Synergistic Use of Nanosilica and Basalt Fibers on Mechanical Properties of Internally Cured Concrete with SAP: An Experimental Analysis and Optimization via Response Surface Methodology

Said Mirgan Borito ¹

Han Zhu ²

Yasser E. Ibrahim ³

Sadi I Haruna ³

Bo Zhao ^{1, 2}

Hide authors affiliations

School of Civil Engineering, Tianjin University, Tianjin 300350, China |

Key Laboratory of Coast Civil Structure Safety of the Ministry of Education, Tianjin University, Tianjin 300350, China |

Engineering management Department, College of Engineering, Prince Sultan University, Riyadh 11586, Saudi Arabia |

Publication type: Journal Article

Publication date: 2025-02-26

MDPI

Journal: Fibers

scimago Q2

SJR: 0.691

CiteScore: 7.0

Impact factor: 4

ISSN: 20796439

DOI: 10.3390/fib13030025

Copy DOI

Abstract

This study explores the combined effects of nanosilica (NS) and basalt fibers (BF) on the mechanical and microstructural properties of superabsorbent polymer (SAP)-modified concrete. NS (0–1.5% replaced by cement weight) and BF (0–1.2% by volume fraction) were incorporated to optimize compressive, flexural, and split-tensile strengths using response surface methodology. Digital Image Correlation (DIC) was employed to analyze failure mechanisms. Results show that while SAP alone reduced strength, the addition of NS and BF mitigated this loss through synergistic microstructure enhancement and crack-bridging reinforcement. The optimal mix (0.9% NS and 1.2% BF) increased compressive, flexural, and split-tensile strengths by 15.3%, 10.0%, and 14.0%, respectively. SEM analysis revealed that NS filled SAP-induced pores, while BF limited crack propagation, contributing to improved mechanical strength of SAP-modified concrete. This hybrid approach offers a promising solution for durable and sustainable concrete pavements.