Study of the Effect of Retarder and Expander on the Strength and Cracking Performance of Rubber Concrete Based on Back Propagation Neural Network

by 

Chune Sui1,Dan Qiao1,Yalong Wu2,Han Zhu3,Haoyu Lan1,*,Wenjun Yang4 and Qi Guo5

1 Department of Bridge Engineering, Transportation Institute, Inner Mongolia University, Hohhot 010070, China

2 China Railway Fourth Engineering Group Co., Ltd., Hefei 230041, China

3 Department of Civil Engineering, College of Architecture and Engineering, Tianjin University, Tianjin 300000, China

4 Tianjin Shiyi Urban Architectural Design Co., Ltd., Tianjin 300000, China

5 Beijing ZZHX Engineering Research Institute Co., Ltd., Beijing 100000, China

*

Author to whom correspondence should be addressed.

Materials 2023, 16(21), 6976; https://doi.org/10.3390/ma16216976

Received: 10 June 2023 / Revised: 6 July 2023 / Accepted: 18 July 2023 / Published: 31 October 2023

(This article belongs to the Special Issue Construction Materials and Artificial Intelligence)

Abstract:

The advantages of rubber concrete (RC) are good ductility, fatigue resistance, and impact resistance, but few studies have been conducted on the effects of different rubber 

admixtures on the strength of RC and the cracking performance of rubber mortar. In this study, the compressive and flexural tests of rubber concrete and the crack resistance

 test of rubber mortar were carried out by changing the rubber content and adding expansion agent and retarder in this test. The test results show that the strength of RC

 decreases with the increase in rubber admixture. At 15% of rubber admixture, the expansion agent and retarder increase the compressive strength and flexural strength of

 RC the most; the compressive strength increased to 116% (22.6 MPa) and 109% (21.2 MPa), and the flexural strength increased to 111% (4.02 MPa) and 116%. (4.21 MPa). 

At the same rubber admixture, the expander improves the cracking time of the rubber mortar by about 3 times, and the retarder improves the cracking time of the rubber

 mortar by about 1.6 times. The BP neural network (BPNN) was established to simulate and predict the compressive and flexural strengths of RC with different admixtures 

and the cracking time of rubber mortar. The simulation results show that the predicted 7-day compressive strength of RC fits best with the actual value, with a value of 0.994,

 and the predicted 28-day flexural strength was closest to the measured value, with an average relative error of 1.7%. It was shown that the calculation results of the artificial

 intelligence prediction model are more accurate. The simulation results and test results show that the expander and retarder significantly improve the strength of RC as well

 as the cracking performance of rubber mortar.

Keywords: 

rubber concrete; expander; retarder; compressive strength; flexural strength; crack resistance; BP neural network