Factor affecting the bond quality of functionally graded concretes produced with steel fiber and recycled aggregates

2021 ◽  
Vol 54 (4) ◽  
Author(s):  
Ricardo Chan ◽  
Charles K. S. Moy ◽  
Isaac Galobardes
2019 ◽  
Vol 26 (3) ◽  
pp. 37-42
Author(s):  
Ashtar S. Al-Luhybi

In the building process, the recycling of aggregates arising from building and demolition debris is one of the best alternatives to maintain the environment and the areas needed to bury these debris. It also helps to preserve natural concrete sources from depletion efficiently. The use of recycled aggregates in new concrete manufacturing, however, leads to a decrease in concrete\\\’s strength characteristics. This reduction rises with the rise in the percentage of recycled aggregates used in concrete, which has caused many researchers to undertake many researches on how to enhance the characteristics of recycled aggregate-containing concrete. This paper presents several studies that examined the effect of adding steel fiber to improve the properties of concrete containing a coarse recycled aggregate.


PCI Journal ◽  
2021 ◽  
Vol 66 (2) ◽  
pp. 71-87
Author(s):  
Sandip Chhetri ◽  
Rachel A. Chicchi ◽  
Andrew E. N. Osborn

Very little experimental data have been published relating to the pullout capacity of prestressing strand lifting loops. To address this gap in knowledge, 13 pullout tests were conducted on strand lifting loops with 0.6 in. (15.24 mm) diameter, 270 ksi (1860 MPa) strand. Straight and bent orientations were tested for single loops at different embedment depths. Loops were embedded in 12 in. (304.8 mm) wide and 44 in. (1117.6 mm) deep concrete blocks and subjected to monotonic, static loading until failure. Marginal bond quality of the strand (18.2 kip [81 kN]), Mohs hardness (3.6), and concrete strength (3000 psi [20.7 MPa]) resulted in an average bond stress value of 400 psi (2758 kPa) at failure. Most tests exhibited pullout failure modes and adequate ductility. Three loops tested at 32 in. (812.8 mm) embedment with 6 in. (152.4 mm), 90-degree bends experienced brittle side-face blowout failures. These failures were due to inclination of the lifting, which led to a reduced edge distance. A safe uniform bond stress of 199 psi (1372 kPa) is recommended for 0.6 in. diameter strand.


2017 ◽  
Vol 18 (1) ◽  
pp. 32-38 ◽  
Author(s):  
Eka Mulya Alamsyah ◽  
Ihak Sumardi ◽  
Sutrisno . ◽  
Atmawi Darwis ◽  
Yoyo Suhaya

Author(s):  
Satoshi Fujiwara ◽  
Toshiki Takamizawa ◽  
Wayne W. Barkmeier ◽  
Akimasa Tsujimoto ◽  
Arisa Imai ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document