Search Results (181)

Concrete is a fundamental material in structural engineering, widely used in critical infrastructure such as bridges, nuclear power plants, and dams. These structures may be subjected to extreme dynamic loads resulting from natural disasters, industrial accidents, or missile impacts. Therefore, a comprehensive understanding of concrete behavior under high strain rates is essential for safe and resilient design. Experimental investigations, particularly spalling tests, have highlighted the strain-rate sensitivity of concrete in dynamic tensile loading conditions. This study presents a macroscopic 3D discrete element model specifically developed to simulate the dynamic response of concrete subjected to extreme loading. Unlike conventional continuum-based models, the proposed discrete element framework is particularly suited to capturing damage and fracture mechanisms in cohesive materials. A key innovation lies in incorporating a physically grounded strain-rate dependency directly into the local cohesive laws that govern inter-element interactions. The originality of this work is further underlined by the validation of the discrete element model under dynamic tensile loading through the simulation of spalling tests on normalstrength concrete at strain rates representative of severe impact scenarios (30–115 s⁻¹). After calibrating the model under quasi-static loading, the simulations accurately reproduce key experimental outcomes, including rear-face velocity profiles and failure characteristics. Combined with prior validations under high confining pressure, this study reinforces the capability of the discrete element method for modeling concrete subjected to extreme dynamic loading, offering a robust tool for predictive structural assessment and design. Full article

Collar monopile foundation is a new type of offshore wind power foundation. This paper explores the horizontal bearing performance of collar monopile foundation in saturated cohesive soil through a combination of physical experiments and numerical simulations. After analyzing the deformation characteristics of the pile–soil system under horizontal load through static load tests, horizontal cyclic loading tests were conducted at different cycles to study the cumulative deformation law of the collar monopile. Based on a stiffness degradation model for soft clay, a USDFLD subroutine was developed in Fortran and embedded in ABAQUS. Coupled with the Mohr–Coulomb criterion, it was used to simulate the deformation behavior of the collar monopile under horizontal cyclic loading. The numerical model employed the same geometric dimensions and boundary conditions as the physical test, and the simulated cumulative pile–head displacement under 4000 load cycles showed good agreement with the experimental results, thereby verifying the rationality and reliability of the proposed simulation method. Through numerical simulation, the distribution characteristics of bending moment and the shear force of collar monopile foundation were studied, and the influence of pile shaft and collar on the horizontal bearing capacity of collar monopile foundation at different loading stages was analyzed. The results show that as the horizontal load increases, cracks gradually appear at the bottom of the collar and in the surrounding soil. The soil disturbance caused by the sliding and rotation of the collar will gradually increase, leading to plastic failure of the surrounding soil and reducing the bearing capacity. The excess pore water pressure in shallow soil increases rapidly in the early cycle and then gradually decreases with the formation of drainage channels. Deep soil may experience negative pore pressure, indicating the presence of a suction effect. This paper can provide theoretical support for the design optimization and performance evaluation of collar monopile foundations in offshore wind power engineering applications. Full article

Angola’s cultural mosaic and ethnolinguistic diversity reflect the multilocational traditional customs and power, which are key to the country’s social organisation. A Soba, a traditional leader whose status is recognised by the Angolan Constitution, exerts political influence, shapes the collective life, and helps to preserve cultural identity. Customary law, entrenched after independence, became central to the political and administrative restructuring of the country, which had an impact on decentralisation efforts and legal pluralism. This study analyses the traditional leadership of Sobas in Angola in the context of placemaking and territorial co-management. Backed by the theory of Afrocentricity, a multidisciplinary approach is adopted towards setting Africans as the subjects of their own history. It is based on a literature review and critical analysis of the interaction between administrative law and customary law, which imply a hybrid model for territorial governance. The results indicate that the influence of Sobas on decision-making directly affects the use of the territory and cultural development, highlighting the importance of institutionalising traditional power. This paper suggests that recognising and strengthening such hybrid models is key to promoting territorial cohesion and fostering community engagement, whilst integrating traditional practices can result in more inclusive and effective public policies. Full article

