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Since the 16th century, Western countries have conducted extensive plant collections in Asia, particularly in China, driven by the need to collect botanical resources and foster academic development. These activities have not only significantly enriched the Western botanical specimen collections but have also had a profound impact on the development of related disciplines such as botany, ecology, and horticulture. During this process, a large number of renowned plant hunters emerged, whose discoveries and contributions are still remembered today. George Forrest (1873–1932) was one of these distinguished plant hunters. From 1904 to 1932, he visited China seven times to collect plants and became famous for the regional distinctiveness of the species he collected. However, due to the lack of systematic collection, organization, and analysis of specimens collected by Forrest, only a few species, such as the species Rhododendron, are well-known among the many species he introduced to the West. Furthermore, the personal collecting characteristics and the characteristic species collected by Forrest are also not clear. This limits a comprehensive understanding of the specimen collection history and impact of Forrest in China. Therefore, systematic organization and analysis of Forrest's plant specimens collected in China are crucial to understanding his impact on botanical classification, Rhododendrons introduction, global horticulture, and plant propagation. This study aims to systematically organize and analyze the plant specimens collected by George Forrest in China to investigate the family, genus, and species composition of the collected specimens and the seven collection expeditions of Forrest in China, as well as the time and altitude of these collections. Furthermore, it seeks to discuss Forrest's scientific contributions to the global spread of plants, the widespread application of the Rhododendron, and his impact on the development of modern gardens, providing a theoretical basis and data reference for related research and professional development. To this end, we extensively consulted important historical literature related to Forrest and systematically collected data from online specimen databases. The conclusions drawn from the available data include 38,603 specimens, with 26,079 collection numbers, belonging to 233 families, 1395 genera, and 5426 species, which account for 48.24%, 32.63%, and 14.17% of the plant families, genera, and species in China, respectively. Rhododendron specimens made up 17.20% of the specimens collected in this study. The collection locations cover three provinces or autonomous regions, 11 prefecture-level cities, and 25 counties. Furthermore, we found that Forrest's collections were concentrated in spring and summer, mainly in high-altitude areas, with 135 species found below 1500 m and 3754 species at 1500 m and above. Rhododendron specimens were mostly found above 3000 m. [ABSTRACT FROM AUTHOR]

In recent years, electrochemical synergistic activation of persulfate (PDS) degradation technology has demonstrated significant potential in wastewater treatment applications. Given the challenges posed by the complex water quality, high COD content, and recalcitrant degradation of dyeing wastewater, this study aimed to evaluate the efficacy of iron/aluminum dual-electrode electrochemical activation of PDS for degrading simulated dyeing wastewater. The results showed that under optimal conditions, utilizing both periodic reversal and direct current electrochemical activation of PDS achieved removal rates of 99.2% and 98.3% for Reactive Black 5 (RB5) and Reactive Red X-3B (RRX-3B), respectively, demonstrating promising removal efficiency. Notably, the removal efficiency of RB5 surpassed that of RRX-3B, suggesting a dependence on initial concentration influencing reaction kinetics. Furthermore, full-spectrum scanning and quenching experiments revealed that RB5 and RRX-3B were primarily degraded through the potent oxidation action of SO4−· and ·OH, with a small number of intermediates present in the solution. Periodic reversal proved effective in mitigating electrode passivation and enhancing electrode longevity. This study provides a highly effective removal method of binary dyes from dyeing wastewater by periodic reversal Fe-Al dual-electrode electrochemical activation of PDS technology, offering valuable insights for sustainable treatment of dyeing wastewater with binary components. [ABSTRACT FROM AUTHOR]

