Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 8 of 8

Full-Text Articles in Engineering

The Effect Of Fine And Coarse Recycled Aggregates On Fresh And Mechanical Properties Of Self-Compacting Concrete, Mahmoud Nili, Hossein Sasanipour, Farhad Aslani Apr 2019

The Effect Of Fine And Coarse Recycled Aggregates On Fresh And Mechanical Properties Of Self-Compacting Concrete, Mahmoud Nili, Hossein Sasanipour, Farhad Aslani

Research outputs 2014 to 2021

Today, the use of recycled aggregates as a substitute for a part of the natural aggregates in concrete production is increasing. This approach is essential because the resources for natural aggregates are decreasing in the world. In the present study, the effects of recycled concrete aggregates as a partial replacement for fine (by 50%) and coarse aggregates (by 100%) were examined in the self-compacting concrete mixtures which contain air-entraining agents and silica fumes. Two series of self-compacting concrete mixes have been prepared. In the first series, fine and coarse recycled mixtures respectively with 50% and 100% replacement with air entraining …


Development Of Heavyweight Self-Compacting Concrete And Ambient-Cured Heavyweight Geopolymer Concrete Using Magnetite Aggregates, Afsaneh Valizadeh, Farhad Aslani, Zohaib Asif, Matt Roso Mar 2019

Development Of Heavyweight Self-Compacting Concrete And Ambient-Cured Heavyweight Geopolymer Concrete Using Magnetite Aggregates, Afsaneh Valizadeh, Farhad Aslani, Zohaib Asif, Matt Roso

Research outputs 2014 to 2021

Heavyweight self-compacting concrete (HWSCC) and heavyweight geopolymer concrete (HWGC) are new types of concrete that integrate the advantages of heavyweight concrete (HWC) with self-compacting concrete (SCC) and geopolymer concrete (GC), respectively. The replacement of natural coarse aggregates with magnetite aggregates in control SCC and control GC at volume ratios of 50%, 75%, and 100% was considered in this study to obtain heavyweight concrete classifications, according to British standards, which provide proper protection from sources that emit harmful radiations in medical and nuclear industries and may also be used in many offshore structures. The main aim of this study is to …


Fire Performance Of Heavyweight Self-Compacting Concrete And Heavyweight High Strength Concrete, Farhad Aslani, Fatemeh Hamidi, Qilong Ma Jan 2019

Fire Performance Of Heavyweight Self-Compacting Concrete And Heavyweight High Strength Concrete, Farhad Aslani, Fatemeh Hamidi, Qilong Ma

Research outputs 2014 to 2021

In this study, the fresh and hardened state properties of heavyweight self-compacting concrete (HWSCC) and heavyweight high strength concrete (HWHSC) containing heavyweight magnetite aggregate with 50, 75, and 100% replacement ratio, and their performance at elevated temperatures were explored experimentally. For fresh-state properties, the flowability and passing ability of HWSCCs were assessed by using slump flow, T500 mm, and J-ring tests. Hardened-state properties including hardened density, compressive strength, and modulus of elasticity were evaluated after 28 days of mixing. High-temperature tests were also performed to study the mass loss, spalling of HWSCC and HWHSC, and residual mechanical properties at 100, …


Properties Of Ambient-Cured Normal And Heavyweight Geopolymer Concrete Exposed To High Temperatures, Farhad Aslani, Zohaib Asif Jan 2019

Properties Of Ambient-Cured Normal And Heavyweight Geopolymer Concrete Exposed To High Temperatures, Farhad Aslani, Zohaib Asif

Research outputs 2014 to 2021

Ambient-cured heavyweight geopolymer concrete (HWGC) is a new type of concrete that combines the benefits of both heavyweight concrete (HWC) and geopolymer concrete (GC). HWGC provides proper protection from the sources that emit harmful radiations in medical and nuclear industries. Furthermore, HWGC may also be used in offshore structures for pipeline ballasting and similar underwater structures. In this study, heavyweight aggregates (magnetite) have been used and replaced by normal-weight coarse aggregates in GC at volume ratios of 50, 75, and 100% to attain heavyweight classification according to British standards. This study investigates the impacts of high temperatures on standard ambient-cured …


Beta-Type Ti-Nb-Zr-Cr Alloys With Large Plasticity And Significant Strain Hardening, Syed F. Jawed, Chirag D. Rabadia, Y. J. Liu, L. Q. Wang, Y. H. Li, X. H. Zang, Laichang C. Zhang Jan 2019

