Jin Yang^1,2, Senye Liu¹, Xingyang He^1,2,*, Ying Su^1,2, Jingyi Zeng², Bohumír Strnadel^1,3

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.9, pp. 2077-2090, 2024, DOI:10.32604/fdmp.2024.050360 - 23 August 2024

Abstract Phosphate tailings are usually used as backfill material in order to recycle tailings resources. This study considers the effect of the mix proportions of clinker-free binders on the fluidity, compressive strength and other key performances of cementitious backfill materials based on phosphate tailings. In particular, three solid wastes, phosphogypsum (PG), semi-aqueous phosphogypsum (HPG) and calcium carbide slag (CS), were selected to activate wet ground granulated blast furnace slag (WGGBS) and three different phosphate tailings backfill materials were prepared. Fluidity, rheology, settling ratio, compressive strength, water resistance and ion leaching behavior of backfill materials were determined.… More > Graphic Abstract

Mohamed Abdel-Mongy¹, Mudassir Iqbal², M. Farag³, Ahmed. M. Yosri^1,*, Fahad Alsharari¹, Saif Eldeen A. S. Yousef⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.1, pp. 525-543, 2024, DOI:10.32604/cmes.2024.052505 - 20 August 2024

Abstract Alkali-activated materials/geopolymer (AAMs), due to their low carbon emission content, have been the focus of recent studies on ecological concrete. In terms of performance, fly ash and slag are preferred materials for precursors for developing a one-part geopolymer. However, determining the optimum content of the input parameters to obtain adequate performance is quite challenging and scarcely reported. Therefore, in this study, machine learning methods such as artificial neural networks (ANN) and gene expression programming (GEP) models were developed using MATLAB and GeneXprotools, respectively, for the prediction of compressive strength under variable input materials and content… More >

Xiangmiao Wan, Yan Tan^*, Xiong Long

Structural Durability & Health Monitoring, Vol.18, No.4, pp. 505-524, 2024, DOI:10.32604/sdhm.2024.049363 - 05 June 2024

Abstract In this study, we assessed the impact of substituting natural fine aggregates with municipal solid waste incineration bottom ash (MSWI-BA) in steel fiber (SF)-reinforced concrete on its compressive properties post high-temperature exposure. The concrete specimens incorporating MSWI-BA as the fine aggregate and SFs for reinforcement underwent uniaxial compression tests after exposure to high temperatures. Through the tests, we investigated the impact of high-temperature exposure on mechanical properties, such as mass loss rate, stress-strain full curve, compressive strength, peak strain, elastic modulus, and so on, over different thermostatic durations. The analysis revealed that with the increasing… More >

Wei Chen^*, Dingdan Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 915-938, 2024, DOI:10.32604/fdmp.2024.046335 - 07 June 2024

Abstract This study focuses on the effect of ultrafine waste glass powder on cement strength, gas permeability and pore structure. Varying contents were considered, with particle sizes ranging from 2 to 20 μm. Moreover, alkali activation was considered to ameliorate the reactivity and cementitious properties, which were assessed by using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and specific surface area pore size distribution analysis. According to the results, without the addition of alkali activators, the performance of glass powder mortar decreases as the amount of glass powder increases, affecting various aspects such as strength… More >

Junjie Zhao, Diyuan Li^*, Jingtai Jiang, Pingkuang Luo

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 275-304, 2024, DOI:10.32604/cmes.2024.046960 - 16 April 2024

Abstract Traditional laboratory tests for measuring rock uniaxial compressive strength (UCS) are tedious and time-consuming. There is a pressing need for more effective methods to determine rock UCS, especially in deep mining environments under high in-situ stress. Thus, this study aims to develop an advanced model for predicting the UCS of rock material in deep mining environments by combining three boosting-based machine learning methods with four optimization algorithms. For this purpose, the Lead-Zinc mine in Southwest China is considered as the case study. Rock density, P-wave velocity, and point load strength index are used as input variables,… More > Graphic Abstract

Wei Chen^*, Wuwen Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 859-872, 2024, DOI:10.32604/fdmp.2023.029310 - 28 March 2024

Abstract River sand is an essential component used as a fine aggregate in mortar and concrete. Due to unrestrained exploitation, river sand resources are gradually being exhausted. This requires alternative solutions. This study deals with the properties of cement mortar containing different levels of manufactured sand (MS) based on quartzite, used to replace river sand. The river sand was replaced at 20%, 40%, 60% and 80% with MS (by weight or volume). The mechanical properties, transfer properties, and microstructure were examined and compared to a control group to study the impact of the replacement level. The More >

Abidhan Bardhan^1,*, Raushan Kumar Singh², Mohammed Alatiyyah³, Sulaiman Abdullah Alateyah^4,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1521-1555, 2024, DOI:10.32604/cmes.2023.044467 - 29 January 2024

Abstract This research proposes a highly effective soft computing paradigm for estimating the compressive strength (CS) of metakaolin-contained cemented materials. The proposed approach is a combination of an enhanced grey wolf optimizer (EGWO) and an extreme learning machine (ELM). EGWO is an augmented form of the classic grey wolf optimizer (GWO). Compared to standard GWO, EGWO has a better hunting mechanism and produces an optimal performance. The EGWO was used to optimize the ELM structure and a hybrid model, ELM-EGWO, was built. To train and validate the proposed ELM-EGWO model, a sum of 361 experimental results… More >

Kolli Ramujee^1,*, Pooja Sadula¹, Golla Madhu², Sandeep Kautish³, Abdulaziz S. Almazyad⁴, Guojiang Xiong⁵, Ali Wagdy Mohamed^6,7,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1455-1486, 2024, DOI:10.32604/cmes.2023.043384 - 29 January 2024

Abstract Geopolymer concrete emerges as a promising avenue for sustainable development and offers an effective solution to environmental problems. Its attributes as a non-toxic, low-carbon, and economical substitute for conventional cement concrete, coupled with its elevated compressive strength and reduced shrinkage properties, position it as a pivotal material for diverse applications spanning from architectural structures to transportation infrastructure. In this context, this study sets out the task of using machine learning (ML) algorithms to increase the accuracy and interpretability of predicting the compressive strength of geopolymer concrete in the civil engineering field. To achieve this goal,… More >

Kunjian Wang¹, Ruibin He¹, Qianhua Liao¹, Kun Xu¹, Wen Wang¹, Kan Chen^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 563-578, 2024, DOI:10.32604/fdmp.2023.030152 - 12 January 2024

Abstract Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials are generally considered more suitable plugging agents than water-based gels because the latter often undergo contamination via formation water, which prevents them from being effective over long times. Hence, in this study, a set of oil-based composite gels based on waste grease and epoxy resin has been developed. These materials have been observed to possess high compressive strength and resistance to the aforementioned contamination, thereby leading to notable increase in plugging success rate. The compressive strength, thickening time, and resistance to formation 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 - 10 August 2023

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… More > Graphic Abstract