The Fang'an gold deposit in the Wuhe area, Anhui Province, is located in the area adjacent to the Bengbu Uplift and Wuhe Platform Depression in the southeastern part of North China. This study aimed to determine the deposit's mineralization age and the source of its metallogenic materials and mineralization processes through investigations into its geological characteristics, Rb–Sr isotopes, and S–Pb isotopes. The orebodies of the Fang'an gold deposit in the Neoarchean Xigudui Formation primarily exhibit a vein-type structure. The ore-forming process can be divided into four stages: (i) the quartz stage (Py1); (ii) the quartz–pyrite stage (Py2); (iii) the polymetallic sulfide stage (Py3); and (iv) the carbonate stage. Of these, the main mineralization stage is also the main period in which gold mineralization occurs. In situ sulfur isotope results of pyrite (Py1 to Py3) in the first three mineralization stages, suggesting a contribution of sulfur from crust–mantle magmatic fluids. The δ34S values for Py2 (average 5.51‰) are higher than Py1 (average 4.45‰) and showed that the magmatic fluids mixed with meteoric waters. The δ34S values for Py3 (average 5.18‰) are lower than Py2 (average 5.51‰), revealing that it related fluid immiscibility. The lead isotopic compositions of sulfides within the ores possessed 206Pb/204Pb ratios ranging from 16.759 to 16.93, 207Pb/204Pb ratios ranging from 15.311 to 15.402, and 208Pb/204Pb ratios ranging from 37.158 to 37.548. These lead data were plotted close to the Xigudui Formation, relatively distant from the Mesozoic granites, indicating that the Xigudui Formation was the source of lead for the Late Mesozoic ores of the deposit. Taken together, due to the degassing of mantle-derived magma in the shallow parts of the crust, it can be determined that the sources of ore-forming sulfur and lead were crust–mantle magmatic activities in the Wuhe area. Rb–Sr dating of pyrite from Fang'an gold deposit reveals that the mineralization occurred at 126.89 ± 0.58 Ma. Considering the previous research into the dating of magmatic rocks in the Wuhe area, we propose that the genesis of the Fang'an gold deposit is closely associated with magmatic activities in the area at around 130 Ma. [ABSTRACT FROM AUTHOR]

In recent years, deep-learning-based WiFi fingerprinting has been intensively studied as a promising technology for providing accurate indoor location services. However, it still demands a time-consuming and labor-intensive site survey and suffers from the fluctuation of wireless signals. To address these issues, we propose a prototypical network-based positioning system, which explores the power of few-shot learning to establish a robust RSSI-position matching model with limited labels. Our system uses a temporal convolutional network as the encoder to learn an embedding of the individual sample, as well as its quality. Each prototype is a weighted combination of the embedded support samples belonging to its position. Online positioning is performed for an embedded query sample by simply finding the nearest position prototype. To mitigate the space ambiguity caused by signal fluctuation, the Kalman Filter estimates the most likely current RSSI based on the historical measurements and current measurement in the online stage. The extensive experiments demonstrate that the proposed system performs better than the existing deep-learning-based models with fewer labeled samples. [ABSTRACT FROM AUTHOR]

With the rapid development of nanotechnology, nanomaterials have been widely utilized in many industries and daily life applications due to their unique properties. However, their potential release and the human health/environmental consequences have raised public concern greatly. In this study, we compared the toxic effects of AgNPs and AgNO3 on Skeletonema costatum in 10, 100, and 500 μg·L−1 Ag treatments. In all the AgNP exposure experiments, cell membrane damage and growth inhibition occurred. However, the cellular damage only obviously appears on exposure to a high concentration of AgNO3. The antioxidant enzyme (SOD and CAT) activities and lipid peroxidation in Skeletonema costatum were also induced significantly in the AgNP treatments. In addition, the percentage of Ag release in seawater increased with the increase in AgNP concentrations (13%, 32% for 100 and 500 μg·L−1 AgNPs). Thus, the biotoxic effects of AgNPs were found to be due to a combination of the solubilization of particles into toxic metal ions and the nature of the nanoparticles. It was worth noting that the induction of oxidative stress and damage to the cell membrane comprised the dominant mechanism of toxicity for AgNPs. Therefore, the behavior of nanometals in seawater affects the biotoxic effect on the phytoplankton. These results shed light on the biological toxicity of nanometals and their possible toxicity mechanism. [ABSTRACT FROM AUTHOR]