Beta-Type Ti-Nb-Zr-Cr Alloys With Large Plasticity And Significant Strain Hardening, Syed F. Jawed, Chirag D. Rabadia, Y. J. Liu, L. Q. Wang, Y. H. Li, X. H. Zang, Laichang C. Zhang

Research outputs 2014 to 2021

A series of Ti-25Nb-8Zr-xCr (x = 0, 2, 4, 6, 8 wt%) alloys were designed based on DV-Xα cluster method and e=a-Δr diagram with an anticipation to obtain high plasticity and significant strain hardening. The designed alloys were produced through cold crucible levitation melting technique in order to effectively investigate their micro-structures and mechanical properties. The addition of Cr significantly enhances the β stability in the microstructures of the Ti-25Nb-8Zr-xCr alloys. Both yield strength and hardness of the studied alloys increase due to the effect of solid-solution strengthening. By contrast, the plasticity, maximum strength and strain hardening rate are influenced …


Processing Of Al-12si-Tnm Composites By Selective Laser Melting And Evaluation Of Compressive And Wear Properties, Konda Prashanth, Sergio Scudino, Anil Chaubey, Lukas Löber, Pei Wang, Hooyar Attar, Frank Schimansky, Florian Pyczak, Jürgen Eckert Jan 2016

Processing Of Al-12si-Tnm Composites By Selective Laser Melting And Evaluation Of Compressive And Wear Properties, Konda Prashanth, Sergio Scudino, Anil Chaubey, Lukas Löber, Pei Wang, Hooyar Attar, Frank Schimansky, Florian Pyczak, Jürgen Eckert

Research outputs 2014 to 2021

Al-12Si (80 vol%)-Ti52.4Al42.2Nb4.4Mo0.9B0.06 (at.%) (TNM) composites were successfully produced by the selective laser melting (SLM). Detailed structural and microstructural analysis shows the formation of the Al6MoTi intermetallic phase due to the reaction of the TNM reinforcement with the Al-12Si matrix during SLM. Compression tests reveal that the composites exhibit significantly improved properties (∼140 and ∼160 MPa higher yield and ultimate compressive strengths, respectively) compared with the Al-12Si matrix. However, the samples break at ∼6% total strain under compression, thus showing a reduced plasticity of the composites. Sliding wear tests were carried out for both the Al-12Si matrix and the Al-12Si-TNM …


Utilisation Of Iron Ore Tailings As Aggregates In Concrete, Francis Atta Kuranchie, Sanjay Kumar Shukla, Daryoush Habibi, Alireza Mohyeddin Jan 2015

Utilisation Of Iron Ore Tailings As Aggregates In Concrete, Francis Atta Kuranchie, Sanjay Kumar Shukla, Daryoush Habibi, Alireza Mohyeddin

Research outputs 2014 to 2021

Sustainable handling of iron ore tailings is of prime concern to all stakeholders who are into iron ore mining. This study seeks to add value to the tailings by utilising them as a replacement for aggregates in concrete. A concrete mix of grade 40 MPa was prepared in the laboratory with water–cement ratio of 0.5. The concrete were cured for 1, 2, 3, 7, 14 and 28 days. The properties of the concrete such as workability, durability, density, compressive strength and indirect tensile strength were tested. A controlled mix of concrete was also prepared in similar way using conventional materials …


Synergistic Toughening Of Hard, Nacre-Mimetic Mosi2 Coatings By Self-Assembled Hierarchical Structure, Jiang Xu, Xiaoli Zhao, Paul Munroe, Zonghan Xie Jan 2014

Synergistic Toughening Of Hard, Nacre-Mimetic Mosi2 Coatings By Self-Assembled Hierarchical Structure, Jiang Xu, Xiaoli Zhao, Paul Munroe, Zonghan Xie

Research outputs 2014 to 2021

Like many other intermetallic materials, MoSi2 coatings are typically hard, but prone to catastrophic failure due to their low toughness at ambient temperature. In this paper, a self-assembled hierarchical structure that closely resembles that of nacre (i.e., mother of pearl) was developed in a MoSi2 -based coating through a simple, yet cost-effective, depostion technique. The newly formed coating is tough and can withstand multiple indentations at high loads. Key design features responsible for this remarkable outcome were identified. They include a functionally graded multilayer featuring elastic modulus oscillation, varying sublayer thickness and a columnar structure that are able to attenuate …