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At this moment, there is substantial anxiety surrounding the fire safety of huge reinforced concrete (RC) constructions. The limitations enforced by test facilities, technology, and high costs have significantly limited both full-scale and scaled-down structural fire experiments. The behavior of an individual structural component can have an impact on the entire structural system when it is connected to it. This paper addresses the development and testing of a self-straining preloading setup that is used to perform thermomechanical action in RC beams and slabs.

Thermomechanical action is a combination of both structural loads and a high-temperature effect. Buildings undergo thermomechanical action when it is exposed to fire. RC beams and slabs are one of the predominant structural members. The conventional method of testing the beams and slabs under high temperatures will be performed by heating the specimens separately under the desired temperature, and then mechanical loading will be performed. This gives the residual strength of the beams and slabs under high temperatures. This method does not show the real-time behavior of the element under fire. In real-time, a fire occurs simultaneously when the structure is subjected to desired loads and this condition is called thermomechanical action. To satisfy this condition, a unique self-training test setup was prepared. The setup is based on the concept of a prestressing condition where the load is applied through the bolts.

To validate the test setup, two RC beams and slabs were used. The test setup was tested in service load range and a temperature of 300 °C. One of the beams and slabs was tested conventionally with four-point bending and point loading on the slab, and another beam and slab were tested using the preloading setup. The results indicate the successful operation of the developed self-strain preloading setup under thermomechanical action.

Gaining insight into the unpredictable reaction of structural systems to fire is crucial for designing resilient structures that can withstand disasters. However, comprehending the instantaneous behavior might be a daunting undertaking as it necessitates extensive testing resources. Therefore, a thorough quantitative and qualitative numerical analysis could effectively evaluate the significance of this research.

The study was performed to validate the thermomechanical load setup for beams and slabs on a single-bay single-storey RC frame with and without slab under various fire possible scenarios. The thermomechanical load setup for RC members is found to be scarce.

The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely researched and rapidly developed biodegradable copolyester. In a tensile test, we found that the fractured PBAT samples had a heat-driven shape memory effect which piqued our interest, and it will lay a foundation for the application of PBAT in new fields (such as heat shrinkable film).

The shape memory effect of PBAT and the effect of the thermomechanical condition on its shape memory property were confirmed and systematically investigated by a thermal mechanical analyzer and tensile machine.

The results showed that the PBAT film had broad shape memory transform temperature and exhibited excellent thermomechanical stability and shape memory properties. The shape memory fixity ratio (Rf) of the PBAT films was increased with the prestrain temperature and prestrain, where the highest Rf exceeded 90%. The shape memory recovery ratio (Rr) of the PBAT films was increased with the shape memory recovery temperature and decreased with the prestrain value, and the highest Rr was almost 100%. Moreover, the PBAT films had high shape memory recovery stress which increased with the prestrain value and decreased with the prestrain temperature, and the highest shape memory recovery stress can reach 7.73 MPa.

The results showed that PBAT had a broad shape memory transform temperature, exhibited excellent thermomechanical stability and shape memory performance, especially for the sample programmed at high temperature and had a larger prestrian, which will provide a reference for the design, processing and application of PBAT-based heat shrinkable film and smart materials.

This study confirmed and systematically investigated the shape memory effect of PBAT and the effect of the thermomechanical condition on the shape memory property of PBAT.

In a printed circuit board assembly (PCBA), the coefficient of thermal expansion (CTE) mismatch between the solder joint materials has a detrimental impact on reliability. The mechanical stresses caused by the thermal changes of the assembly lead to fatigue and sometimes the failure of the solder joints. The purpose of this study is to propose a novel pad design to obtain an interrupted solder/substrate interface, to improve the PCBA reliability.

An interruption in the continuous intermetallic compound (IMC) layer of a solder joint was implemented, by the deposition of a silicone film in the pad, changing its geometry. That change allows a redistribution of stresses in the most ductile zone of the solder joint, the solder. The stress concentration at the solder/substrate interface is reduced, as well as the general state of stress at the solder joint.

A new way was developed to reduce the stress on the solder joints, caused by thermal variations, because of the different components CTEs mismatch. This new method consists of interrupting the IMC layers of the solder joint, strategically, redirecting the usual stresses to a more ductile area of the joint, the solder. This is an innovative method that allows increase the lifetime of PCBAs and the equipments.