In China, as statutory non-cultural relic buildings, the conservation and reuse of historic buildings have received increasing attention in recent years. Among them, the investigation and value evaluation of historic buildings are the basis and core of the conservation work, and many cities have explored related technologies and methods according to local conditions. This paper takes the historic building resources in Xi'an as the research object, with the core of historic building registration and the principles of scientificity and operability. It proposes the methods and basic processes for investigating historic building resources and constructs a step-by-step evaluation system for the historic buildings in Xi'an. This research first formulates a registration standard for the identification and evaluation of historic buildings, then applies the analytic hierarchy process, Delphi method, and fuzzy comprehensive evaluation method to assess the comprehensive value of historic buildings. Finally, it was recognized that the historic building resources are primarily modern and contemporary buildings, playing a significant role in the cultural continuity of the ancient capital, Xi'an. In its value evaluation, emphasis should be placed on the environmental landscape value and socio-cultural value. At the same time, it is necessary to consider the comprehensive value and sub-indicators of historic buildings so that they can guide conservation and adaptation practices in a targeted manner. [ABSTRACT FROM AUTHOR]

In this paper, a new modified social force model is proposed to simulate the single-file pedestrian flow at high densities. Since the pedestrians could only follow the preceding person in the single-file flow, the way in which the pedestrian chooses their destination is changed. It is set as the current position of the preceding pedestrian, rather than as one fixed location. In order to simulate the possible movement at high densities, the distance for calculating forces between pedestrians was reset, and the obstacles were divided into many particles. Next, the values of many model parameters were reset, and the ranges of possible parameters were discussed. Furthermore, the data from one large-scale single-file experiment were used for model validations. The simulation results of the fundamental diagrams, spatiotemporal diagrams and the time–headway distributions show that the new model can simulate the single-file movement well. The angular trajectories can help in understanding more about the simulation results. The comparisons between the statistical results of local flow rates and local densities show that, in most cases, the simulated and experimental results are quantitatively similar. This model could be a good choice for the high-density simulations of single-file pedestrian flow. [ABSTRACT FROM AUTHOR]

Purpose: The aim of our study was to investigate a comprehensive profile of streptozotocin (STZ)-induced early diabetic retinopathy (DR) mice to identify a risk scoring signature based on micorRNAs (miRNAs) for early DR diagnosis. Methods: RNA sequencing was performed to obtain the gene expression profile of retinal pigment epithelium (RPE) in early STZ-induced mice. Differentially expressed genes (DEGs) were determined with log2|fold change (FC)| > 1 and p value < 0.05. Functional analysis was carried out based on gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis and the protein–protein interaction (PPI) network. We predicted the potential miRNAs via online tools and ROC curves were then conducted. Three potential miRNAs with AUC > 0.7 were explored via public datasets and a formula was further established to evaluate DR severity. Results: In total, 298 DEGs (200 up-regulating and 98 down-regulating) were obtained through RNA sequencing. Hsa-miR-26a-5p, hsa-miR-129-2-3p and hsa-miR-217 were three predicted miRNAs with AUC > 0.7, suggesting their potential to distinguish healthy controls from early DR. The formula of DR severity score = 19.257 − 0.004 × hsa-miR-217 + 5.09 × 10−5 × hsa-miR-26a-5p − 0.003 × hsa-miR-129-2-3p was established based on regression analysis. Conclusions: In the present study, we investigated the candidate genes and molecular mechanisms based on RPE sequencing in early DR mice models. Hsa-miR-26a-5p, hsa-miR-129-2-3p and hsa-miR-217 could work as biomarkers for early DR diagnosis and DR severity prediction, which was beneficial for DR early intervention and treatment. [ABSTRACT FROM AUTHOR]

