PSI - Issue 70

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ScienceDirect

Procedia Structural Integrity 70 (2025) 409–416

Structural Integrity and Interactions of Materials in Civil Engineering Structures (SIIMCES-2025) Microstructural study on Resistance to Chemical Attacks and Structural Integrity of Concrete Durability with Rubber Fine Aggregate and Steel Slag R. Mohanraj a, *, Rishab Bansal a , G. Karthikeyan b , A. Sree Rameswari c a Civil Engineering, Faculty of Engineering & Technology, SRM University, Delhi-NCR, Sonipat 131029, Haryana, India b Civil Engineering, Ramco Institute of Technology, Rajapalayam 626117, Tamilnadu, India c Civil Engineering, PSNA College of Engineering and Technology, Dindigul 624622, Tamilnadu, India Abstract This study investigated the durability of an improved concrete mixture incorporating rubber fine aggregate (RFA) and steel slag (SS) as partial replacements for natural aggregates. The primary aim was to evaluate the resistance of this eco-friendly concrete mixture to acid attack and salt encrustation, which are critical factors influencing the longevity of concrete structures. Two concrete mixtures were prepared: a control and optimized mixture containing 9% RFA and 9% SS. The durability tests included immersing the concrete samples in 5% solutions of hydrochloric acid (HCl) and sulfuric acid (H 2 SO 4 ) for 28 days to assess weight loss and immersing them in 5% solutions of magnesium sulfate (MgSO 4 ) and sodium chloride (NaCl) for 28 days to evaluate weight gain due to salt deposition. Compared with the control mixture, the improved concrete mixture demonstrated superior performance, exhibiting lower weight loss in acid tests and reduced weight gain in salt tests. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses further confirmed the enhanced microstructural characteristics of the optimized mixture, revealing better bonding and distribution of calcium silicate hydrate (CSH) gels. The results validate the potential of using RFA and SS as sustainable alternatives to traditional aggregates, contributing to more durable and eco-friendly concrete solutions. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under the responsibility of International Conference on Structural Integrity Organizers

Keywords: Concrete Durability; Rubber Fine Aggregate; Steel Slag; Chemical Resistance; Structural Integrity

* Corresponding author. Tel.: +91-7358135699. E-mail address: rsrirammohan@srmuniversity.ac.in; rsrirammohan@gmail.com

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under the responsibility of International Conference on Structural Integrity Organizers 10.1016/j.prostr.2025.07.071