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The purpose of this paper is to provide a method to predict the situation of a loaded element in the compressive stress curve to prevent failure of crucial elements in load-bearing masonry walls and to propose a material model to simulate a compressive element successfully in Abaqus software to study the structural safety by using non-linear finite element analysis.

A Weibull distribution function was rewritten to relate between failure probability function and axial strain during uniaxial compressive loading. Weibull distribution parameters (shape and scale parameters) were defined by detected acoustic emission (AE) events with a linear regression. It was shown that the shape parameter of Weibull distribution was able to illustrate the effects of the added fibers on increasing or decreasing the specimens’ brittleness. Since both Weibull function and compressive stress are functions of compressive strain, a relation between compressive stress and normalized cumulative AE hits was calculated when the compressive strain was available. By suggested procedures, it was possible to monitor pretested plain or random distributed short fibers reinforced adobe elements (with AE sensor and strain detector) in a masonry building under uniaxial compression loading to predict the situation of element in the compressive stress‒strain curve, hence predicting the time to element collapse by an AE sensor and a strain detector. In the predicted compressive stress‒strain curve, the peak stress and its corresponding strain, the stress and strain point with maximum elastic modulus and the maximum elastic modulus were predicted successfully. With a proposed material model, it was illustrated that the needed parameters for simulating a specimen in Abaqus software with concrete damage plasticity were peak stress and its corresponding strain, the stress and strain point with maximum elastic modulus and the maximum elastic modulus.

The AE cumulative hits versus strain plots corresponding to the stress‒strain curves can be divided into four stages: inactivity period, discontinuous growth period, continuous growth period and constant period, which can predict the densifying, linear, non-linear and residual stress part of the stress‒strain relationship. By supposing that the relation between cumulative AE hits and compressive strain complies with a Weibull distribution function, a linear analysis was conducted to calibrate the parameters of Weibull distribution by AE cumulative hits for predicting the failure probability as a function of compressive strain. Parameters of m and θ were able to predict the brittleness of the plain and tire fibers reinforced adobe elements successfully. The calibrated failure probability function showed sufficient representation of the cumulative AE hit curve. A mathematical model for the stress–strain relationship prediction of the specimens after detecting the first AE hit was developed by the relationship between compressive stress versus the Weibull failure probability function, which was validated against the experimental data and gave good predictions for both plain and short fibers reinforced adobe specimens. Then, the authors were able to monitor and predict the situation of an element in the compressive stress‒strain curve, hence predicting the time to its collapse for pretested plain or random distributed short fibers reinforced adobe (with AE sensor and strain detector) in a masonry building under uniaxial compression loading by an AE sensor and a strain detector. The proposed model was successfully able to predict the main mechanical properties of different adobe specimens which are necessary for material modeling with concrete damage plasticity in Abaqus. These properties include peak compressive strength and its corresponding axial strain, the compressive strength and its corresponding axial strain at the point with maximum compressive Young’s modulus and the maximum compressive Young’s modulus.

The authors were not able to decide about the effects of the specimens’ shape, as only cubic specimens were chosen; by testing different shape and different size specimens, the authors would be able to generalize the results.

The paper includes implications for monitoring techniques and predicting the time to the collapse of pretested elements (with AE sensor and strain detector) in a masonry structure.

This paper proposes a new method to monitor and predict the situation of a loaded element in the compressive stress‒strain curve, hence predicting the time to its collapse for pretested plain or random distributed short fibers reinforced adobe (with AE sensor and strain detector) in a masonry building under uniaxial compression load by an AE sensor and a strain detector.

The purpose of this paper is to present an improved temperature-dependent constitutive model for steel that accounts for local instabilities of slender plates using an effective stress-based method. This model can be easily implemented for use with Bernoulli beam finite elements (FEs) in the fire situation.

The constitutive model is derived by calibration on parametric numerical analysis on isolated plates subject to buckling at different elevated temperatures. The model is implemented in the FE software SAFIR and validation is performed against experimental and shell element analysis results.

A constitutive model based on an equivalent stress method is proposed as an efficient way to consider local buckling in steel members exposed to fire. The proposed stress–strain–temperature relationship is asymmetric and is modified in compression only, by reducing the proportional limit, the yield stress and the strain at yield stress. The reduction of these parameters depends on the plate’s boundary conditions, slenderness and temperature. The validation of the proposed model shows good agreement over a range of profile dimensions, temperatures and steel grades.

The model is still giving conservative results for large compressive load eccentricities. An enhanced model is under development to improve the predictive capability under large eccentricities.

The proposed model, easily implemented into any finite element software, allows using fibre type (Bernoulli) beam FEs for modelling structures made of slender sections. This has major practical implications as beam elements are the workhorse used for simulating the behaviour of structures in fire. This model, thus makes it possible to simulate large structures with slender steel sections at a limited computational cost.

The paper presents a novel steel constitutive model based on an innovative approach to capture local buckling at the material level using an equivalent stress approach. The theoretical development, validation and perspectives for future improvements are presented.

The purpose of this paper is to obtain the mechanical behavior and damage mechanism of the coal and rock near the stope under the stress state and stress paths of the surrounding rock with the dynamic mining.

Through the three-axial compression test and the uniaxial compression test by meso experiment device, the mechanical behavior and fracture evolution process of coal and rock were studied, and the acoustic emission (AE) characteristics under uniaxial compression of the coal and rock were contrasted.