Excessive intake of high-caffeine tea will induce health-related risk. Therefore, breeding and cultivating tea cultivars with less caffeine is a feasible way to control daily caffeine intake. Cocoa tea (Camellia ptilophylla Chang) is a wild tea plant which grows leaves with little or no caffeine. However, the vegetative propagation of cocoa tea plants is difficult due to challenges with rooting. Whether natural seeds collected from wild cocoa tea plants can be used to produce less-caffeinated tea remains unknown, because research on the separation of traits among the seed progeny population is lacking. The present study was set to investigate the variation of caffeine and other chemical compositions in seed-propagated plant individuals using colorimetric and HPLC methods. It shows that there were great differences in chemical composition among the seed-propagated population of wild cocoa tea plants, among which some individuals possessed caffeine contents as high as those of normal cultivated tea cultivars (C. sinensis), suggesting that the naturally seed-propagated cocoa tea seedlings are not suitable for directly cultivating leaf materials to produce low-caffeine tea. Therefore, the cocoa tea plants used for harvesting seeds for growing low-caffeine tea plants should be isolated in order to prevent their hybridization with normal cultivated C. sinensis plants. Interestingly, the leaves of cocoa tea seedlings contained high levels of gallocatechin gallate (GCG) and would be a good source of leaf materials for extracting more stable antioxidant, because GCG is a more stable antioxidant than epigallocatechin gallate (EGCG), the dominant component of catechins in normal cultivated tea cultivars. Some plant individuals which contained low levels of caffeine along with high levels of amino acids and medium levels of catechins, are considered to be promising for further screening of less-caffeinated green tea cultivars. [ABSTRACT FROM AUTHOR]

Kunming city is located in the middle of Yunnan Province. Due to large-scale groundwater exploitation and urban development in recent years, this area has been affected by surface subsidence. In this paper, Interferometric Synthetic Aperture Radar (InSAR) and Global Navigation Satellite System (GNSS) data are used to monitor the surface subsidence in Kunming city area for better analysis and understanding. The study used data of Sentinel-1A from 2018 to 2020 with atmospheric correction based on GACOS to calculate the average annual subsidence rate in Kunming city area, and the results show that the maximum subsidence rate is 48 mm/year. The subsidence obtained by InSAR is compared with the vertical deformation information obtained by eight GNSS stations in continuous operation in the study area. The subsidence rate trend show by the two methods is consistent, which further verifies the validity of InSAR data to reflect the local deformation. Experimental results shown that the eastern and northeastern Dianchi lake areas were affected by underground resources mining, and the induced surface subsidence characteristics were obvious, with the surface subsidence rate reachde 48 mm/year and 37 mm/year respectively. The Kunyang Phosphate Mine also had different degrees of mining subsidence disaster, with the maximum subsidence rate reached 36 mm/year. The subsidence rate of InSAR and GNSS has the same trend on the whole. However, GNSS sites are generally located in stable areas, the settlement amount obtained in the same time period is somewhat different from that of InSAR. [ABSTRACT FROM AUTHOR]

This paper reports on the flexural behavior of nine steel fiber reinforced-recycled aggregate concrete (SFRAC) beams through combined experimental and finite element analysis. The test parameters in this study include the steel fiber volume fraction, recycled aggregate replacement ratio, and concrete strength. The failure modes, crack development, load-deflection curves, and flexural bearing capacity of SFRAC beams are investigated in detail. The test results indicated that cracks and concrete crushing are formed in the compression zone of all specimens. The flexural bearing capacity of SFRAC beams increases with the increase of steel fiber volume fraction and concrete strength and the decrease of recycled aggregate replacement ratio. In addition, the results are compared with those of the finite element analysis. Based on the uniaxial compressive constitutive model of SFRAC, a new model for calculating the flexural bearing capacity of SFRAC beams is proposed. The prediction and test results are compared to evaluate the accuracy of the developed formula. The studies may provide a considerable reference for designing this type of structure in engineering practice. [ABSTRACT FROM AUTHOR]

