Techno Press
You logged in as. Techno Press

Advances in Concrete Construction
  Volume 14, Number 5, Novmber 2022 , pages 317-330
DOI: https://doi.org/10.12989/acc.2022.14.5.317
 


Study of cracks in compressed concrete specimens with a notch and two neighboring holes
Vahab Sarfarazi, Kaveh Asgari, Shirin Jahanmiri, Mohammad Fatehi Marji, and Alireza Mohammadi Khachakini

 
Abstract
    This paper investigated computationally and experimentally the interaction here between a notch as well as a micropore under uniaxial compression. Brazilian tensile strength, uniaxial tensile strength, as well as biaxial tensile strength are used to calibrate PFC2d at first. Then, uniaxial compression test was conducted which they included internal notch and micro pore. Experimental and numerical building of 9 models including notch and micro pore were conducted. Model dimensions of models are 10 cm × 10 cm × 5 cm. Joint length was 2 cm. Joints angles were 30°, 45° and 60°. The position of micro pore for all joint angles was 2cm upper than top of the joint, 2 cm upper than middle of joint and 2 cm upper than the joint lower tip, discreetly. The numerical model's dimensions were 5.4 cm × 10.8 cm. The fractures were 2 cm in length and had angularities of 30, 45, and 60 degrees. The pore had a diameter of 1 cm and was located at the top of the notch, 2 cm above the top, 2 cm above the middle, and 2 cm above the bottom tip of the joint. The uniaxial compression strength of the model material was 10 MPa. The local damping ratio was 0.7. At 0.016 mm per second, it loaded. The results show that failure pattern affects uniaxial compressive strength whereas notch orientation and pore condition impact failure pattern. From the notch tips, a two-wing fracture spreads almost parallel to the usual load until it unites with the sample edge. Additionally, two wing fractures start at the hole. Both of these cracks join the sample edge and one of them joins the notch. The number of wing cracks increased as the joint angle rose. There aren't many AE effects in the early phases of loading, but they quickly build up until the applied stress reaches its maximum. Each stress decrease was also followed by several AE effects. By raising the joint angularities from 30° to 60°, uniaxial strength was reduced. The failure strengths in both the numerical simulation and the actual test are quite similar.
 
Key Words
    compression test; notch; PFC2D; pore
 
Address
(1) Vahab Sarfarazi:
Department of Mining Engineering, Hamedan University of Technology, Hamedan, Iran;
(2) Kaveh Asgari:
Department of Mining Engineering, Shahid Bahonar University of Kerman, Kerman, Iran;
(3) Shirin Jahanmiri, Alireza Mohammadi Khachakini:
Hamedan University of Technology, Hamedan, Iran;
(4) Mohammad Fatehi Marji:
Department of Mining Engineering, Yazd University, Yazd, Iran.
 
References
    -acc1405003-
 

Techno-Press: Publishers of international journals and conference proceedings.       Copyright © 2025 Techno Press
P.O. Box 33, Yuseong, Daejeon 305-600 Korea, Tel: +82-42-828-7996, Fax : +82-42-828-7997, Email: admin@techno-press.com