PSI - Issue 83

Samia M. Mohamed et al. / Procedia Structural Integrity 83 (2026) 72–78

76

Electric al conduct ivity (S/cm)

Sensing sensitivity

Raw materials

Conductive fillers

Electrical resistivity (Ω· cm)

Remarks

Reference

SS (%/M Pa)

Solid

Liquid

Type

Content

FCR (%)

GF

wt%

(200°C) 48 (400°C) FCR ↑ when filler content ↑ Piezoresis tivity ↓ at small strain; moisture sensitivity ↓ due to hydropho bic phase. Sensitivity ↑ with NCB; capable of detecting initial crack and final failure

3.4

Filler type and dosage control sensitivity vs. strength trade-off.

Lee et al., (2022)

UHPFR C

CB, NP, GP, SSP

5, 10 wt%

—

—

Water

—

—

A hydrophobic additive stabilizes

Water+ admixtu res

2%GNP + 1% SHP

Dong et al., (2022)

OPC+ SF

GNP+ SHP

the electrical signal against moisture.

—

—

—

—

Low NCB → weak signal, higher NCB → network rearrangement/rec onstruction → sensitivity ↑ .

0–6.0 wt% (binder)

GGBS+ SF + MK

Wang et al., (2025)

KOH+ K 2 SiO 3

NCB

—

—

—

—

under comp.

0.0016, 0.0099, 0.0526, for 2:1, 1:2, 0:3, respecti vely.

6.08, 1.01, 0.19, for 2:1, 1:2, 0:3, respectively .

Tot = 4.5, 9% BC: NCB= 3:0, 2:1, 1:2, 0:3

BC+NC hybrid→ workability ↓ as total carbon ↑; Resistivity ρ ↓ as total carbon ↑ .

FCR ↑ with the cycles/da mage.

Kang et al., (2024)

OPC+ biochar

Water+ SP

BC+ NCB

—

—

FCR: Fractional change in resistivity, SS: Stress sensitivity, GF: Gauge factor, GGBS: Ground granulated blast slag, NCB: Nano-carbon black, fc': Compressive strength, f t : Flexural strength, NCP: Nano-carbon powder, POM fiber: Polyoxymethylene fiber, SP: Superplasticizer, SF: Silica fume, CMF: Carbon micro-fiber, ITS: Indirect tensile strength, FAC: Fly ash cenosphere, RM: red mud, CB: Carbon black, CNF: Carbon nano fiber, NP: Nickel powder, GP: Graphite, SSP: Steel-slag powder, GNP: Graphite nano-powder, SHP: Silicone hydrophobic powder, BC: Biochar Integration challenges include scaling up mixing and casting processes to ensure homogeneous filler distribution across large pavement areas, managing higher material costs, and protecting electrode wiring and sensors from harsh environments. Current field applications are limited, and widely adopted standards for construction and calibration are lacking. To move the technology forward, research should focus on cost-effective fillers and new dispersion methods, robust durability studies under real traffic and environmental conditions, and the development of standardized installation and signal-interpretation protocols. 3. Conclusions Self-sensing cementitious composites (SSCCs) enable embedded, distributed monitoring in pavements and bridge decks by forming conductive networks whose resistivity/impedance changes with strain, cracking, moisture, temperature, and traffic/loading. Using conductive fillers such as carbon nanotubes, carbon black, graphene derivatives, and steel/metal fibres, these systems act as material-level sensors interrogated through resistance or AC-impedance methods, with electrode layout