Experimental and Numerical Characterization of Self-Compacting Concrete «Using Construction Waste»

2015 ◽  
Vol 749 ◽  
pp. 353-357 ◽  
Author(s):  
Hassiba Hermime ◽  
Youcef Bouafia ◽  
Sarah Benakli
Keyword(s):  
Shear Force ◽  
Mechanical Tests ◽  
Test Results ◽  
Numerical Characterization ◽  
Fresh State ◽  
Hardened State ◽  
Mechanical Performances ◽  
Direct Tensile ◽  
Direct Tensile Test

This work carries an experimental study on the composition and the characterization of the self-compacting concretes made starting from waste of construction with comparisons which were made by contribution with the vibrated concrete. Studies on the workability and the compactness of material were made and this in a fresh state and a hardened state. Five different mechanical tests were performed: compression, direct tensile, splitting tensile, 3 points binding and failure to the shear force. Confrontations of the test results compared to formulas for calculating the shear force were realized. All the test results showed an increase in terms of resistance for SCC contribution to the VC, except the direct tensile test which gave values slightly lower. The SCC improves the failure load notably and gives better mechanical performances.

scholarly journals Experimental Study on Ready-Mix Concrete: Case Study

2018 ◽  
Vol 149 ◽  
pp. 01071
Author(s):  
Dorra Ellouze ◽  
Aida Ghammouri ◽  
Rahma Ben Amar
Keyword(s):  
Building Materials ◽  
Mechanical Tests ◽  
Professional Life ◽  
Price Ratio ◽  
Minimal Cost ◽  
Concrete Case ◽  
Fresh State ◽  
Hardened State ◽  
Ready Mix Concrete

Ready-mix concrete (RMC) in Tunisia is becoming more and more in demand in the civil engineering sector thanks to its qualities of handling in the fresh state and resistance in the hardened state, this composite material must respect the quality-price ratio. A RMC with a minimal cost is the object of our work. This research is part of the opening of higher education on professional life, where we optimized the formulation of a RMC. This work has 3 axes. In the first place the resources in building materials were characterized, namely various samples of sand, gravel, cement and water. Subsequently, the adjuvant-cement ratio (A/C) was optimized. Finally, the workability of the concrete as well as its mechanical aptitude at various ages 7, 14 and 28 days were characterized. These examinations have resulted in an appropriate formulation for any type of resource that varies according to the provenance of the quarries (gravel and sand), the effect of the plasticizer-water reducer is found for a very interesting A/C ratio, the mechanical tests for different ages are also conclusive.

Experimental investigation of recycled aggregate effect on the concrete properties

2018 ◽  
Vol 9 (4) ◽  
pp. 560-571
Author(s):  
Hamed Hemmati Pourghashti ◽  
Malek Mohammad Ranjbar ◽  
Rahmat Madandoust
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Tensile Test ◽  
Recycled Concrete ◽  
Test Results ◽  
Content Type ◽  
Treatment Conditions ◽  
Natural Aggregates ◽  
Direct Tensile ◽  
Direct Tensile Test

Purpose The purpose of this paper is to conduct a laboratory investigation on measuring the tensile strength of recycled concrete using a double punch test. Furthermore, one of the main goals of this study is to compare the tensile and compressive strengths of recycled concrete samples. Design/methodology/approach Recycled concrete samples were made with variables such as aggregate type (natural stone and aggregate recycled concrete), different water-to-cement ratios and different treatment conditions in the first stage. In the next stage, the double punch test was performed on them, and finally the results obtained from experiments were analyzed and investigated. Findings According to the above tests, it was concluded that: first, according to the laboratory results, the strength of concrete containing recycled aggregates becomes closer to the strength of concrete containing natural aggregates whenever the water-to-cement ratio is higher. Second, upon investigating the treatment conditions, it was observed that the treatment had a greater effect on the strength of the recycled concrete. However, this effect was less tangible in tensile strength. Third, upon investigating the results of tensile strength, it can be said that the Barcelona test results were closer to the direct tensile test results compared to the Brazilian test results. This indicates the higher viability of Barcelona’s test results. Fourth, the results obtained from the Barcelona tensile test for recycled concrete were closer to the results of the direct tensile test compared to the concrete containing natural aggregates, which suggests that the Barcelona test is more suitable as a tensile test for recycled concrete. Fifth, the effects of various factors on tensile strength were somewhat less compared to the compressive strength, although very close. Sixth, the relationships provided by the regulation for concrete tensile strength on compressive strength were highly inconsistent with the results obtained from the direct tensile test, for which the consistency was higher for concrete containing natural aggregates compared to recycled concrete. Seventh, the dispersion of results obtained from tensile tests was higher for recycled concrete compared to concrete containing natural aggregates, but lesser of this dispersion was observed in the compressive strength. Originality/value According to the laboratory results, the strength of concrete containing recycled aggregates becomes closer to the strength of concrete containing natural aggregates whenever the water-to-cement ratio is higher. Upon investigating the treatment conditions, it was observed that the treatment had a greater effect on the strength of the recycled concrete. However, this effect was less tangible in tensile strength. On the basis on the results of the tensile strength, it can be said that the Barcelona test results were closer to the results of the direct tensile test compared to those of the Brazilian test. This indicates the higher viability of Barcelona’s test results. The results obtained from the Barcelona tensile test for recycled concrete were closer to the results of direct tensile test compared to the concrete containing natural aggregates, which suggests that the Barcelona test is more suitable as a tensile test for recycled concrete. The effects of various factors on tensile strength were somewhat less compared to the compressive strength, although very close. The relationships provided by the regulation for concrete tensile strength on compressive strength were highly inconsistent with the results obtained from the direct tensile test, for which the consistency was higher for concrete containing natural aggregate compared to recycled concrete. The dispersion of results obtained from tensile tests was higher for recycled concrete compared to concrete containing natural aggregate, but lesser of this dispersion was observed in the compressive strength.