As an important part of the northern Huaiyang tectonic belt, the Mesozoic Xiaotian basin hosts a series of gold and alunite deposits. However, the ages of these deposits remain unclear, constraining the further understanding of the genesis of these deposits. In this work, zircon LA–ICP-MS and alunite 39Ar/40Ar isotopic dating studies were carried out on the andesitic porphyrite and alunite of the Saozhouhe alunite deposit, respectively. LA–ICP-MS zircon U–Pb dating for the Saozhouhe andesitic porphyrite yields a weighted average age of 122.8 ± 0.9 Ma (MSWD = 1.8), indicating that these volcanic rocks were formed in the Early Cretaceous period. The alunite 39Ar/40Ar dating yields a plateau age of 121.0 ± 1.1 Ma (MSWD = 4.4) and an isochron age of 121.2 ±1.9 Ma (MSWD = 8.5), indicating that the alunite was also formed in the Early Cretaceous period. Our finding confirms that the formation of the Saozhouhe alunite deposit is genetically related to the Cretaceous volcanic magmatism, which has great significance in the metallogenetic regularity of and further ore prospecting in the Xiaotian basin. [ABSTRACT FROM AUTHOR]

The redistribution of surface mass (e.g., atmosphere, soil water, oceans, and groundwater) can cause load responses, resulting in vertical deformations of the crust. Indeed, the global navigation satellite system (GNSS)-based continuously operating reference stations (CORS) are able to accurately measure the vertical deformation caused by surface mass loads. In this study, the CORS was used to invert groundwater storage anomalies (GWSA), represented by the equivalent water height (EWH), after removing the effect of the non-groundwater surface mass load (atmospheric, groundwater, and non-tidal oceanic loads) from the vertical deformation monitored by CORS. In addition, the global and regional high-resolution surface mass models were combined to calculate the high-precision load deformation field in in western Yunnan using the remove–restore method, thereby obtaining more accurate surface mass load data and improving the accuracy of the inverted GWSA results. In order to assess the feasibility of the CORS inversion for the GWSA used, 66 CORS stations in western Yunnan Province were considered, presenting weekly GWSA data from 10 January 2018 to 31 December 2020. The results revealed significant seasonal variation in GWSA in the study area, showing an amplitude range of −200–200 mm. This approach is based on the already-established CORS network without requiring additional set-up costs. In addition, the reliability of CORS inverse results was assessed using Gravity Recovery and Climate Experiment (GRACE) inverse results and actual groundwater monitoring data. According to the obtained results, GWSA can be monitored by both CORS and GRACE data; however, CORS provided a more effective spatiotemporal resolution of GWSA. Therefore, the CORS network combined with surface mass load data is able to effectively monitor the spatiotemporal dynamics of GWSA in small-scale areas and provides important references for the study of hydrology. [ABSTRACT FROM AUTHOR]

The Chang'e-4 (CE-4) lunar probe, the first soft landing spacecraft on the far side of the Moon, successfully landed in the Von Kármán crater on 3 January 2019. Geological studies of the landing area have been conducted and more intensive studies will be carried out with the in situ measured data. The chronological study of the maria basalt surrounding the CE-4 landing area is significant to the related studies. Currently, the crater size-frequency distribution (CSFD) technique is the most popular method to derive absolute model ages (AMAs) of geological units where no returned sample is available, and it has been widely used in dating maria basalt on the lunar surface. In this research, we first make a mosaic with multi-orbital Chang'e-2 (CE-2) images as a base map. Coupled with the elevation data and FeO content, nine representative areas of basalt units surrounding the CE-4 landing area are outlined and their AMAs are derived. The dating results of the nine basalt units indicate that the basalts erupted from 3.42 to 2.28 Ga ago in this area, a period much longer than derived by previous studies. The derived chronology of the above basalt units establishes a foundation for geological analysis of the returned CE-4 data. [ABSTRACT FROM AUTHOR]

