PSI - Issue 70

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ScienceDirect

Procedia Structural Integrity 70 (2025) 501–508

Structural Integrity and Interactions of Materials in Civil Engineering Structures (SIIMCES-2025) Influence of High-Volume Fly Ash and Silica Fume on the Behaviour of Self-Compacting Concrete Shashikant Kumar a, *, Nitish Kumar a , Vijay Kumar a , Atul Kumar Rahul a , Akash Priyadarshee a , Md Irfan Ansari b

a Department of Civil Engineering, Muzaffarpur Institute of Technology, Muzaffarpur, 842003, India b Department of Civil Engineering, Government Engineering College, Khagaria, Bihar, India

Abstract Researchers are being forced to examine the performance characteristics of cement concretes with different mineral admixtures in an attempt to prolong the lifespan of buildings under extreme exposure situations. Furthermore, the need to lower the carbon dioxide emissions from the production of cement has made the use of substitute binding materials more important. Recently, there has been a noticeable increase in the usage of nanoparticles in cement concrete to improve performance attributes and decrease pore volume. The purpose of this work is to examine the microstructural, fresh, and hardened properties of combinations of high-volume fly ash and silica fume used in self-compacting concrete (SCC). SCMs were added to the mixes in varying amounts to replace the cement. By using various flowability tests such as T-500 time (time to reach 500 mm flow diameter), slump flow, J-ring flow, L-box height ratio, and V-funnel time, the effect on fresh qualities was evaluated. In comparison to a control mix (without SCM), the hardened characteristics of SCC were assessed in terms of compressive and tensile strength. SEM and XRD were used to analyse the microstructural characteristics of mixtures containing large amounts of SCMs. It was found that adding FA enhanced SCC's newly discovered qualities. The use of SCMs resulting in a 5% increase in compressive strength over the control mix. Silica fume had the most significant positive effect on the mechanical and microstructural properties of SCC at all stage of curing ages. © 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: High-volume fly ash; Silica fume; Self-compacting concrete; X-ray diffraction; Scan electron microscopic image

* Corresponding author. Tel.: +91-9097333370. E-mail address: shashikant.ce15@nitp.ac.in

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.2025.07.083