Table 1 Nanomaterial-modified concrete and their relevance to the present study.

Micro-silica, Nano-

silica, Fly ash

Modified OPC

concrete

Strength &

Microstructure

Mechanical tests,

SEM

Compared NS + micro

fillers; no RSM or

GO⁵

Nano-silica

High-temp resistant

concrete

High temp resistance

& microcracks

TGA, SEM,

porosimetry

Focus on heat

resistance only; single

nano ⁶

Stabilized nano-silica,

Silica fume

High performance

concrete

Dispersion and

strength gain

SEM, modulus

test

Improved Strength

with NS; no GO or

NA⁷

Interface zone (SCI)

Reinforced concrete

SCI prep & nano-

mechanics

SEM, Nano-

indentation

SCI analysis only;

no material

comparison⁸

Nano-SiO₂,

Nano-Al₂O₃

Geopolymer concrete

Kinetics & microstructure

in geopolymer

XRD, SEM,

JMAK model

In geopolymer,

not OPC; limited

comparability9

Nano-TiO₂

Reactive powder

concrete (RPC)

Strength & conductivity

XRD, SEM,

electrical tests

Only NT studied;

no NS/NA/GO

contrast¹⁰

Nano-graphene

Autoclaved aerated

concrete

Strength, impact, and

absorption

SEM, XRD,

mechanical

Specialty AAC

product; not conventional

concrete¹¹

UHPC, Heat curing

Ultra-high-performance

concrete

Curing effects on

microstructure

Nano-indentation,

XRD, SEM

Curing focus in

UHPC, no dosage

optimization¹²

Nano-CaCO₃

UHPC with steel

fibers

Fiber bond & ITZ

BSEM, MIP, fiber

pull-out

CaCO₃ in

UHPC, focus on fiber

bond¹³

Nano-SiO₂, Steel fiber

Steel fiber reinforced

concrete

High-temp

mechanicals, ITZ

XRD, SEM, HT

testing

NS in SFRC; thermal

focus, not multi-

nano¹⁴

Nano-silica, Basalt

fiber

Recycled concrete

Elevated temp

performance

XRD, SEM

Uses NS + fiber in

recycled mix; not

mechanical-durability

balance¹⁵

Nano-silica on RAC

Recycled aggregate

concrete

RAC enhancement

with NS treatment

SEM, physical

pre-treatment

RAC quality improved

by NS; lacks NS vs.

NA vs. GO

study¹⁶