The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review

The interfacial transition zone (ITZ) significantly influences the mechanical properties and durability of lightweight aggregate concrete (LWAC), yet existing research on the ITZ in LWAC remains fragmented due to varied characterization techniques, inconsistent definitions of ITZ thickness and poros...

Full description

Saved in:
Bibliographic Details
Main Authors: Jian Zhou, Yiding Dong, Tong Qiu, Jiaojiao Lv, Peng Guo, Xi Liu
Format: Article
Language:English
Published: MDPI AG 2025-08-01
Series:Buildings
Subjects:
Online Access:https://www.mdpi.com/2075-5309/15/15/2784
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849405491972669440
author Jian Zhou
Yiding Dong
Tong Qiu
Jiaojiao Lv
Peng Guo
Xi Liu
author_facet Jian Zhou
Yiding Dong
Tong Qiu
Jiaojiao Lv
Peng Guo
Xi Liu
author_sort Jian Zhou
collection DOAJ
description The interfacial transition zone (ITZ) significantly influences the mechanical properties and durability of lightweight aggregate concrete (LWAC), yet existing research on the ITZ in LWAC remains fragmented due to varied characterization techniques, inconsistent definitions of ITZ thickness and porosity, and the absence of standardized performance metrics. This review focuses primarily on structural LWAC produced with artificial and natural lightweight aggregates, with intended applications in high-performance civil engineering structures. This review systematically analyzes the microstructure, composition, and physical properties of the ITZ, including porosity, microhardness, and hydration product distribution. Quantitative data from recent studies are highlighted—for instance, incorporating 3% nano-silica increased ITZ bond strength by 134.12% at 3 days and 108.54% at 28 days, while using 10% metakaolin enhanced 28-day compressive strength by 24.6% and reduced chloride diffusion by 81.9%. The review categorizes current ITZ enhancement strategies such as mineral admixtures, nanomaterials, surface coatings, and aggregate pretreatment methods, evaluating their mechanisms, effectiveness, and limitations. By identifying key trends and research gaps—particularly the lack of predictive models and standardized characterization methods—this review aims to synthesize key findings and identify knowledge gaps to support future material design in LWAC.
format Article
id doaj-art-8c4b4e232cc2417e83a8f08f9475df58
institution Kabale University
issn 2075-5309
language English
publishDate 2025-08-01
publisher MDPI AG
record_format Article
series Buildings
spelling doaj-art-8c4b4e232cc2417e83a8f08f9475df582025-08-20T03:36:39ZengMDPI AGBuildings2075-53092025-08-011515278410.3390/buildings15152784The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A ReviewJian Zhou0Yiding Dong1Tong Qiu2Jiaojiao Lv3Peng Guo4Xi Liu5Northwest Engineering Co., Ltd., Xi’an 710065, ChinaSchool of Architectural Engineering, Chang’an University, Xi’an 710064, ChinaNorthwest Engineering Co., Ltd., Xi’an 710065, ChinaNorthwest Engineering Co., Ltd., Xi’an 710065, ChinaNorthwest Engineering Co., Ltd., Xi’an 710065, ChinaSchool of Architectural Engineering, Chang’an University, Xi’an 710064, ChinaThe interfacial transition zone (ITZ) significantly influences the mechanical properties and durability of lightweight aggregate concrete (LWAC), yet existing research on the ITZ in LWAC remains fragmented due to varied characterization techniques, inconsistent definitions of ITZ thickness and porosity, and the absence of standardized performance metrics. This review focuses primarily on structural LWAC produced with artificial and natural lightweight aggregates, with intended applications in high-performance civil engineering structures. This review systematically analyzes the microstructure, composition, and physical properties of the ITZ, including porosity, microhardness, and hydration product distribution. Quantitative data from recent studies are highlighted—for instance, incorporating 3% nano-silica increased ITZ bond strength by 134.12% at 3 days and 108.54% at 28 days, while using 10% metakaolin enhanced 28-day compressive strength by 24.6% and reduced chloride diffusion by 81.9%. The review categorizes current ITZ enhancement strategies such as mineral admixtures, nanomaterials, surface coatings, and aggregate pretreatment methods, evaluating their mechanisms, effectiveness, and limitations. By identifying key trends and research gaps—particularly the lack of predictive models and standardized characterization methods—this review aims to synthesize key findings and identify knowledge gaps to support future material design in LWAC.https://www.mdpi.com/2075-5309/15/15/2784lightweight aggregate concreteinterfacial transition zonemicrostructuremineral admixturenanomaterialssurface treatment
spellingShingle Jian Zhou
Yiding Dong
Tong Qiu
Jiaojiao Lv
Peng Guo
Xi Liu
The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review
Buildings
lightweight aggregate concrete
interfacial transition zone
microstructure
mineral admixture
nanomaterials
surface treatment
title The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review
title_full The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review
title_fullStr The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review
title_full_unstemmed The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review
title_short The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review
title_sort microstructure and modification of the interfacial transition zone in lightweight aggregate concrete a review
topic lightweight aggregate concrete
interfacial transition zone
microstructure
mineral admixture
nanomaterials
surface treatment
url https://www.mdpi.com/2075-5309/15/15/2784
work_keys_str_mv AT jianzhou themicrostructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT yidingdong themicrostructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT tongqiu themicrostructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT jiaojiaolv themicrostructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT pengguo themicrostructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT xiliu themicrostructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT jianzhou microstructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT yidingdong microstructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT tongqiu microstructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT jiaojiaolv microstructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT pengguo microstructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview
AT xiliu microstructureandmodificationoftheinterfacialtransitionzoneinlightweightaggregateconcreteareview