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A utility tunnel is an infrastructure that consolidates multiple municipal pipeline systems into a shared underground passage. As long linear structures inevitably cross different soils, this paper aims to accurately assess the seismic damage to a shallow-buried utility tunnel in a non-homogeneous zone by employing a viscous-spring artificial boundary and deriving the corresponding nodal force equations. The three-dimensional model of the utility tunnel-soil system is established using finite element software, and a plug-in is developed to simulate the three-dimensional oblique incidence of SV waves with a horizontal non-homogeneous field. In this study, the maximum interstory displacement angle of the utility tunnel is used as the damage indicator. Analysis of structural vulnerability based on IDA method using PGA as an indicator of seismic wave intensity, which considers the angle of oblique incidence of SV waves, the type of seismic waves, and the influence of the nonhomogeneous field on the seismic performance of the utility tunnel. The results indicate that the failure probability of the utility tunnel in different soil types increases with the incident angle and PGA. Additionally, the failure probability under the pulse wave is higher than that under the non-pulse wave; Particular attention is given to the states of severe damage (LS) and collapse (CP), particularly when the angle of incidence is 30 degrees and the PGA exceeds 0.6g, conditions under which the probability of failure is higher. Additionally, the failure probability of the non-homogeneous zone is greater than that of sand and clay; the maximum interlayer displacement angle increases with the incident angle, accompanied by greater PGA dispersion, indicating the seismic wave intensity. The maximum inter-layer displacement angle increases with the incident angle, and the dispersion of the seismic wave intensity indicator (PGA) becomes greater. This paper proposes vulnerability curves for different working conditions, which can serve as a reference for the seismic design of underground structures.

期刊论文 2025-10-01 DOI: 10.1016/j.soildyn.2025.109537 ISSN: 0267-7261

Increasing numbers of complex structures are being constructed with the acceleration of urbanization. The complex dynamic characteristics pose challenges to the seismic design of large chassis. This paper investigates the seismic response and damage evolution of complex structures using linear and nonlinear dynamic explicit analysis under obliquely incident SV waves. A twodimensional finite element model considering soil-structure interaction (SSI) is developed using fiber beam elements. Elastic and elastoplastic damage constitutive models are employed. A comprehensive numerical analysis is conducted to investigate the influence of key parameters, including incidence angles, ground motion characteristics, and site types, on the seismic response and damage evolution of complex structures. The results of this study indicate that, in the elastic stage, the seismic response of the frame-shear wall structure is reduced in the case of oblique incidence compared to vertical incidence. Specifically, the inter-story drift ratio is reduced by 60% at an incidence angle of 30 degrees. In comparison to vertical incidence, the inter-story drift ratio and horizontal acceleration of the underground structure are reduced under oblique incidence. Conversely, in the elastic stage, the beam-end vertical displacement ratio and vertical acceleration exhibit increases of 57% and 36%, respectively. In the elastoplastic stage, as the incidence angle increases, the damage to the beams of the underground structure becomes more significant, while the damage to the frame-shear wall structure relatively decreases. Low-frequency ground motion and soft soil amplify the structural response compared to high-frequency and hard soil.

期刊论文 2025-06-01 DOI: 10.1016/j.engfailanal.2025.109500 ISSN: 1350-6307

With the rapid development of infrastructure in western China, numerous arch bridges have been constructed as vital transportation hubs spanning river canyons. Understanding the impact of canyon topography on the seismic response of long-span half-through arch bridges crossing canyons is essential. This study first establishes a seismic input method for oblique P-wave and SV-wave incidence, based on the viscous-spring artificial boundary theory, which transforms ground motions into equivalent nodal loads on artificial boundaries. The feasibility of this proposed method is systematically validated. Subsequently, parametric investigations are carried out to explore the effects of seismic wave incidence angle, canyon depth-to-breadth ratio and soil elastic modulus on the ground motion amplification characteristics in V-shaped canyons under oblique P-wave and SV-wave excitations. Finally, dynamic response patterns of the arch ribs and the stress-strain relationships at critical structural components are thoroughly analyzed. Key findings reveal that SV-waves induce significantly different ground motion amplification effects compared to P-waves, with the wave incidence angle and canyon width-to-depth ratio being crucial influencing factors. The connection between the arch footings and the concrete cross braces constitutes the most vulnerable region, frequently exhibiting maximum stresses that exceed the yield strength of C40 concrete under multiple scenarios. Notably, when the depth-to-breadth ratio (D/B) is 0.75, the peak stress at the arch footings reaches 5.18 x 10(7)kPa, surpassing the yield stress threshold of C40 concrete. These findings highlight the need for special seismic fortification measures at these critical connections during bridge design. This research offers valuable insights into the seismic design of long-span arch bridges in complex topographic conditions.

