Benjamin Lepers^a,*, Aditya Putranto^b,c, Martin Umminger^d, Guido Link^a, John Jelonnek^a

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-11, 2014, DOI:10.5098/hmt.5.13

Abstract The use of high power microwaves to perform explosive spalling of surface concrete is a promising technique with applications in the area of concrete facilities decommissioning. The mechanism that creates explosive spalling is an interactive process of the thermal stress from high temperature gradients and the pore pressure generated from the water vaporization. In order to better predict the total stress distribution, the temperature has to be calculated by including the effect of water vaporization and water transport through a porous medium. In this paper, a one dimensional model solving the heat and diffusion equation for liquid and vapor phase… More >

Fabrizio Greco^*, Paolo Lonetti, Arturo Pascuzzo, Giulia Sansone

Structural Durability & Health Monitoring, Vol.17, No.6, pp. 457-483, 2023, DOI:10.32604/sdhm.2023.030075

Abstract This work proposes a numerical investigation on the effects of damage on the structural response of Reinforced Concrete (RC) bridge structures commonly adopted in highway and railway networks. An effective three-dimensional FE-based numerical model is developed to analyze the bridge’s structural response under several damage scenarios, including the effects of moving vehicle loads. In particular, the longitudinal and transversal beams are modeled through solid finite elements, while horizontal slabs are made of shell elements. Damage phenomena are also incorporated in the numerical model according to a smeared approach consistent with Continuum Damage Mechanics (CDM). In such a context, the proposed… More >

Ali Mahamied¹, Amjad A. Yasin¹, Yazan Alzubi^1,*, Jamal Al Adwan¹, Issa Mahamied²

Structural Durability & Health Monitoring, Vol.17, No.6, pp. 501-519, 2023, DOI:10.32604/sdhm.2023.028686

Abstract Nowadays, an extensive number of studies related to the performance of base isolation systems implemented in regular reinforced concrete structures subjected to various types of earthquakes can be found in the literature. On the other hand, investigations regarding the irregular base-isolated reinforced concrete structures’ performance when subjected to pulse-like earthquakes are very scarce. The severity of pulse-like earthquakes emerges from their ability to destabilize the base-isolated structure by remarkably increasing the displacement demands. Thus, this study is intended to investigate the effects of pulse-like earthquake characteristics on the behavior of low-rise irregular base-isolated reinforced concrete structures. Within the study scope,… More >

Yadong Bian¹, Xuan Qiu¹, Jihui Zhao^2,*, Zhong Li², Jiana Ouyang²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 45-58, 2024, DOI:10.32604/fdmp.2023.029299

Abstract In this paper, the durability of cement mortar prepared with a recycled-concrete fine powder (RFP) was examined; including the analysis of a variety of aspects, such as the carbonization, sulfate attack and chloride ion erosion resistance. The results indicate that the influence of RFP on these three aspects is different. The carbonization depth after 30 days and the chloride diffusion coefficient of mortar containing 10% RFP decreased by 13.3% and 28.19%. With a further increase in the RFP content, interconnected pores formed between the RFP particles, leading to an acceleration of the penetration rate of CO₂ and Cl⁻ . When… More > Graphic Abstract

Guiwu Lin, Kaige Liu, Yuliang Chen^*, Yunpeng Ji, Rui Jiang

Journal of Renewable Materials, Vol.11, No.11, pp. 3957-3975, 2023, DOI:10.32604/jrm.2023.028290

Abstract This paper presents an experimental study to explore the compressive properties of fiber recycled aggregate concrete. A total of 75 specimens with the replacement rate of recycled coarse aggregate and fiber type were conducted under a uniaxial compressive test. The failure modes, stress-strain whole curves, peak stress, peak strain, and energy dissipation capacity were systematically observed and revealed. Test results indicate that steel fiber has the best modification effect on energy dissipation capacity and the toughness index of recycled concrete, corresponding to the enhancement of 81.75% and 22.90% on average. The addition of polyvinyl alcohol fiber can effectively improve the… More > Graphic Abstract

Shanqing Shao¹, Aimin Gong¹, Ran Wang¹, Xiaoshuang Chen¹, Jing Xu², Fulai Wang^1,*, Feipeng Liu^2,3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 3007-3019, 2023, DOI:10.32604/fdmp.2023.029545

Abstract The composite exciter and the CaO to Na₂SO₄ dosing ratios are known to have a strong impact on the mechanical strength of fly-ash concrete. In the present study a hybrid approach relying on experiments and a machine-learning technique has been used to tackle this problem. The tests have shown that the optimal admixture of CaO and Na₂SO₄ alone is 8%. The best 3D mechanical strength of fly-ash concrete is achieved at 8% of the compound activator; If the 28-day mechanical strength is considered, then, the best performances are obtained at 4% of the compound activator. Moreover, the 3D mechanical strength… More >

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 >