As a result of the development of wireless indoor positioning techniques such as WiFi, Bluetooth, and Ultra-wideband (UWB), the positioning traces of moving people or objects in indoor environments can be tracked and recorded, and the distances moved can be estimated from these data traces. These estimates are very useful in many applications such as workload statistics and optimized job allocation in the field of logistics. However, due to the uncertainties of the wireless signal and corresponding positioning errors, accurately estimating movement distance still faces challenges. To address this issue, this paper proposes a movement status recognition-based distance estimating method to improve the accuracy. We divide the positioning traces into segments and use an encoder–decoder deep learning-based model to determine the motion status of each segment. Then, the distances of these segments are calculated by different distance estimating methods based on their movement statuses. The experiments on the real positioning traces demonstrate the proposed method can precisely identify the movement status and significantly improve the distance estimating accuracy. [ABSTRACT FROM AUTHOR]

To improve the seismic behavior of shear walls, a new composite shear wall composed of a steel-fiber-reinforced high-strength concrete (SFRHC) web and two square concrete-filled steel tube (CFST) columns, namely a steel-fiber-reinforced concrete shear wall with CFST columns, is proposed in this paper. Therefore, the main purpose of this paper is to present an experimental investigation of the seismic behavior of the SFRHC shear wall with CFST columns. Pseudo-static tests were carried out on seven composite shear walls, and the seismic performance of the shear walls was studied and quantified in terms of the aspects of energy consumption, ductility and stiffness degradation. Furthermore, the experimental results indicated that adding steel fiber can effectively restrain the crack propagation of composite shear walls and further help to improve the ductility and energy dissipation capacity of composite shear walls and delay the degradation of their lateral stiffness and force. Moreover, the seismic behavior of the SFRHC shear wall with CFST columns was obviously superior to that of the conventionally reinforced shear wall, in terms of load-bearing capacity, ductility, stiffness and energy dissipation capacity, because of the confinement effect of the CFST columns on the web. Finally, the preliminary study demonstrated that the composite shear wall has good potential to be used in regions with high seismic risk. [ABSTRACT FROM AUTHOR]

An undetermined saprobic fungal taxon from Yunnan (China) is revealed as a new genus in Scortechiniaceae (Coronophorales). The novel taxon, Yuxiensis, is characterized by immersed to erumpent, semi-globose ascomata, which are not surrounded by any tomentum or conspicuous subiculum, a subcylindrical quellkörper in the centrum, clavate asci with long pedicels and allantoid hyaline ascospores with granular contents. Maximum likelihood and Bayesian posterior probability analyses based on LSU, ITS, tef1 and rpb2 sequence data depict a close phylogenetic relationship of the new genus to Pseudocatenomycopsis, hence, confirming its placement in Scortechiniaceae. Parasympodiellaceae, thus far belonging to Parasympodiellales, is transferred to Coronophorales based on multi-gene phylogenetic evidence. Additionally, the incertae sedis monotypic genus Arthrocristula is treated as a synonym of Parasympodiella, with Arthrocristula hyphenata recombined as Parasympodiella hyphenata comb. nov., as the type strain of Arthrocristula hyphenata clusters inside the Parasympodiellaceae clade along with other Parasympodiella taxa. [ABSTRACT FROM AUTHOR]