期刊论文 2025-05-29 DOI: 10.1142/S0219455426502962 ISSN: 0219-4554

Cyst nematodes are among the major plant-parasitic nematodes worldwide, and they cause significant damage to Brassicaceae crops, including Kimchi-cabbage, in Korea. To survey the incidence of cyst nematodes in Kimchi-cabbage fields, 469 soil samples were collected from the main producing areas between 2018 and 2021. Only cyst nematodes belonging to the genus Heterodera were investigated, and the overall nematode incidence was found to be 40%. Regionally, the highest incidence was observed in Taebaek, reaching 89%, with mean densities of cysts and eggs per 500 cm3 of soil recorded at 522 and 49,734, respectively. Based on Bayesian analysis of the mitochondrial DNA cytochrome c oxidase subunit I gene sequence, the cyst nematodes were identified as four species: clover cyst nematode (Heterodera schachtii, 4%), and white soybean cyst nematode (H. sojae, HSo, 2%). Mixed infestations were found in some fields, with HT + HG (4%) and HG + HSo (1%). These results indicate that HT is the dominant species in the main Kimchi-cabbage producing areas in Korea. In conclusion, implementing effective HT management strategies is critical to minimize economic losses in Kimchi-cabbage production in Korea.

期刊论文 2025-04-01 DOI: 10.5423/PPJ.OA.11.2024.0179 ISSN: 1598-2254

A horizontal non-homogeneous field adversely affects the seismic resistance of both the utility tunnel and its internal pipes, with seismic waves obliquely incident on the underground structure causing more significant damages. To address these issues, this study, based on a viscous-spring artificial boundary, derives and validates the equivalent junction force formula for the horizontal non- homogeneous field. It then establishes a three-dimensional finite element model of the utility tunnel, pipes, and surrounding soil to obtain the acceleration and strain responses of the utility tunnel and its internal pipes under seismic loading. Finally, it investigates the impact of different incidence angles of shear waves (SV waves) on the response of the utility tunnel and its internal pipes. It was found that as the PGA increases from 0.1 to 0.4 g, both peak acceleration and strain of the utility tunnel and its internal pipes increase. The peak acceleration of the utility tunnel and pipes initially decreases and then increases with the angle of incidence, while the strain increases with the angle of incidence, reaching its peak value when the angle of incidence is 30 degrees. The acceleration and strain responses of the utility tunnel and pipe are higher in sand than in clay, with the peak acceleration strongly correlating with the angle of incidence of ground shaking. The findings of this study provide valuable insights into the seismic design of horizontal non-homogeneous field utility tunnel systems.

期刊论文 2025-01-01 DOI: 10.3934/geosci.2025004 ISSN: 2471-2132

Liquid storage tanks are often arranged in rows with small spacing in practical applications, which may cause mutual influence under earthquake action and even aggravate the seismic damage of liquid storage tanks. Adding the vibration barrier (ViBa) into the foundation between the adjacent liquid storage tanks forms a new type of seismic control method. Considering important factors such as liquid-solid-soil coupling, liquid sloshing behavior, and structure-soil-structure interaction (SSSI), a refined 3D numerical calculation model of the adjacent liquid storage tanks with three ViBas is established by ADINA. The influence of seismic wave incidence angle on the seismic responses of the liquid storage tanks and the control effect of ViBa are studied, and the parameter influence analysis is carried out. The results show that the ViBa significantly control the seismic responses and liquid sloshing wave height of the adjacent liquid storage tanks, and the damping ratio of the liquid sloshing wave height is between 30% and 40%. When the seismic incidence angle is between 30(degrees) and 60(degrees), the dynamic responses of the liquid storage tank is larger. With the increase of the seismic incidence angle, the control effect of the ViBa on the effective stress, hoop stress, axial compressive stress, and liquid pressure first increases and then decreases. When the liquid storage tank is close to full state, the control effect is most significant at an incidence angle of 60(degrees), and the control effect of the ViBa on the liquid storage tank with medium height-diameter ratio is the best.

期刊论文 2024-11-30 DOI: 10.1142/S0219455424502547 ISSN: 0219-4554

. The berry borer is the most damaging insect pest of coffee worldwide, affecting both yield and quality. Due to its economic importance, the borer has been the subject of considerably research around the world, both to determine its biology, as well as to develop economically and environmentally viable control technologies. Much of the work has focused on biological control with parasitoids and entomopathogens. The objective of this study was to isolate, identify and evaluate strains of Beauveria bassiana native to the coffee growing areas of Nayarit against the coffee berry borer under field conditions. The strains were obtained from soil and coffee fruit samples from 15 coffee orchards and were evaluated in an organic coffee production orchard. In general, the strains of B. bassiana showed good performance against the coffee berry borer with effectiveness higher than 76%. In the region of study, if control measures are not applied, the percentages of infestation could reach up to 56%. Regional B. bassiana strains are considered an option for biological control of the coffee berry borer.