This study examines the critical role of institutional quality in driving corporate adaptation to climate change within the EU-27 member states from 2006 to 2023. It aims to investigate how governance factors—control of corruption, government effectiveness, rule of law, and regulatory quality—influence business strategies for environmental resilience and sustainability, focusing on environmental investments and industrial production. Employing fixed and random effects regression models on a balanced panel dataset, we analyze two dependent variables: environmental protection investment corporations (EPIC), measuring investments in pollution prevention and environmental degradation reduction, and industrial production (IP), reflecting output in mining, manufacturing, and utilities. A composite institutional quality index, derived through principal component analysis (PCA) from the four governance indicators, captures their collective impact, reducing multicollinearity and enhancing analytical robustness. Control variables, including final energy consumption, environmental tax revenues, expenditure on environmental protection, and a Paris Agreement dummy, are incorporated to test the institutional quality effect. Results demonstrate that higher institutional quality significantly enhances EPIC, particularly in countries with greater environmental tax revenues, indicating that robust governance and fiscal policies incentivize sustainable corporate investments. Conversely, the effect on IP is less consistent, with higher fossil energy consumption and lower environmental tax revenues driving production, suggesting a reliance on high-polluting industries. The Paris Agreement positively influences IP, reflecting stronger climate-focused industrial strategies post-2015. These findings underscore the pivotal interplay between institutional quality and environmental fiscal policies in fostering corporate adaptation to climate change. Over the long term, strong governance is essential for aligning business practices with sustainability goals, reducing environmental degradation, and mitigating climate risks across the EU. This study highlights the need for cohesive policies to support green investments and transition industries toward renewable energy sources, addressing disparities in environmental performance among EU member states. Full article

Wood, steel, and concrete constitute the three predominant structural materials employed in contemporary commercial and residential construction. In composite applications, bond interfaces between these materials represent critical structural junctures that frequently exhibit a reduced load-bearing capacity, rendering them susceptible to the initiation of cracks. To elucidate the fracture propagation mechanisms at composite material interfaces, this study implements the cohesive zone method (CZM) to numerically simulate interfacial cracking behavior in two material systems: glued laminated timber (GLT) and reinforced concrete (RC). The adopted CZM framework utilizes a progressive delamination approach through cohesive elements governed by a bilinear traction–separation constitutive law. This methodology enables the simulation of interfacial failure through three distinct fracture modes: mode I (pure normal separation), mode II (pure in-plane shear), and mixed-mode (mode m) failure. Numerical models were developed for GLT beams, RC beams, and RC slab structures to investigate the propagation of interfacial cracks under monotonic loading conditions. The simulation results demonstrate strong agreement with experimental cracking observations in GLT structures, validating the CZM’s efficacy in characterizing both mechanical behavior and crack displacement fields. The model successfully captures transverse tensile failure (mode I) parallel to wood grain, longitudinal shear failure (mode II), and mixed-mode failure (mode m) in GLT specimens. Subsequent application of the CZM to RC structural components revealed a comparable predictive accuracy in simulating the interfacial mechanical response and crack displacement patterns at concrete composite interfaces. These findings collectively substantiate the robustness of the proposed CZM framework in modeling complex fracture phenomena across diverse construction material systems. Full article

While digital religion and digital protest can ideally serve the common good, religious nationalist and fundamentalist movements have exploited these tools to disrupt the social fabric and create dangerous political outcomes. This paper examines how religious communicators within Tehreek-e-Labbaik Pakistan (TLP) and Alternative for Germany (AfD) perceive and enact their responsibility within digital spaces, leveraging the power of “networked communities” and the collective identity of the digital “crowd” to advance their agendas of religious fundamentalism and political conservatism. Bypassing traditional media, groups like the AfD and TLP exploit digital religion to build communities, spread propaganda that merges religion with national identity, frame political issues as religious mandates, and mobilize collective action. Campbell’s concept of the “networked community” demonstrates how digital technologies form decentralized, fluid, and global religious communities, distinct from traditional, geographically bound ones. Both the TLP and AfD have tapped into this new digital religious space, shaping and mobilizing political and religious identities across virtual borders. Gerbaudo’s idea of the “digital crowd” complements this by examining how collective action in the digital age reshapes mass mobilization, with social media transforming how political movements operate in the 21st century. Although the AfD’s platform is not overtly religious, the party strategically invokes ethno-Christian identity, framing opposition to Islam and Muslim immigration as a defense of German cultural and Christian values. Similarly, the TLP promotes religious nationalism by advocating for Pakistan’s Islamic identity against secularism and liberalism and calling for strict enforcement of blasphemy laws. Recognizing digital spaces as tools co-opted by religious nationalist movements, this paper explores how communicators in these movements understand their responsibility for the social and long term consequences of their messages. Using Luhmann’s systems theory—where communication is central to social systems—this paper analyzes how the TLP and AfD leverage individuals’ need for purpose and belonging to mobilize them digitally. By crafting emotionally charged experiences, these movements extend their influence beyond virtual spaces and into the broader public sphere. Finally, this paper will reflect on the theological implications of these dynamics both on and offline. How do religious communicators in digital spaces reconcile their theological frameworks with the social impact of their communication? Can digital religious communities be harnessed to foster social cohesion and inclusivity instead of exacerbating social divisions? Through this lens, the paper seeks to deepen our understanding of the intersection between digital religion, political mobilization, and theological responsibility in the digital age. Full article

