Search published articles


Showing 2 results for Memory Alloy

Hamidreza Ashrafi, Peyman Beiranvand,
Volume 1, Issue 1 (9-2017)
Abstract

The effect of shape memory and super-elastic property are two exclusive features in shape memory alloys. In order to exploit the properties of shape memory effect, alloy needs to be heated but super-elastic property in these alloys will be proposed automatically in case suitable conditions. In case of using shape memory alloys as Longitudinal armatures in reinforced concrete structures considering them buried in concrete, exploitation of shape memory property will have its particular problems that these problems won’t happen about super-elastic property. Considering the high rate of strain capacity 3% to 8% in memory alloys with super-elastic behavior and the limitation of this capacity in concrete, conditions are necessary to be prepared in a way that memory alloy has the opportunity to propose super-elastic property. In this study, with simulating short-square reinforced concrete column experimental model in software ANSYS and in multi-level and increasing process, longitudinal armatures with shape memory alloy material will replace steel armatures with super-elastic behavior will be investigated with making shape memory alloy kind as variable (Copper and nickel-based alloys), the opportunity of super-elastic property emergence in these alloys and with playing the role of longitudinal armature in reinforced concrete column.

Ahmad Maleki, Babak Baradar Ayari Khosroshahi,
Volume 3, Issue 1 (6-2019)
Abstract

In today's world, with the rapid advancement of science and technology, new materials are emerging every day, in which alloys of memory are a form of these materials. Since the use of the frame system with conventional bracing is not responsive to structural requirements due to limitations such as low wear ability, buckling bracing in the pressure and reducing load capacity, so the use of this type of alloy in brackets can be a breakthrough. In this research, the effect of braces with intelligent memory alloys on energy dissipation and steel frame formation is investigated by modeling in ABAQUS finite element software. The braiding function is modeled in several modes: braiding consisting of steel, memory alloy, memory alloy and steel along the length and cross section of the bracket with different sizes in the form of 7 numerical models in Abaqus software and their results are compared. In two models, one of which has only memory-alloy materials and the other steel materials, the analysis of the results showed that the final weight of the braiding material is about 16% more than the bracelet with alloys of memory. Also, the initial hardness and maximum stress and energy consumption are higher than the steel model. In models that use a combination of two compositions of memory alloy and steel in a cross-sectional curtain (in different ratios), reducing the steel's percentage has a very small effect on reducing the final load and the energy consumption of the bracing. The results showed that the initial stiffness and energy consumption of the two models are approximately equal to those of the curtain that had 50% of the cross-sectional length and the bracelet length of the steel and the rest of the memory alloy. But the final load and the stress of a model in which two materials in the cross-sectional area are 18 KN and 115 Mpa, respectively.


Page 1 from 1