Microstructure and Mechanical Properties of n-Irradiated Fe-Cr Model Alloys

2006 ◽  
Vol 981 ◽  
Author(s):  
Milena Matijasevic ◽  
Abderrahim Al Mazouzi
Keyword(s):  
Mechanical Stability ◽  
Tensile Tests ◽  
High Energy ◽  
Mechanical Tests ◽  
Test Results ◽  
Martensitic Steels ◽  
Irradiation Hardening ◽  
Cr Concentration ◽  
Accelerator Driven Systems

AbstractHigh chromium ( 9-12 wt %) ferritic/martensitic steels are candidate structural materials for future fusion reactors and other advanced systems such as accelerator driven systems ADS). Their use for these applications requires a careful assessment of their mechanical stability under high energy neutron irradiation and in aggressive environments. In particular, the Cr concentration has been shown to be a key parameter to be optimized in order to guarantee the best corrosion and swelling resistance, together with the least embrittlement.In this work, the characterization of the neutron irradiated Fe-Cr model alloys with different Cr % with respect to microstructure and mechanical tests will be presented. The behavior of Fe-Cr alloys have been studied using tensile tests at different temperature range ( from -160°C to 300°C). Irradiation-induced microstructure changes have been studied by TEM for two different irradiation doses at 300°. The density and the size distribution of the defects induced have been determined. The tensile test results indicate that Cr content affects the hardening behavior of Fe-Cr binary alloys. Hardening mechanisms are discussed in terms of Orowan type of approach by correlating TEM data to the measured irradiation hardening.

Characterization of a self-compacting sand concrete using the quarry waste

2009 ◽  
Vol 36 (11) ◽  
pp. 1773-1782 ◽  
Author(s):  
A. Abidelah ◽  
A. Bouchaïr ◽  
D. Kerdal ◽  
K. Ayed
Keyword(s):  
Mechanical Behavior ◽  
Rheological Behavior ◽  
Environmental Problem ◽  
Mechanical Performance ◽  
Maximum Size ◽  
Water Volume ◽  
Volume Weight ◽  
Fresh State ◽  
Hardened State

Self-compacting sand concrete (SCSC) can be made by using the quarry waste, thus helping to reduce the actual deficit in aggregates in Algeria and contribute to the solution of an acute environmental problem. The SCSC presented in this paper is made with aggregates whose maximum size is less than 5 mm. Several mixes were prepared by varying parameters, such as water volume, weight and nature of cement, weight of sand, nature of admixtures, and shape of aggregates. Each one of the SCSC mixes has been analyzed by considering its rheological behavior in the fresh state and its mechanical behavior in the hardened state. In the fresh state, the elaborated SCSC satisfies the recommendations of the Association Française de Génie Civil (AFGC) and in the hardened state, its mechanical performance is good.

Mechanical Behavior of Overlap-Welded of Dissimilar Steels (Structural-Stainless) under Monotonic Load

2012 ◽  
Vol 557-559 ◽  
pp. 1268-1274 ◽  
Author(s):  
Andrés L. García Fuentes ◽  
Pierre Bazán ◽  
Leiry Centeno ◽  
Magaly Ramos ◽  
Alberto Velázquez Del Rosario
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Welding Process ◽  
Mechanical Tests ◽  
Bending Test ◽  
Hardness Profile ◽  
Test Results ◽  
Electrical Arc ◽  
Arc Welding Process

The research shows the characterization of mechanical properties in dissimilar steel welded unions: a structural steel ASTM A537 (I) overlap welded with an austenitic stainless steel ASTM A240 (304L) through semiautomatic electrical arc welding process protected by inert gas (GMAW); Argon is used as a protecting gas and austenitic stainless steel ASTM A240 (308L) as a supplier material. Samples were tested in not welded conditions so as to characterize the materials involved in the research, and they were also tested in welded conditions, not being submitted to pre and post welding Thermal Treatment (TT). Welded-based material samples were characterized through Optical Microscopy (OM) and Scanning Electron Microscopy (SEM), an inspection of Not Destructive Test (NDT) with penetrating liquids and ultrasound was also conducted. The following mechanical tests were completed, not only on the Base Metals (BM), on the Welding Join (WJ) as well: Vickers micro hardness profile, tension, and face bending test. Results showed a proper mechanical steel behavior, welded by GMAW procedure, under monotonic, in spite of the relatively high values of microhardness in the Heat Affected Zone (HAZ), specifically near the fusion line between weld and stainless steel.