For the safety assessment of concrete dam–foundation systems, this study used an explicit time-stepping small-displacement algorithm, which simulates the hydromechanical interaction and considers the discrete representation of the foundation discontinuities. The proposed innovative methodology allows for the definition of more reliable safety factors and the identification of more realistic failure modes by integrating (i) softening-based constitutive laws that are closer to the real behavior identified experimentally in concrete–concrete and concrete–rock interfaces; (ii) a water height increase that can be considered in both hydraulic and mechanical models; and (iii) fracture propagation along the dam–foundation interface. Parametric studies were conducted to assess the impact of the mechanical properties on the global safety factors of three gravity dams with different heights. The results obtained using a coupled/fracture propagation model were compared with those from the strength reduction method and the overtopping scenario not considering the hydraulic pressure increase. The results show that the safety assessment should be conducted using the proposed methodology. It is shown that the concrete–rock interface should preferably have a high value of fracture energy or, ideally, higher tensile and cohesion strengths and high associated fracture energy. The results also indicate that with a brittle concrete–rock model, the predicted safety factors are always conservative when compared with those that consider the fracture energy. Full article

The relevant value standards for reserved deformation of tunnels with different types of loess soil are not yet perfect. Through mathematical statistics, literature research, and other methods, 148 monitoring sections of loess tunnels with different soil types were investigated. Pearson, Kendall, and Spearman correlation coefficients were used to analyze the influence of surrounding rock grade, moisture content, and burial depth on the deformation law of tunnels, providing reference for the value of reserved deformation for loess tunnels. The research results indicate that: (1) The correlation between soil type and convergence around the tunnel is strong, followed by excavation span, and the correlation between moisture content and burial depth is weak. Therefore, the design of reserved deformation should focus on considering the soil type and excavation span. (2) For loess tunnel sections with class IV surrounding rock, the deformation allowance for cohesive loess and silty loess tunnel sections can be set within 15 cm, and for sandy loess, it can be set within 15–20 cm. (3) For the loess tunnel section with V-grade surrounding rock, the deformation margin can be determined as follows: viscous loess within 15–20 cm, silty loess within 15 cm, and sandy loess within 35–47.5 cm. (4) The moisture content is mainly distributed between 11% and 23%. It is worth noting that in sandy loess sections, the influence of moisture content on tunnel arch settlement is more significant compared to cohesive loess and silty loess sections. (5) The settlement of the arch crown is affected by changes in coverage depth and has discreteness. When the deformation margin is set to 16 cm, the assurance rate can reach 84.6%. Finally, the rationality of the proposed reserved deformation amount was verified through engineering practice. The research results can provide reference for related similar projects. Full article

To investigate the dynamic wave propagation characteristics and dynamic response of heterogeneous layered slopes under a blasting vibration, a modeling method considering the slope’s layered dip angle and heterogeneity was proposed. Different dip jointed slope models were established using the Weibull random distribution function introduced to realize the stochastic distribution of rock mechanics parameters, representing heterogeneity. Taking the background project of the Sijiaying Yanshan Open-Pit Iron Mine as an example, through numerical simulation, the effects of different joint dip angles and rock hardness on the slope’s dynamic response were analyzed in detail. The sensitivity of the elastic modulus, cohesion, and friction angle to the slope dynamic response was also investigated. A comparative analysis of the amplification effects between a jointed slope and heterogeneous slope was conducted. Finally, the dynamic stability of the jointed slope and heterogeneous slope under a blasting load was analyzed. The results indicate that the Peak Ground Acceleration (PGA) of jointed slopes with dip angles of 45° and 60° is generally higher than that of slopes with a 0° dip angle and without joints. The smaller the rock mass heterogeneity, the smaller the PGA at the measuring points, and the less sensitive the PGA is to variations in the three quantities. Under the same physical and mechanical parameters of the rock, the amplification factor of jointed slopes is generally greater than that of heterogeneous slopes. Under the blasting load, the overall dynamic time-series safety factors of both slopes decrease first and then increase, with the safety factor reaching its lowest value at the location of the strongest blasting vibration wave. This study can provide guidance for the blasting design and safety protection of layered dip slopes and serve as a reference for the analysis of blasting impact laws in similar mines. Full article

