scholarly journals Influence on the Properties of Concrete Containing Steel Fibers and Alccofine

2020 ◽  
Vol 9 (5) ◽  
pp. 168-170
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
High Performance ◽  
Steel Fibers ◽  
Concrete Technology ◽  
Curing Period ◽  
Innovative Materials ◽  
Better Than

Innovative materials are required in the field of concrete technology for the better construction of the structure. The innovative concrete should have better durability and good aesthetical appearance. The present investigation is aimed at achieving high performance, better and more authentic and uniform quality. In this paper, the effect of Alccofine and conjointly Alccofine and steel fibers, on the mechanical properties of concrete has been evaluated after the curing period of 28 and 56 days. The percentage replacement of Alccofine were adopted as 5%, 10% and 15% and 1% steel fibers were added by mass of concrete. Results showed that compressive and flexural strength increased with an increase in Alccofine percentage. It was also observed that concrete with steel fibers along with 15% Alccofine exhibited highest compressive and flexural strength. Thus, the conjoint presence of Alccofine and steel fibers yields better than concrete without admix.

scholarly journals Effect of Alccofine and Zeolite on the Properties of Concrete Containing Polypropylrne Granules

2020 ◽  
Vol 9 (5) ◽  
pp. 867-871
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Mix Design ◽  
Mineral Admixtures ◽  
Reinforced Concrete Structures ◽  
Concrete Technology ◽  
Curing Period ◽  
Strength Tests ◽  
Innovative Materials ◽  
Better Than

Reinforced concrete structures are affected by various durability problems during their service life. Innovative materials are required in the field of concrete technology for the better construction of the structure. Keeping in view, the present work has been carried out by replacing the cement partially with mineral admixtures namely, Alccofine and Zeolite in different concentrations and by incorporating Polypropylene granules to the concrete. In the present investigation the specimens were divided into three sets. One made with only OPC as binder i.e. conventional mix, second made with OPC and Alccofine/ Zeolite together i.e. binary mix and, third made with OPC, Alccofine and Zeolite together i.e. ternary mix. The varying percentages of Alccofine and Zeolite has been taken as 10% and 15% as a replacement of cement and the polypropylene granules has been fixed at constant 1% for all mix proportions of concrete. The w/c ratio was adopted as 0.45. DOE method of mix design has been adopted. The compressive strength, flexural strength and tensile strength tests have been conducted after the curing period of 28 and 56 days. Results showed that Concrete with 15% replacement of cement by Alccofine and 10% replacement of cement by Zeolite along with 1% Polypropylene granules had shown significant improvement in various mechanical properties at the age of 56 days. It was also observed that concrete with 15% replacement of cement by Alccofine along with 1% Polypropylene granules had shown significant improvement in various mechanical properties at the age of 28 days. Thus, the conjoint presence of Alccofine/Zeolite along with polypropylene granules yields better than concrete without any admix.

Experimental Study on Mechanical Properties of Steel Fiber Reinforced High Performance Concrete

2013 ◽  
Vol 859 ◽  
pp. 56-59 ◽  
Author(s):  
Yong Qiang Ma
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Flexural Strength ◽  
High Performance ◽  
Steel Fiber ◽  
High Performance Concrete ◽  
Steel Fibers ◽  
Fiber Reinforced

A large number of experiments have been carried out in this study to reveal the effect of the steel fiber dosage on the mechanical properties of HPC (high performance concrete). The mechanical property includes compressive strength, elastic modulus and flexural strength. The results indicate that the addition of steel fiber increase the compressive strength, elastic modulus and flexural strength of HPC. When the steel fiber dosage is less than 2%, these mechanical property parameters are increasing gradually with the increase of steel fiber dosage, while these parameters begin to decrease when the steel fiber dosage is more than 2%. With the development of HPC, the application of steel fibers in HPC becomes more and more popular. In the actual construction of steel fiber reinforced HPC, the dosage of steel fiber should be controlled strictly in order to ensure that the steel fibers can perform their best improvement on high performance concrete.

scholarly journals Experimental study on high temperature mechanical properties of aluminate cement mortar mixed with fiber

2021 ◽  
Vol 25 (6 Part B) ◽  
pp. 4441-4448
Author(s):  
Ping Xu ◽  
Dong Han ◽  
Jian-Xin Yu ◽  
Yu-Hao Cui ◽  
Min-Xia Zhang
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Flexural Strength ◽  
Volume Fraction ◽  
Cement Mortar ◽  
Steel Fibers ◽  
Basalt Fibers ◽  
High Temperature Mechanical Properties ◽  
Micro Structures ◽  
Aluminate Cement

The aim of the present paper is to study the mechanical properties of aluminate cement mortar mixed with different chopped fibers under high temperature. The specimens with a size of 40 mm ? 40 mm ? 160 mm is treated at various tempera?tures of 25?C, 200?C, 400?C, 600?C, and 800?C. The compressive and flexural strength of the aluminate cement mortar and its micro-structures are tested. The results show that the chopped steel fibers and basalt fibers are effective in improv?ing the high temperature mechanical properties of aluminate cement mortar. When the volume fraction of chopped steel fibers is 2%, the compressive strength and flexural strength of the test block treated at the temperature of 800?C increase by 18.3% and 128.6%, respectively.