期刊论文 2024-09-01 DOI: 10.19136/era.a11n3.4148 ISSN: 2007-901X

This study established a numerical model for soil-structure interaction (SSI) to examine the effects of the spatial incidence angle of SV waves and soil nonlinearity, utilizing viscoelastic artificial boundaries (VAB) and equivalent nodal force (ENF) method. Both the foundation's and superstructure's torsion and rocking responses were then analyzed. The findings indicate that subjected to spatially oblique incident SV waves, the rectangular foundation primarily has the rocking response while the torsional response is negligible. Furthermore, the maximum torsional and rocking angles about the x-axis at each frame floor are significantly enlarged by comparison with the perpendicular incident case. Moreover, the soil nonlinearity could increase the foundation's rocking angle and enlarge the maximum torsion and rocking responses of the structure's floors. Consequently, structural seismic damage assessment requires considering both the soil nonlinearity and incident seismic wave angles.

期刊论文 2024-09-01 DOI: 10.1016/j.soildyn.2024.108868 ISSN: 0267-7261

Multi-span reinforced concrete (RC) curved box-girder bridges are commonly designed to facilitate traffic flow at highway interchanges. The Aksemsettin Viaduct (henceforth, A Viaduct for brevity) in Istanbul, Turkey, is an eleven-span interchange bridge with a total length of 596.8 m. Located in a high seismicity zone, the A Viaduct is designed with a curved deck, multiple bearings that have different isolation mechanisms at different bents and directions, ten rectangular columns with unequal heights, and a mix of pile foundations and spread footings. The significant length of the viaduct crossed by eleven spans also makes it susceptible to varying ground motion excitations at different foundations. To evaluate the effects of the degree of modeling detail and analysis complexity on the estimated seismic performance, the present study conducts a comprehensive fragility assessment of the specimen viaduct under various ground motion excitation schemes. First, a three-dimensional finite element model is developed with detailed simulations for the deck, columns, bearings, foundations, and abutment components. To enable different ground motion excitations at each foundation, 57 sets of spatially varying ground motions are simulated by considering the realistic surface topography and soil stratigraphy at the bridge site. Cyclic pushover analyses are performed along multiple loading directions to develop the directiondependent capacity limit state models for hollow rectangular columns. Subsequently, a demand-capacity ratio method is utilized to develop reliable fragility models for bridge columns. Component- and system-level fragilities of the A Viaduct are then assessed under uniform versus multi-support excitations, vertical motions, and ground motions with varying incidence angles. To further capture the seismic damage discrepancies of the same components at different locations, seismic repair cost ratios of the A Viaduct are assessed when subjected to uniform and multi-support excitations. This study highlights the significance of considering multi-support excitations to achieve more realistic seismic fragility and loss estimates for multi-span long curved highway bridges.

期刊论文 2024-05-01 DOI: 10.1016/j.soildyn.2024.108585 ISSN: 0267-7261

The literature presents the preserving effect of biological coatings developed from various microbial sources. However, the presented work exhibits its uniqueness in the utilization of halophilic exopolysaccharides as food coating material. Moreover, such extremophilic exopolysaccharides are more stable and economical production is possible. Consequently, the aim of the presented research was to develop a coating material from marine exopolysaccharide (EPS). The significant EPS producers having antagonistic attributes against selected phytopathogens were screened from different marine water and soil samples. TSIS01 isolate revealed the maximum antagonism well and EPS production was selected further and characterized as Bacillus tequilensis MS01 by 16S rRNA analysis. EPS production was optimized and deproteinized EPS was assessed for biophysical properties. High performance thin layer chromatography (HPTLC) analysis revealed that EPS was a heteropolymer of glucose, galactose, mannose, and glucuronic acid. Fourier transform infrared spectroscopy, X-ray diffraction, and UV-visible spectra validated the presence of determined sugars. It showed high stability at a wide range of temperatures, pH and incubation time, approximate to 1.63 x 10(6) Da molecular weight, intermediate solubility index (48.2 +/- 3.12%), low water holding capacity (12.4 +/- 1.93%), and pseudoplastic rheologic shear-thinning comparable to xanthan gum. It revealed antimicrobial potential against human pathogens and antioxidants as well as anti-inflammatory potential. The biocontrol assay of EPS against phytopathogens revealed the highest activity against Alternaria solani. The EPS-coated and control tomato fruits were treated with A. solani suspension to check the % disease incidence, which revealed a significant (p < 0.001) decline compared to uncoated controls. Moreover, it revealed shelf-life prolonging action on tomatoes comparable to xanthan gum and higher than chitosan. Consequently, the presented marine EPS was elucidated as a potent coating material to mitigate post-harvest losses.

期刊论文 2024-02-01 DOI: 10.3390/molecules29030695
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