This study analyzed the influence of the mechanical properties of two-step backfill on the stability of mining sites. The study focused on the one-step adhesive backfill of segmented backfill mining in a mine in Shandong Province, where the front wall was exposed and the back wall was compressed. A three-dimensional mechanical model of the front wall exposed, back wall compressed cemented filling material considering the mechanical properties of the two-step weakly cemented filling material was established through theoretical analysis. On this basis, considering the influence of different mechanical properties (elastic modulus, internal friction angle, cohesion, and Poisson’s ratio) of two-step weakly cemented filling on one-step cemented filling, FLAC 3D 6.00.60 numerical simulation software was used to study the influence of various factors on the horizontal displacement distribution of cemented filling under single-sided exposure conditions using numerical simulation methods. The results show that the adhesive filling material exposed on one side is subjected to lateral pressure from adjacent weak adhesive filling materials, and its stability is affected by the contact area and mechanical properties of the weak adhesive filling material. Increasing the elastic modulus of the two-step weak adhesive filling material from 100 MPa to 500 MPa can reduce the maximum horizontal displacement of the one-step adhesive filling material from 116 mm to 32 mm, a decrease of about 72%. Similarly, increasing the cohesive force from 0.09 MPa to 0.21 MPa can reduce displacement from 96 mm to 33 mm, a decrease of 66%. Improving the mechanical properties of the two-step weakly cemented filling material can reduce the tendency of tailings to slide and collapse, and can reduce the lateral pressure applied by the cemented filling material. The horizontal displacement law of the two-step cemented filling material with front wall exposure and rear wall compression is basically similar under different mechanical properties of the one-step weakly cemented filling material. In the vertical direction, as the height of the filling material increases, the horizontal displacement first slowly increases to the maximum value and then slowly decreases. As the mechanical properties of the two-step weakly cemented filling increase, the horizontal displacement of the one-step cemented filling decreases. Full article

A non-proportional reduction in strength parameters is widely used in slope stability assessment, but the current asynchronous reduction in strength parameters only considers the cohesion c and internal friction angle φ, which is suitable for slope stability assessment under static loads. Under seismic loads, however, tension at the rear edge of the slope often accompanies the appearance of ground cracks. In order to consider the relationship between tensile strength, cohesion, and the internal friction angle reduction coefficient, starting with the linear softening attenuation law of soil material strength parameters, a functional relationship between cohesion and internal friction angle is obtained. Then, considering that the failure of microelements in the tensile and shear zones conforms to the tension and shear of joint failure, the relationship between tensile strength, cohesion, and the internal friction angle reduction coefficient is derived. By establishing a homogeneous slope model and comparing and analyzing the progressive instability failure modes of slopes under static and seismic conditions, the stability and potential slip surface differences of slopes under two different working conditions are explored. The research results indicate that slope instability is a gradual, cumulative failure process under both static and dynamic conditions. The instability mode of the slope under static conditions is shear failure. In contrast, under dynamic loads, the instability failure of the slope is manifested as shear failure upward at the foot of the slope and tensile failure downward at the top of the slope. The stability coefficient of slopes under earthquake conditions is reduced by 17.3% compared to that under static conditions. Under earthquake conditions, the potential sliding surface under an asynchronous reduction in strength parameters is shallower than that under static conditions and deeper than that without an asynchronous reduction in strength parameters. Overall, the research results provide a reference for slope stability analysis and support design optimization under earthquake loads. Full article

The accurate calibration of snow parameters is necessary to establish an accurate simulation model of snow, which is generally used to study tire–snow interaction. In this paper, an innovative parameter inversion method based on in situ test results is proposed to calibrate the snow parameters, which avoids the damage to the mechanical properties of snow when making test samples using traditional test methods. A coupled Eulerian–Lagrangian (CEL) model of plate loading in snow was established; the sensitivity of snow parameters to the macroscopic load–sinkage relationship was studied; a plate-loading experiment was carried out; and the parameters of snow at the experimental site were inverted. The parameter inversion results from the snow model were verified by the experimental test results of different snow depths and different plate sizes. The results show the following: (1) The material cohesive, angle of friction, and hardening law of snow have great influence on the load–sinkage relationship of snow, the elastic modulus has a great influence on the unloading/reloading stiffness of snow, and the influence of density and Poisson’s ratio on the load–sinkage relationship can be ignored. (2) The correlation coefficient between the inversion result and the matching test data is 0.979, which is 0.304 higher than that of the initial inversion curve. (3) The load–sinkage relationship of snow with different snow depths and plate diameters was simulated by using the model parameter of inversion, and the results were compared with the experimental results. The minimum correlation coefficient was 0.87, indicating that the snow parameter inversion method in this paper can calibrate the snow parameters of the test site accurately. Full article