The Effect of the Electrical Discharge Machining Process on the Material Properties of Nonconductive Ceramics

2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Nirdesh Ojha ◽  
Florian Zeller ◽  
Claas Mueller ◽  
Holger Reinecke
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Flexural Strength ◽  
Vickers Hardness ◽  
Electrical Discharge ◽  
High Performance ◽  
Electrical Discharge Machining ◽  
Machining Process ◽  
Hardness Increase ◽  
Edm Process

Electrical discharge machining (EDM) is widely used to manufacture complex shaped dies, molds and critical parts in conductive materials. With the help of an assisting electrode (AE), EDM process can be used to machine nonconductive ceramics. This paper evaluates the mechanical properties of three high-performance nonconductive ceramics (ZrO2, Si3N4, and SiC) that have been machined with the EDM process using AE. Mechanical properties such as Vickers hardness (HV 0.3), surface roughness (Sq), and flexural strength of the machined and the nonmachined samples are compared. The EDM process causes decrease in Vickers hardness, increase in surface roughness, and decrease in flexural strength.

Impact of Steel Fibers on Workability and Properties of UHPC

2016 ◽  
Vol 249 ◽  
pp. 57-61 ◽  
Author(s):  
Milan Rydval ◽  
Tomáš Bittner ◽  
Jiří Kolísko ◽  
Šárka Nenadálová
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
High Performance Concrete ◽  
Volume Fraction ◽  
Fresh Concrete ◽  
Mixture Design ◽  
Steel Fibers ◽  
Hardened Concrete ◽  
Hardened Cement ◽  
The Impact

This paper is focused on properties of fresh and hardened cement-based composite Ultra-High Performance Concrete with regard to different volume fraction of short brass coated steel fibers BASF MASTERFIBER® 482. Workability of fresh concrete and basic mechanical properties (tensile strength in bending, compressive strength) of hardened UHPC were found out. The workability of fresh concrete was measured by small mortar Haegermann cone. Percentage differences at cost were obtained at hardened concrete, too. The aim of the first experimental part of the research was the impact of volume fraction of steel fibers according to workability of fresh concrete and also according to mechanical properties of hardened UHPC with the same volume fraction of each component of the mixture, only the volume fraction of the steel fibers was different at each mixture. The mixture design of UHPC was changed to maintaining the workability of fresh concrete at the second part of the research. The workability at mixture with dosage of steel fibers of 300 kg/m3 measured by Haegermann cone was around 300 mm. In the framework of grant project GAČR 15-05791S the basic mechanical properties of hardened fine-grained cementitious composite material UHPC at small beams size of 160/40/40 mm and beams size 300/70/70 mm were determined. The aim of the research project was not only the determination of basic mechanical properties for each mixture design but also workability assessment and costs linked with higher amount of the volume fracture of steel fibers.

Evaluation of Fundamental UHPC Properties According to the Shape of Steel Fiber

2010 ◽  
Vol 452-453 ◽  
pp. 717-720 ◽  
Author(s):  
Gum Sung Ryu ◽  
Su Tae Kang ◽  
Jung Jun Park ◽  
Kyung Taek Koh ◽  
Sung Wook Kim
Keyword(s):  
Aspect Ratio ◽  
Flexural Strength ◽  
High Performance ◽  
High Performance Concrete ◽  
Steel Fibers ◽  
Flexural Behavior ◽  
Ultra High Performance Concrete ◽  
Aspect Ratios ◽  
Strength Tests ◽  
Shaped Fibers

This paper intends to examine the effects if the length and shape of steel fibers on the mechanical characteristics of ultra-high performance concrete (UHPC). Accordingly, the length (l) of the steel fibers with diameter (d) of 0.2 mm is varied as 13 mm, 16.3 mm and 19.5 mm and their corresponding aspect ratios (l/d) are 65, 82 and 98. Straight and wave-shaped fibers are adopted to manufacture UHPC. Thereafter, the effects of the aspect ratio and characteristics of the wave-shape of the steel fibers on the strength characteristics of UHPC are examined through compressive and flexural strength tests. The results showed small differences in the workability and compressive behavior but revealed that changing the length of the fibers and increasing the aspect ratio are improving the flexural behavior of UHPC. Specifically, the flexural strength was enhanced by 25% and the flexural toughness by 30%. Compared to rectilinear fibers, the adoption of wave-shaped fibers is seen to degrade the flexural behavior regardless of the aspect ratio. Consequently, using straight steel fibers and adopting larger aspect ratio seems advisable to improve the toughness of UHPC.

