Abstract This study investigates the mechanical performance of slag placed over subgrade soil, with a focus on the reinforcing role of woven geotextiles under cyclic loading. To achieve this, two complementary experimental approaches were employed: large-scale box tests simulating repeated traffic loads with a peak load of 20 kN applied over 100,000 cycles and resilient modulus ( M R ) tests conducted in accordance with AASHTO T 307. Results showed that the inclusion of a woven geotextile layer substantially enhanced both the permanent deformation and resilient behavior of the combined slag–subgrade system. In the large-scale tests, geotextile reinforcement reduced permanent deformation beneath the loading plate by 70.5%, compared to the unreinforced case. Similar improvements were observed around the loading plate, indicating enhanced lateral confinement. Stress–strain responses confirmed stabilized behavior in the reinforced sections, free from peak stress surges and instability. Furthermore, resilient modulus results demonstrated a consistent increase in M R values across all stress stages, confirming improved recoverability and stiffness under repeated loading. Overall, the combined findings reveal that the utilized geotextile reinforcement effectively suppresses plastic deformation while improving the resilient performance of granular layers, underscoring its potential as a structurally reliable solution for pavement base systems incorporating slag.
In this paper, a new numerical scheme for optimal control of jump-diffusion model is proposed by using stohastic Runge-Kutta (SRK) method. After discretizing the problem with the SRK method, optimality conditions are obtained by using the discretize-then-optimize approach. It is shown that the constructed numerical scheme is similar to the continuous optimality conditions obtained by using the Hamilton-Jacobi-Bellman equations. Moreover, a numerical scheme for control problems of Ornstein-Uhlenbeck (OU) with jump is presented as a simple version of jump diffusion equations. Some numerical examples are chosen to show the efficiency of the theoretical results.
Abstract This study examines whether wall material, hollow concrete block or solid clay brick, was associated with collapse-related failure in 516 nonengineered legacy rural masonry buildings in Antakya, Hatay, after the 2023 Kahramanmaraş earthquake sequence. Damage states were grouped into binary Failure and Nonfailure classes within a spatially constrained observational comparison. Because nonfailure outcomes were sparse, Firth penalized logistic regression was applied to reduce small-sample bias. The overall failure rate was 89.9% (95% confidence interval (CI) = 87.0%–92.2%). Solid brick buildings showed a higher observed failure rate (96.4%) than hollow block buildings (89.2%), but the association was not statistically significant [odds ratio (OR) = 2.56; 95% profile-penalized-likelihood interval = 0.83–12.66; p = 0.109 ]; building height was likewise nonsignificant (OR = 1.16; p = 0.746 ). Adjustment for construction period and neighborhood gave a similar material estimate (OR = 2.47; p = 0.134 ), whereas neighborhood showed the strongest recorded association with failure ( p < 0.001 ), with failure rates of 78.9% to 96.0% across three adjacent neighborhoods. A design-based simulation indicated limited detection probability; the data therefore neither demonstrates nor excludes a material effect. System-level features were not recorded as building-level variables. Wall material alone is insufficient as a standalone screening criterion.
This paper presents a model for energy conversion and derives an exergy balance equation for single-step chemical reactions in flames. The model can evaluate changes in chemical and thermodynamic energy, the loss of available energy, and thermodynamic efficiency. By combining this model with a detailed chemical mechanism, the effects of pressure, temperature, and the equivalence ratio on exergy efficiency are evaluated. In addition, important chemical reactions and substances for energy conversion can be identified. Furthermore, this model is applied to the thermodynamic analysis of an inverse-diffusion ethylene (C2H4) flame. A systematic study, including entropy generation, chemical analysis, and exergy analysis, is carried out. The combustion and thermodynamic characteristics of the inverse-diffusion C2H4 flame are investigated. The results indicate that increasing the temperature of the medium is a relatively direct and effective way to improve exergy efficiency. The pyrolysis and oxidation of C2H4 are the main sources of the chemical entropy generation rate (EGR), while multi-carbon reactions contribute very little. The pathways C2H4 -> C2H3 -> CH2 -> (CH2O or CH) -> HCO -> CO are the most important for the chemical EGR. From the inner to the front of the flame, thermodynamic equilibrium is established, and a low temperature is a more significant factor limiting reactions than reactant concentration. Five reactions (R12, R48, R60, R77, and R55) determine the energy conversion efficiency of the entire flame. These reactions account for more than 95 % of energy conversion and should be emphasised when optimising combustion.
The manufacturing of Ti6Al4V sheet metal components for aerospace applications is strongly limited by the poor formability of the alloy at room temperature, making conventional cold forming techniques unsuitable for manufacturing such components. To overcome these limitations, hot stamping techniques based on controlled thermo-mechanical conditions have been developed to enable the production of sheet metal parts with moderately complex geometries. This paper presents a comprehensive review of hot stamping processes operating at quasi-static strain rate (10−3 –10−1 s−1) within the warm temperature regime (0.3Tm – 0.5Tm), aiming to clarify process regimes, deformation mechanisms, and current technological limitations. Particular attention is given to the influence of key process parameters such as temperature, stamping velocity, and applied load on deformation behavior, microstructure evolution and mechanical performance. In addition, numerical modeling approaches based on finite element analysis are critically reviewed, including comparisons of material models, formability criteria, friction modeling, and thermo-mechanical coupling strategies employed in commercial simulation software. Lastly, the formation of alpha case, oxidation phenomena, and the subsequent pickling processes involved in the manufacturing of Ti6Al4V sheet metal components are discussed. Based on the reviewed literature, the advantages and limitations of different hot stamping techniques are compared, and practical tables are proposed to support efficient, sustainable, repeatable, and controllable process selection. Moreover, current research gaps are identified, particularly regarding tool lifespan, combined effects of hot stamping variables (temperature, stamping velocity and applied load) on formability, and the integration of microstructure-based simulation models, outlining directions for further investigation.
