An experimental and numerical study on how steel and polypropylene fibers affect the impact resistance in fiber-reinforced concrete

2012 ◽  
Vol 46 ◽  
pp. 62-73 ◽  
Author(s):  
A. Alavi Nia ◽  
M. Hedayatian ◽  
M. Nili ◽  
V. Afrough Sabet
2014 ◽  
Vol 578-579 ◽  
pp. 501-504
Author(s):  
Guo Chao Wang ◽  
Bo Xin Wang

The incorporation of a small amount of steel fibers or fine polypropylene fibers in concrete can increase its impact resistance. But steel fiber has the problems of corrosion, high cost and high mess. The effect of fine polypropylene fibers in inhibiting the impact crack is not effective. The research was taken to measure the properties of fresh concrete mixture of Synthetic Macro-fiber reinforced concrete. And investigated the influence of fiber length and volume fraction on the impact resistance of Synthetic Macro-fiber reinforced concrete. The results showed that these fibers could obviously improve the impact resistance of concrete. There was a best Synthetic Macro-fiber volume fraction. The length of the Synthetic Macro-fiber had a certain influence on the impact resistance of concrete.


2020 ◽  
Vol 14 (2) ◽  
pp. 6734-6742
Author(s):  
A. Syamsir ◽  
S. M. Mubin ◽  
N. M. Nor ◽  
V. Anggraini ◽  
S. Nagappan ◽  
...  

This study investigated the combine effect of 0.2 % drink cans and steel fibers with volume fractions of 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the mechanical properties and impact resistance of concrete. Hooked-end steel fiber with 30 mm and 0.75 mm length and diameter, respectively was selected for this study.  The drinks cans fiber were twisted manually in order to increase friction between fiber and concrete. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the strength performance of concrete, especially the compressive strength, flexural strength and indirect tensile strength. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the compressive strength, flexural strength and indirect tensile strength by 2.3, 7, and 2 times as compare to batch 1, respectively. Moreover, the impact resistance of fiber reinforced concrete has increase by 7 times as compared to non-fiber concretes. Moreover, the impact resistance of fiber reinforced concrete consistently gave better results as compared to non-fiber concretes. The fiber reinforced concrete turned more ductile as the dosage of fibers was increased and ductility started to decrease slightly after optimum fiber dosage was reached. It was found that concrete with combination of 2% steel and 0.2% drink cans fibers showed the highest compressive, split tensile, flexural as well as impact strength.    


1985 ◽  
Vol 64 ◽  
Author(s):  
Surendra P. Shah

ABSTRACTDespite its extensive use, low tensile strength has been recognized as one of the major drawbacks of concrete. Although one has learned to avoid exposing concrete structures to adverse static tensile load, these cannot be shielded from short duration dynamic tensile stresses. Such loads originate from sources such as impact from missiles and projectiles, wind gusts, earthquakes and machine vibrations. The need to accurately predict the structural response and reserve capacity under such loading has led to an interest in the mechanical properties of the component materials at high rates of straining.One method to improve the resistance of concrete when subjected to impact and/or impulsive loading is by the incorporation of randomly distributed short fibers. Concrete (or Mortar) so reinforced is termed fiber reinforced concrete (FRC). Moderate increase in tensile strength and significant increases in energy absorption (toughness or impact-resistance) have been reported by several investigators in static tests on concrete reinforced with randomly distributed short steel fibers. A theoretical model to predict fracture toughness of FRC is proposed. This model is based on the concept of nonlinear elastic fracture mechanics.As yet no standard test methods are available to quantify the impact resistance of such composites, although several investigators have employed a variety of tests including drop weight, swinging pendulums and the detonation of explosives. These tests though useful in ascertaining the relative merits of different composites do not yield basic material characteristics which can be used for design.The author has recently developed an instrumented Charpy type of impact test to obtain basic information such as load-deflection relationship, fracture toughness, crack velocity and load-strain history during an impact event. From this information, a damage based constitutive model was proposed. Relative improvements in performance due to the addition of fibers as observed in the instrumented tests are also compared with other conventional methods.


Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5603
Author(s):  
Sun-Jae Yoo ◽  
Tian-Feng Yuan ◽  
Se-Hee Hong ◽  
Young-Soo Yoon

In this study, the performance of reinforced concrete slabs strengthened using four methods was investigated under impact loads transferred from the top side to bottom side. The top and bottom sides of test slabs were strengthened by no-slump high-strength, high-ductility concrete (NSHSDC), fiber-reinforced-polymer (FRP) sheet, and sprayed FRP, respectively. The test results indicated that the test specimens strengthened with FRP series showed a 4% increase in reaction force and a decrease in deflection by more than 20% compared to the non-strengthened specimens. However, the specimen enhanced by the NSHSDC jacket at both the top and bottom sides exhibited the highest reaction force and energy dissipation as well as the above measurements because it contains two types of fibers in the NSHSDC. In addition, the weight loss rate was improved by approximately 0.12% for the NSHSDC specimen, which was the lowest among the specimens when measuring the weight before and after the impact load. Therefore, a linear relationship between the top and bottom strengthening of the NSHSDC and the impact resistance was confirmed, concluding that the NSHSDC is effective for impact resistance when the top and bottom sides are strengthened. The results of the analysis of the existing research show that the NSHSDC is considered to have high impact resistance, even though it has lower resistance than the steel fiber reinforced concrete and ultra-high-performance-concrete, it can be expected to further studies on strengthening of NSHSDC.


2011 ◽  
Vol 82 ◽  
pp. 26-35
Author(s):  
Nemy Banthia

Since 9/11, there has been an increased interest in developing a better understanding of the properties of concrete structures under impact and blast loading. Although concrete, as a material, demonstrates extreme brittleness under dynamically applied loads, fortunately, fiber reinforcement significantly enhances such resistance. Yet, the dynamic properties of both concrete and fiber reinforced concrete (FRC) remain poorly understood. This paper provides a historical perspective of our efforts aimed at understanding the impact resistance of fiber reinforced concrete, highlights some of the issues and challenges encountered and identifies the emerging areas where further research is necessary.


2013 ◽  
Vol 357-360 ◽  
pp. 1049-1052 ◽  
Author(s):  
Xian Dong Wang ◽  
Chang Zhang ◽  
Zhen Huang ◽  
Guo Wei Chen

This paper studied experimentally the impact mechanical properties of bamboo fiber and hybrid steel fiber reinforced concrete. Steel fiber is already used in construction widely, but it is expensive in cost. As a kind of green building material, bamboo fiber can be used in the infrastructures together with concrete to improve the concretes mechanical properties. In order to investigate the impact mechanical properties of concrete reinforced with bamboo fiber and steel fiber, a series of concrete specimens reinforced with bamboo fiber, steel fiber or both steel fiber and bamboo fiber are investigated with self-designed impact device. The impact resistance abilities are tested and compared.


2018 ◽  
Vol 7 (2) ◽  
pp. 742
Author(s):  
Sabapathy Y K ◽  
Ramya Sajeevan ◽  
Rekha J ◽  
Vishal V ◽  
Sabarish S ◽  
...  

Concrete is typically a brittle material which is prone to damage when subjected to heavy impact loads. To overcome this weakness, concrete is reinforced with fibers as fibers are effective in withstanding heavy impact loads. The main objective of this experimental investigation is to study the influence of sisal fibers in concrete under impact load. The impact specimens are prepared using three grades of concrete- M20, M30 and M40 with five varying percentage of fibers- 0%, 0.5%, 1%, 1.5% and 2%. The mix designs of the respective grades of concrete are made as per the Indian standards. The specimens after curing for 28 days were subjected to impact loads using the standard drop weight impact machine confining to ASTM standards. Also cube and cylinder specimens are prepared and tested to ascertain the compressive and tensile strength of the sisal fiber reinforced concrete. The results indicated that the sisal fibers are effective in increasing the impact strength of concrete.


2014 ◽  
Vol 584-586 ◽  
pp. 1630-1634
Author(s):  
Xin Hua Cai ◽  
Zhen He ◽  
Wen Liu

PVA fiber reinforced cement-based composite is a new high-performance cement-based composite material, which usually manufactured with PVA short fibers (does not exceed 2.5% vol.) and cement-based matrix. It has a significant strain-hardening characteristic and excellent crack controlling ability. Its ultimate tensile strain is up to 3% and crack width is not exceed 100μm. PVA fiber reinforced cement-based composite can be utilized to fabricated high energy absorption opponents, such as protective shield, seismic joint, impact-resistant site, etc. In this paper, the basic mechanical properties of PVA fiber reinforced cement-based composite has been tested and verified first. Then the impact resistance of PVA reinforced cement-based composite has been investigated via drop weight impact test, and compared with ones of plain concrete and steel fiber reinforced concrete with the same strength grade. Through analyzing the test results, it is concluded that PVA reinforced cement-based composite’s impact energy absorption is 48 times than plain concrete, and 9 times than steel fiber reinforced concrete respectively. The impact numbers of PVA reinforced cement-based composite is slightly lower than steel fiber reinforced concrete, but its impact absorption energy after initial cracking is 15 times than steel fiber reinforced concrete. In conclusion, PVA reinforced cement-based composite is an excellent impact material.


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