Performance of ilmenite concrete at sustained elevated temperatures

1988 ◽  
Vol 15 (5) ◽  
pp. 776-783
Author(s):  
H. S. Wilson
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
High Temperature ◽  
Flexural Strength ◽  
Key Words ◽  
Elevated Temperatures ◽  
Cement Ratio ◽  
Nondestructive Tests ◽  
High Temperature Mechanical Properties ◽  
Curing Period

Two similar mixes were made with cement contents of about 350 kg/m3 and a water–cement ratio of 0.50. The concrete specimens, moist cured for 7 days, were cured in air for 28 and 120 days, respectively, prior to heating. The exposure temperatures were 75, 150, 300, and 450 °C. The periods of exposure at each temperature were 2, 30, and 120 days.The compressive strengths, before heating, of the specimens cured for 35 and 120 days were 41.0 and 46.2 MPa, respectively, and the flexural strengths were 4.9 and 5.8 MPa. Compared with those strengths, the strengths of the specimens heated for 30 days or more increased at 75 °C but decreased at higher temperatures. The losses increased with increase in temperature, reaching about 30% at 450 °C.The flexural strength of the concrete cured in air for 28 days was more adversely affected than was the compressive strength. The flexural and compressive strengths of the concrete cured in air for 120 days were affected to about the same degree. The longer curing period had little effect on the relative losses in compressive strength, but the longer curing period reduced the loss in flexural strength. In most applications, the loss in strength could be compensated by proportioning the mix to overdesign for strength. Key words: high-density concrete, ilmenite, aggregates, high temperature, mechanical properties, nondestructive tests.

Influence of Variable Temperature Curing on Mechanical Properties of Fly Ash Concrete

2011 ◽  
Vol 250-253 ◽  
pp. 178-181
Author(s):  
Ya Ding Zhao ◽  
Xue Ying Li ◽  
Ling Chao Kong ◽  
Wei Du
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Fly Ash ◽  
Flexural Strength ◽  
Variable Temperature ◽  
Improve Performance ◽  
Curing Conditions ◽  
Fly Ash Concrete ◽  
Better Than

Under variable temperature curing conditions(30 oC ~70 oC), concrete with fly ash whose compressive strength, flexural strength, and dynamic elastic modulus are better than ones without fly ash.Compared with constant temperature 20oC, 50 oC and 70 oC, variable temperature curing(VTC) is benefit for the improvement of mechanical properties of 30% fly ash concrete, but which is no advantage to improve performance of 50% fly ash concrete.

scholarly journals On enhancing the mechanical behavior of ultra-high performance concrete through multi-scale fiber reinforcement

2021 ◽  
Author(s):  
Ketan Ragalwar ◽  
William Heard ◽  
Brett Williams ◽  
Dhanendra Kumar ◽  
Ravi Ranade
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
High Performance Concrete ◽  
Underlying Mechanism ◽  
Steel Fibers ◽  
Flexural Behavior ◽  
Steel Wool ◽  
Multi Scale ◽  
Pull Out ◽  
Fiber Matrix

Steel fibers are typically used in ultra-high performance concretes (UHPC) to impart flexural ductility and increase fracture toughness. However, the mechanical properties of the steel fibers are underutilized in UHPC, as evidenced by the fact that most of the steel fibers pull out of a UHPC matrix largely undamaged during tensile or flexural tests. This research aims to improve the bond between steel fibers and a UHPC matrix by using steel wool. The underlying mechanism for fiber-matrix bond improvement is the reinforcement of the matrix tunnel, surrounding the steel fibers, by steel wool. Single fiber pullout tests were performed to quantify the effect of steel wool content in UHPC on the fiber-matrix bond. Microscopic observations of pulled-out fibers were used to investigate the fiber-matrix interface. Compared to the control UHPC mixture with no steel wool, significant improvement in the flexural behavior was observed in the UHPC mixtures with steel wool. Thus, the addition of steel wool in steel fiber-reinforced UHPC provides multi-scale reinforcement that leads to significant improvement in fiber-matrix bond and mechanical properties of UHPC.

scholarly journals Performance of Cracked Ultra-High-Performance Fiber-Reinforced Concrete Exposed to Dry-Wet Cycles of Chlorides

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Longlong Niu ◽  
Shiping Zhang
Keyword(s):  
Reinforced Concrete ◽  
Flexural Strength ◽  
High Performance ◽  
Chloride Ion ◽  
Fiber Reinforced Concrete ◽  
Steel Fibers ◽  
Self Healing ◽  
Fiber Reinforced ◽  
High Performance Fiber ◽  
Corrosion Of Steel

This paper presents an experimental study on the performance of cracked ultra-high-performance fiber-reinforced concrete (UHPC) exposed to dry-wet cycles of 3.5% NaCl solution under the temperature of 60°C. The results show that the wider the crack, the higher the corrosion degree of steel fibers embedded in UHPC, and the deeper the chloride ion diffusion on both sides of the crack. With the increase of dry-wet cycles, the flexural strength of precracked UHPC first decreases and then increases, and the lowest flexural strength was observed in 60 dry-wet cycles. Although self-healing is hard to cease the corrosion of steel fibers, it can relieve the corrosion of steel fibers and improve the flexural strength exposed to 100 dry-wet cycles.

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