Under the three-axial compression, the strength of coal and rock enhance significantly by confining pressure. The volume of outburst coal shows obvious stages: compression is followed by expansion. The coal first appear to undergo compaction under vertical stress due to volume decrease, but with the development of micro- and macro-cracks, the specimens appeared to expand; under the uniaxial compression, through the comparison of stress–strain relationship and the crack propagation process, stress drop and fracture of coal have obvious correlation. The destruction of coal was gradual due to the slow and steady accumulation of internal damage. Due to the influence of the end effect, the specimens show the “conjugate double shear failure”. The failure process of the coal and rock and the characteristics of the AEs have a corresponding relationship: the failure causes a large number of AE events. Before the events peak, there was an initial stage, calm growth stage and explosive growth stage. There were some differences between the rock and coal in the characteristics of the AE.

These research studies are conducted to provide guidance on the basis of mine disaster prevention and control.

Towards the end of the twentieth century, the world has witnessed an amazing economic take‐off in the East Asia, especially within the territory of so‐called “Greater China”, encompassing the PRC and Taiwan. Against this economic and cultural background, this study surveyed 258 and 189 employees respectively in Taiwan, and the PRC (Shanghai), to examine generalizability of a generic work‐stress model to the Chinese societies. It further examined the sub‐cultural differences in the work‐stress processes, by drawing contrast of the PRC and Taiwan. In addition, roles of emic constructs of Chinese primary and secondary control beliefs were also examined. Results showed that the generic work‐stress model could be reasonably applied to Chinese urban work contexts in the PRC and Taiwan. Work stress related as expected to strain effects. At a more refined sub‐cultural level, it was found that different sources of work stress became salient contributors to strain outcomes in the PRC and Taiwan. These differences reflect the diverse political, social, and economic characteristics of the two Chinese societies. More importantly, emic constructs of Chinese control beliefs were found to have rather consistent direct effects on strain outcomes. However, indirect (moderating) effects of control beliefs were not strong and inconsistent.

The paper reviews the application of the finite element method to the analysis of large‐deflection elasto‐plastic behaviour and traces the development of such a solution for plated structures. The accuracy of the approach is established by many comparisons with available solutions for isolated plates and conclusions are drawn on suitable idealizations for plated structures. The results of an analysis of a typical plate girder, allowing fully for the interaction between the component plates, are presented. Comparisons with experimentally measured values for the girder confirm the validity of the proposed approach for the study of the collapse modes of plated structures. The need for expensive experimentation is thereby reduced.

PLASTIC buckling of plates and shells has been worked out by Bijlaard, Ilyushin, Stowell, Handelman and Prager, Gerard and others. Some investigators have assumed deformation type stress‐strain laws while others have used incremental type (flow type) stress‐strain laws. The present work is an extension of the work started by Gerard along the lines initiated by Stowell.

In microfluidic channel fabrication in low temperature co‐fired ceramics (LTCC), one of the biggest challenges is the elimination of channel deformation during lamination. The purpose of this paper is to describe the expected deformation of the substrate and the sacrificial layer (starch powder and 3D printed UV polymerized material) during the lamination process of microfluidic structure fabrication.

Uniaxial compression and Jenike shear test were used to obtain the mechanical parameters of starch sacrificial volume material (SVM). To determine the stress‐strain characteristics of LTCC a uniaxial compression experiment was conducted. The shape of the laminated LTCC containing embedded channel was modeled by finite element method using the mechanical parameters obtained by the measurements.

It was found that the choice of SVM plays an important role in channel deformation. A design rule is given considering the channel width and the choice of SVM based on the simulation results.

Until now the lamination step of LTCC technology was only optimized in an empirical way.

The fracture mechanism of S-07 steel was investigated by observing the fracture surface of the specimens with scanning electron microscope (SEM). Furthermore, the overall elastic–plastic behaviors and the stress state evolution during the loading procedure of all specimens were simulated by FE analysis to obtain the local strain at crack nucleated location and the average triaxiality of each type of specimen.

Three types of tests under various stress states were performed to study the ductile fracture characteristics of S-07 high strength steel in quasi-static condition.

Under tensile and torsion loading conditions, S-07 steel exhibits two distinctive rupture mechanisms: the growth and internal necking of voids governs the rupture mechanism in tension dominated loading mode, while the change of void shape and internal shearing in the ligaments between voids dominants for shear conditions.

The failure criterion for S-07 steel considering the influence of the triaxial stress state was established.

This study aims to characterize the mechanical properties of sintered nano-silver under various sintering processes by nano-indentation tests.

Through microstructure observations and characterization, the influences of sintering process on the microstructure evolutions of sintered nano-silver were presented. And, the indentation load, indentation displacement curves of sintered silver under various sintering processes were measured by using nano-indentation test. Based on the nano-indentation test, a reverse analysis of the finite element calculation was used to determine the yielding stress and hardening exponent.

The porosity decreases with the increase of the sintering temperature, while the average particle size of sintered nano-silver increases with the increase of sintering temperature and sintering time. In addition, the porosity reduced from 34.88%, 30.52%, to 25.04% if the ramp rate was decreased from 25°C/min, 15°C/min, to 5°C/min, respectively. The particle size appears more frequently within 1 µm and 2 µm under the lower ramp rate. With reverse analysis, the strain hardening exponent gradually heightened with the increase of temperature, while the yielding stress value decreased significantly with the increase of temperature. When the sintering time increased, the strain hardening exponent increased slightly.

The mechanical properties of sintered nano-silver under different sintering processes are clearly understood.

This paper could provide a novel perspective on understanding the sintering process effects on the mechanical properties of sintered nano-silver.

An overview of the mechanical behaviour of common solder types is presented, with particular emphasis placed upon those properties relevant to the performance of soldered joints in service. The requirements for more sophisticated and complex information are highlighted in order to assist design for the increasingly arduous demands associated with miniaturisation.