Verification of Mechanical Properties of A V-4Cr-4Ti Alloy Using Finite Element Method

2005 ◽  
Vol 297-300 ◽  
pp. 1013-1018
Author(s):  
Choon Yeol Lee ◽  
E.G. Donahue ◽  
G.R. Odette
Keyword(s):  
Finite Element ◽  
Experimental Studies ◽  
Mechanical Tests ◽  
Constitutive Law ◽  
Fracture Mechanisms ◽  
Test Results ◽  
Element Analysis ◽  
Vanadium Alloys ◽  
Fracture Specimens

Vanadium alloys in the composition range around V-4Cr-4Ti have been proposed as candidate materials for fusion reactor applications and structures. These applications will require detailed characterization of constitutive and fracture properties. This study is aimed at understanding the basic constitutive and fracture mechanisms in vanadium alloys. Understanding of the basic constitutive and fracture mechanisms is achieved through a series of mechanical tests. These test results are combined with quantitative models of the underlying macro- and micromechanics. In addition to these experimental studies, finite element analysis (FEA) techniques are used to determine stress and strain fields to verify the constitutive law used in the fracture specimens.

Mechanical Characterization of SRG Composites According to AC434

2019 ◽  
Vol 817 ◽  
pp. 458-465 ◽  
Author(s):  
Davide Campanini ◽  
Houman A. Hadad ◽  
Christian Carloni ◽  
Claudio Mazzotti ◽  
Antonio Nanni
Keyword(s):  
High Strength ◽  
The United States ◽  
Test Method ◽  
Strain Behavior ◽  
Existing Structures ◽  
Steel Cords ◽  
Humidity Chamber ◽  
Direct Tensile ◽  
Direct Tensile Test

In the last decades, technologies and materials such as fiber reinforced polymer (FRP) have been used to strengthen different types of existing structures. More recently, composites have been developed consisting of reinforcement fabrics embedded in an inorganic mortar. These composites are known as fabric reinforced cementitious matrix (FRCM), when the fabric is made of aramid, glass, basalt, polyparaphenylene benzo-bisoxazole (PBO) or carbon fibers, and steel reinforced grout (SRG), when the fabric is made of twisted high-strength steel cords. In the United States, the characterization of FRCM/SRG systems is conducted in accordance to Acceptance Criteria AC434. According to AC434, the tensile properties of FRCM/SRG are obtained through a direct tensile test on coupons using clevis grips.The objective of this research is to discuss the applicability of the AC434 test method to determine the mechanical properties of SRG as a function of the length of the anchoring plates. SRG panels were cast and stored in a humidity chamber. After a 28-day curing period, they were cut to size and metal plates of different lengths adhered to their extremities. Results show that not all the assumptions currently made in AC434 are applicable to this type of composite. The experimental response was characterized by a trilinear stress-strain behavior. Furthermore, the cracked modulus calculated based on stress values between 60 and 90% of the ultimate stress does not accurately represent reality. Re-evaluation of this provision is of importance since the cracked modulus is used in design.

scholarly journals The The Effects of Recycled Tire Rubbers and Steel Fibers on the Performance of Self-compacting Alkali Activated Concrete

2021 ◽  
Author(s):  
Necip Altay Eren ◽  
Radhwan Alzeebaree ◽  
Abdulkadir Çevik ◽  
Anıl Niş ◽  
Alaa Mohammedameen ◽  
...  
Keyword(s):  
Granulated Blast Furnace Slag ◽  
Structural Applications ◽  
Fresh State ◽  
Hardened State ◽  
Strength And Deformation ◽  
Natural Aggregates ◽  
Mechanical Performances ◽  
Mechanical Strengths ◽  
Alkali Activated Concrete ◽  
Alkali Activated

In this study, the effects of recycled tire rubbers (RTR) and steel fiber (SF) on the fresh and hardened state properties of the self-compacted alkali activated concrete (SCAAC) were investigated. The ground granulated blast furnace slag, 1 % hooked-end SF, and two types of RTR were utilized. The crumb rubbers (CR) and tire rubber chips (TCR) were used as a substation to natural aggregates at substation levels of 10 % and 15 %. The fresh state performances were evaluated by T50 value, slump flow, V-funnel, and L-Box tests, while mechanical performances were assessed through compressive, flexural, and splitting tensile strength tests. Also, detailed crack and microstructural analyses were conducted. The RTR adversely affected the fresh state properties, which reduced more with SF inclusions. Among the RTR, the TR specimens exhibited lower fresh state performance than the CR specimens. Similar mechanical strengths were obtained on the TR and CR specimens under the same replacement ratios. However, TR specimens exhibited higher deformation capacities than the CR specimens, when SF was utilized. The SCAAC specimens with 1 % SF and 15 % RTR showed more and wider flexural cracks, higher mechanical strength, and deformation capacity, which can be utilized in structural applications, particularly in high seismic zones.

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