Heng Zhang^1,2, Chao Su^2,*, Zhizhong Song¹, Zhenzhong Shen^1,2, Huiguang Lei³

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 813-826, 2024, DOI:10.32604/cmes.2023.030055

Abstract Mathematical physics equations are often utilized to describe physical phenomena in various fields of science and engineering. One such equation is the Fourier equation, which is a commonly used and effective method for evaluating the effectiveness of temperature control measures for mass concrete. One important measure for temperature control in mass concrete is the use of cooling water pipes. However, the mismatch of grids between large-scale concrete models and small-scale cooling pipe models can result in a significant waste of calculation time when using the finite element method. Moreover, the temperature of the water in the cooling pipe needs to… More >

Zhongguo Tang¹, Haijin Zhuo¹, Beian Li¹, Xiaotao Ma², Siyu Zhao², Kai Tong^2,*

Structural Durability & Health Monitoring, Vol.17, No.5, pp. 407-431, 2023, DOI:10.32604/sdhm.2023.026033

Abstract Corrosion can be very harmful to the service life and several properties of reinforced concrete structures. The metal magnetic memory (MMM) method, as a newly developed spontaneous magnetic flux leakage (SMFL) non-destructive testing (NDT) technique, is considered a potentially viable method for detecting corrosion damage in reinforced concrete members. To this end, in this paper, the indoor electrochemical method was employed to accelerate the corrosion of outsourced concrete specimens with different steel bar diameters, and the normal components BB_z and its gradient of the SMFL fields on the specimen surfaces were investigated based on the metal magnetic memory (MMM) method.… More >

Jiaming Zhang¹, Xihua Chu^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.3, pp. 1-2, 2023, DOI:10.32604/icces.2023.09055

Abstract This paper presents a fully coupled hygro-thermo-mechanical bond-based Cosserat peridynamic porous media model for concrete at high temperature [1-3]. The model enables the problem of Poisson's ratio limitation to be relieved and the effect of cement particle size and its independent micro-rotation to be taken into account [4]. A multi-rate explicit integration strategy is proposed, which allows this complex multi-field fully coupled governing equation to be well solved. Numerical simulations mainly focus on the terms of temperature, water vapour pressure and damage level to verify the validity of the model [5-9]. And they additionally demonstrate the effect of cement particle… More >

Wenhu Zhao^1,2,*, Chengbin Du², Xiaocui Chen²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.010048

Abstract Concrete structures such as offshore platforms, costal and port structures, dams, etc., are often submerged in water [1]. The water within concreter pores or cracks has a great influence on crack propagation behavior [2,3]. Several wedge-splitting experiments of compact specimens are conducted with a designed sealing device to study the water effects on concrete crack propagation. Different water pressures and different loading rates are considered loading on the pre-crack surfaces and waterproof strain gauges are stuck along the crack path to observe the fracture process during the experiments. Water pressure values on crack surfaces are recorded by diffused silicon water… More >

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 >