Steel fiber reinforced concrete (SFRC) is a novel material of concrete, which has a great potential to be used in practical engineering. Based on the finite element software Opensees, the main objective of this paper presented a numerical simulation method on investigating the seismic behavior of SFRC–beam-column joints (BCJs) through modifying the calculation method of joint shear and longitudinal reinforcement slip deformations. The feasibility and accuracy of the numerical modeling method were verified by comparing the computed results with experimental data in terms of the hysteresis curves, skeleton curves, feature points, energy dissipation, and stiffness degradation. And then, the influences of some key parameters on the seismic behavior of BCJs were investigated and discussed in detail. The parametric studies clearly illustrated that both adding the steel fiber and increasing the stirrup amount of joint core area could significantly improve the seismic behavior of BCJs. The axial compression ratio had limited influence on the seismic behavior of BCJs. Finally, based on the main factors (steel fiber volume ratio, stirrup amount, and axial compression ratio), a formula for predicting ultimate shear capacity is derived. [ABSTRACT FROM AUTHOR]

Tianwen-1, China's first Mars exploration mission, was successfully landed in the southern part of Utopia Planitia on 15 May 2021 (UTC+8). Timely and accurately determining the landing location is critical for the subsequent mission operations. For timely localization, the remote landmarks, selected from the panorama generated by the earliest received Navigation and Terrain Cameras (NaTeCam) images, were matched with the Digital Orthophoto Map (DOM) generated by high resolution imaging camera (HiRIC) images to obtain the initial result based on the triangulation method. Then, the initial localization result was refined by the descent images received later and the NaTeCam DOM. Finally, the lander location was determined to be (25.066°N, 109.925°E). Verified by the new orbital image with the lander and Zhurong rover visible, the localization accuracy was within a pixel of the HiRIC DOM. [ABSTRACT FROM AUTHOR]

Steel fiber and Nano–SiO2 reinforced concrete is a novel material of concrete which has great potential to be used in practical engineering. However, there is relatively little literature available on the flexural behavior of steel fiber and Nano–SiO2 materials reinforced concrete (SFNMRC) beams. Hence, the main objective of this paper is to investigate the flexural performance of SFNMRC beams through combined experimental and theoretical studies. A total of 10 specimens were tested to investigate the flexural behavior and the effect of some key parameters, including concrete strength, the volume fraction of steel fiber, and the amount of Nano–SiO2. The load vs. deflection curves of SFNMRC beams during the whole loading process were analyzed in detail. The failure mode was discussed in detail, and the specimens all behaved in a very ductile manner. Furthermore, the test results indicated that bending cracks and concrete crushing were formed in the compression zone of all specimens. With the increase in concrete strength and the volume fraction of steel fiber, both the cracking load and ultimate load of beams increased. The amount of Nano–SiO2 had a limited effect on the flexure performance. Finally, the calculation formula for predicting the flexural bearing capacity of SFNMRC beams was derived with consideration of the effect of steel fiber on the cracked sections after beam cracking. The predicted results show satisfactory agreement with both experimental results. The studies may provide a considerable reference for designing this type of structure in engineering practice. [ABSTRACT FROM AUTHOR]

The present research study aims to investigate numerically the behavior of steel fiber-reinforced high-strength concrete (SFRHC) beam–column joints (BCJs) under seismic action. Based on the plastic damage constitutive model of concrete and elastic–plastic mixed-strengthen constitutive model of steel material, the finite element software ABAQUS was utilized to establish the 3D finite element (FE) model of BCJs. Additionally, the feasibility and accuracy of the numerical simulation were verified by comparing the computed results and experimental observations in terms of the hysteresis curves, skeleton curves, and failure mode. Furthermore, based on the validated FE modeling approach, load vs. displacement hysteresis curves of SFRHC–BCJs during the loading process were analyzed in detail; the failure process was also investigated. Furthermore, the effect of various parameters on the seismic behavior of BCJs was analyzed comprehensively, including the concrete strength, the volume ratio of steel fiber, and the stirrup ratio in the core area. Finally, parametric studies illustrated that increasing the concrete strength helps in enhancing the ultimate load, while the ductility decreased noticeably. Both adding the steel fiber and increasing the stirrup ratio can significantly improve the seismic performance of BCJs. [ABSTRACT FROM AUTHOR]