Among the most significant impacts related to the spread of settlements and the densification of urban areas, the reduction in the availability of public green spaces plays a central role in the definition of livable cities, in terms of the environment and social cohesion, interaction, and equality. In the framework of target 11.7 of the Sustainable Development Goals (SDG) 11, the United Nations has established the objective of ensuring universal, safe, and inclusive access to public spaces by 2030, for women, children, the elderly, and people with disabilities. This study proposes the evaluation of this objective for the urban area of the 14 Italian metropolitan cities, as defined by EUROSTAT and adopted by the United Nations and the Nature Restoration Law (NRL). A methodology based on open-source data and network analysis tools is tested for the provision of an unprecedented mapping of the availability and accessibility to green urban public spaces, which shows that less than 30% of metropolitan city residents have access to a green space within 300 m on foot, according to OpenStreetMap data (less than one in five for the Urban Atlas data). Furthermore, a critical analysis on the geometric and semantic definition of green urban public spaces adopted by the main European and international tools is carried out, which underlines the strategic role of crowdsourcing but also the need for mapping rules that make the data more consistent with the monitoring objectives set at the institutional level. Full article

In this paper, an investigation was conducted to characterize the behavior of weakly cohesive soil subjected to vibratory compaction. Thus, the authors developed a model for weakly cohesive soils, defined by inter-parametric laws that consider their initial state and predict the evolution of state parameters resulting from static and vibratory compaction processes, depending on the number of equipment passes. Four types of soil were proposed for testing, with different initial characteristics such as dry density, longitudinal modulus, and moisture content. Some correlations between main parameters involved in the compaction process were established, considering soil mechanical properties, compaction equipment, and in situ technology applied. The results obtained in the computational environment were implemented to predict the performance compaction process for an overall assessment. This research contributes to database development by offering valuable insights for specialists aiming to apply Industry 4.0 digitalization practices, which stipulate the use of predictability laws in pre-assessing the degree of soil compaction (or settlement) to estimate and maximize the efficiency of road construction or foundation works. These insights help optimize design processes, enhance functional performance, improve resource utilization, and ensure long-term sustainability in large infrastructure projects built on these soils. Full article

The establishment of the Ministry of Natural Resources and the Ministry of Agriculture and Rural Affairs of China marks the integrated installation of centralized and unified supervision of agricultural natural resource assets. It is of great practical significance to explore comprehensive systems of supervision of agricultural natural resource assets with the aim of super-ministry system restructuring; this could provide support for the development of new quality agricultural productivity. This paper mainly discusses the value objective and the approach of the rule of law concerning comprehensive supervision of agricultural natural resource assets in China with the aim of super-ministry system restructuring and codification. It combines a normative analysis of law with an economic analysis to address the current laws and regulations concerning the supervision of agricultural natural resource assets and summarize the existing problems of the supervision system. From the perspective of game equilibrium, the paper explores the reasonable expected utility of multiple entities under comprehensive supervision of agricultural natural resource assets. The results show the following: (1) The value objective of comprehensive supervision of agricultural natural resource assets should include process-oriented, multi-participation asset accretion and technological innovation. (2) Different supervision departments have different objectives and interests with respect to taking risks. (3) From the perspective of game equilibrium, an effective balance between development and use and comprehensive supervision of agricultural natural resource assets calls for a reconstruction of the structure of rights (powers) and for practical systematic selection. Therefore, this research recommends that efforts to improve the legal systems of comprehensive supervision of agricultural natural resource assets in China should take comprehensive supervision legislation as an approach to solving the issues and should also take comprehensive central and local cohesion as realization mechanisms, highly integrated and coordinated in legislation, while allocating to various institutions responsibility for the efficient use of agricultural natural resource assets, and the protection of rural green ecological environment, to promote the revitalization of rural ecology, and the security of agricultural resources. Full article