In this study, a new pad design concept for higher solder joint reliability was developed to reduce the shear stress in the solder joints because of the CTE mismatch between all the solder joint components.

This study aims to investigate the relationship between material properties and alloying elements of carbon steels through predictive modeling. Aircraft control cables are usually made of steel materials and subjected to deformation because of the motion of control surfaces such as aileron, rudder, elevator and trailing edge flaps. Investigation of the relationship between material properties and alloying elements would therefore be explored.

This study is focused on the modeling of mechanical properties of carbon steels concerning the content of alloying elements by using response surface methodology with false discovery rate (FDR) correction approach. SAS Institute JMP data analysis software was used to develop response and argument relationships in various carbon steels without including thermomechanical treatment effect. Mechanical properties were considered as tensile strength, yield strength, ductility, and Brinell hardness. Carbon (0.28 Wt.%-0.46 Wt.%) and manganese (0.7 Wt.%-0.9 Wt.%) proportions were gathered from ASM Handbook. Linear regression models were tested for the statistical adequacy by using analysis of variance and statistical significance analysis. A posterior probability, which refers to Benjamini–Hochberg FDR (BH-FDR), was embedded as multiple testing corrections of the t-test p-values.

Predictive modeling of the material properties for aircraft control cables was successfully achieved by using the response surface method with BH-FDR significance level of 0.05.

The effect of statistically developed graphical interactions of alloying elements on the common mechanical properties of such steels would provide prompt comparison to material suppliers and part manufacturers except those subjected to thermomechanical treatment applications.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

Blade tip clearance has always been a concern for the gas turbine design and control. The numerical analysis of tip clearance is based on the turbine components displacement. The purpose of this paper is to investigate the thermal and mechanical effects on a real cooling blade rather than the simplified model.

The coupled fluid-solid method is used. The thermal analysis involves solid and fluid domains. The distributions of blade temperature, stress and displacement have been calculated numerically under real turbine operating conditions.

Temperature contour can provide a reference for stress analysis. The results show that temperature gradient is the main source of solid stress and radial displacement. Compared with thermal or mechanical effect, there is a great change of stress magnitude for the thermomechanical effect. Large stress gradients are found between the leading and trailing edge of turbine cooling blade. Also, the blade radial displacement is mainly attributed to the thermal load rather than the centrifugal force. The analysis of the practical three-dimensional model has achieved the more precise results.

It is significant for clearance design and life prediction.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

The purpose of this paper is to present an analysis of the effect of the temperature on the creep deformation during vertical well drilling in salt rocks in selected cases.

The authors performed numerical simulations by Finite Element Method, using non-linear viscoelastic models and weak thermomechanical coupling. The authors evaluated, in selected cases, the effect of temperature during salt rock vertical well drilling. Numerical examples were performed to validate the studies. More specifically, the authors considered the problem of vertical well drilling for oil exploration below these salt layers.

The authors concluded that the biggest reduction in the wellbore closure rate occurs when the wellbore is at low temperature with respect to the rock initial. This is due to two factors, namely, a reduced salt viscous strain rate and the thermal strain contrary to the well radial closure caused by the temperature variation. Beyond the creep effect, the thermal strain also affects the stress in the creep constitutive equation.

With recent oil discoveries in deep water, for example, in the pre-salt, where temperatures are high, the study of the influence of temperature is important, since it contributes to the increase of the creep. The results here presented are relevant, although the engineering aspects of a practical solution for reducing the wellbore displacement based on temperature variation is challenging. Such approach requires cooling mechanisms that delay the heating of the drilling fluid, which is surrounded by rocks at high temperature.

The main contribution of this paper is to present a numerical study, in selected cases, of the effect of temperature on the creep deformation during vertical well drilling in salt rocks, analyzing a possible reduction of these deformations when subjected to a temperature variation.

Fibers and fabrics are often used to reinforce shape memory polymers (SMPs) to improve their mechanical strength and properties, and the composites have been widely used in engineering. However incorporation of fibers and fabrics in SMPs are often accompanied with the degradation of thermal mechanical properties and shape memory effect. The thermomechanical properties and degradation mechanisms of a shape-memory polymer composite (SMPC) were investigated. Up to 100% extension, the SMPCs showed good shape memory effect with excellent recovery ratio, recovery stress and mechanical properties; while beyond that the recovery ratio and stress of the composites deteriorate rapidly due to the significant delamination and debonding of fibers and fabrics from the SMP resin and accumulation of broken fibers.