-3500, 2023, DOI:10.32604/jrm.2023.027592

Abstract The measures of steam curing and early-strengthening agents to promote the precast components to reach the target strength quickly can bring different degrees of damage to the concrete. Based on this, the new nanomaterial CSH-the hydration product of cement effectively solves these measures’ disadvantages, such as excessive energy consumption, thermal stress damage, and the introduction of external ions. In this paper, the effect of CSH on the early strength of precast fly ash concrete components was investigated in terms of setting time, workability, and mechanical properties and analyzed at the microscopic level using hydration temperature, XRD, and SEM. The results… More >

Suyadi Kartorono^*, Herlien Dwiarti Setio, Adang Surahman, Ediansjah Zulkifli

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 195-208, 2023, DOI:10.32604/sdhm.2022.023259

Abstract This paper sums up the determining analysis of the measuring location of T_refl using a thermocouple during the thermography tests. Laboratory temperature distribution testing methods, analysis of value and location of T_refl measurement are explained in this paper. The heat source is two halogen lamps of 500 watts each fitted at a distance of 30–50 cm. Noises appearing during testing of thermography are corrected with measured T_refl value. The results of thermogram correction of corroded concrete surfaces using T_refl values are displayed in this paper too. The concrete surface temperature results of quantitative image processing method are compared to the… More >

Amthal Hakim¹, Wael Slika^1,*, Rawan Machmouchi¹, Adel Elkordi²

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 175-194, 2023, DOI:10.32604/sdhm.2022.023027

Abstract Corrosion of reinforcing steel in concrete elements causes minor to major damage in different aspects. It may lead to spalling of concrete cover, reduction of section’s capacity and can alter the dynamic properties. For the dynamic properties, natural frequency is to be a reliable indicator of structural integrity that can be utilized in non-destructive corrosion assessment. Although the correlation between natural frequency and corrosion damage has been reflected in different experimental programs, few attempts have been made to investigate this relationship in forward modeling and/or structural health monitoring techniques. This can be attributed to the limited available data, the complex… More >

Zhenqing Shi¹, Guomin Sun¹, Jianyong Pang^2,*

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 239-255, 2023, DOI:10.32604/sdhm.2023.022816

Abstract Applying recycled concrete for engineered projects not only protects the ecological environment but also improves the utilization rate of waste concrete to satisfy sustainable development requirements. However, the mechanical properties of recycled concrete are not as good as those of ordinary concrete. To enhance the former’s performance and increase its popularity and application in engineering fields, notable advances have been made by using steel, synthetic, plant, and mineral fiber materials. These materials are added to recycled concrete to improve its mechanical properties. Studies have shown that (1) steel fibers have a distinct reinforcing effect and improve the strength, toughness, and… More >

Yongdong Yan^*, Youdong Si, Chunhua Lu, Keke Wu

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 225-238, 2023, DOI:10.32604/sdhm.2022.022629

Abstract This research aims to investigate the effect of frost damage on chloride transportation mechanism in ordinary and fiber concrete with both theoretical and experimental methods. The proposed theoretical model takes into account the varying damage levels caused by concrete cover depth and freeze-thaw cycles, which are the two primary parameters affecting the expression of the chloride diffusion coefficient. In the experiment, three types of concrete were prepared: ordinary Portland concrete (OPC), polypropylene fiber concrete (PFC), and steel fiber concrete (SFC). These were then immersed in NaCl solution for 120 days after undergoing 10, 25, and 50 freeze-thaw cycles. The damage… More >

Wei Chen^1,*, Wenhao Zhao¹, Yue Liang¹, Frederic Skoczylas²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2417-2430, 2023, DOI:10.32604/fdmp.2023.030028

Abstract The design of an underground nuclear waste disposal requires a full characterization of concrete under various thermo-hydro-mechanical-chemical conditions. This experimental work studied the characterization of coupled thermo-hydro-mechanical effects using concretes made with cement CEM I or CEM V/A (according to European norms). Uniaxial and triaxial compression under 5 MPa confining pressure tests were performed under three different temperatures (T = 20°C, 50°C, and 80°C). The two concretes were dried under relative humidity (RH) to obtain a partially saturated state of approximately 70%. The results showed that the effects of water saturation and confining pressure are more important than that of… More >

Zhiyong Yang¹, Jiacheng Zhang¹, Henglin Xiao^1,2, Zhi Chen^1,*, Tian Bao¹, Yin Liu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2267-2288, 2023, DOI:10.32604/fdmp.2023.028652

Abstract The use of carbon-fiber heating cables (CFHC) to achieve effective melting of snow and ice deposited on roads is a method used worldwide. In this study, tensile and compressive tests have been conducted to analyze the mechanical properties of the CFHC and assess whether the maximum tensile and compressive strengths can meet the pavement design specifications. In order to study the aging produced by multiple cycles of heating and cooling, in particular, the CFHC was repeatedly heated in a cold chamber with an ambient temperature ranging between −20°C and +40°C. Moreover, to evaluate how the strength of the pavement is… More > Graphic Abstract

Xintong Chen, Pinghua Zhu^*, Xiancui Yan, Lei Yang, Huayu Wang

Journal of Renewable Materials, Vol.11, No.6, pp. 2953-2967, 2023, DOI:10.32604/jrm.2023.027140

Abstract With the emphasis on environmental issues, the recycling of waste concrete, even recycled concrete, has become a hot spot in the field of architecture. But the repeated recycling of waste concrete used in harsh environments is still a complex problem. This paper discusses the durability and recyclability of recycled aggregate concrete (RAC) as a prefabricated material in the harsh environment, the effect of high-temperature curing (60°C, 80°C, and 100°C) on the frost resistance of RAC and physical properties of the second generation recycled coarse aggregate (RCA₂) of RAC after 300 freeze-thaw cycles were studied. The frost resistance of RAC was… More >

Rafal A. Hadi^1,*, Suhad M. Abd², Hadee Mohammed Najm³, Shaker Qaidi^4,5,*, Moutaz Mustafa A. Eldirderi⁶, Khaled Mohamed Khedher^7,8

Journal of Renewable Materials, Vol.11, No.6, pp. 2925-2940, 2023, DOI:10.32604/jrm.2023.025558

Abstract Recent years have witnessed an increase in the quantity of waste glass (WG) across the globe. Replacing the fine aggregate with WG is one of the steps toward preserving the natural resources of the environment and creating low-cost concrete. The present study is concerned with replacing fine aggregates with glass powder (GP) at (0%, 15%, 30%, and 50%). It has studied the fresh and hardened properties (compressive strength, tensile strength, hardened density, and slump) for all the mentioned percent replacements. The findings have shown that all mixtures containing GP gave acceptable slump results within the design limits (2–5 cm) according… More >