Lei V. Zhang

Hebei University of Technology · School of Civil and Transportation Engineering

The inclusion of microencapsulated phase change materials (MPCM) in construction materials is a promising solution for increasing the energy efficiency of buildings and reducing their carbon emissions. Although MPCMs provide thermal energy storage capability in concrete, they typically decrease its compressive strength. A unified framework for the...

In this study, the self-healing behavior of fiber-reinforced mortars incorporating crystalline additives under various temperatures and relative humidities was investigated. Optical microscopy, scanning electron microscopy with energy dispersive X-ray (SEM–EDS) analysis, were conducted to evaluate and characterize the self-healing. Pre-cracked refe...

The increasing concern for decarbonization calls for sustainable construction materials since carbon dioxide emissions from cement industries account for 8% of the total emissions. Incorporating municipal solid waste into concrete as supplementary cementitious materials (SCMs) is one of the fundamental ways to achieve urban sustainability. Iron ore...

Two types of eco-friendly shape-stabilized phase change materials (SSPCMs) were developed in this study. Biobased PCMs were impregnated into the pore structure of recycled expanded glass granules and coated with silica fume particles using a 4-step vacuum impregnation method. The morphological and thermal properties of the fabricated SSPCMs along w...

The increasing concern for decarbonization and sustainability in construction materials is calling for green binders to partially replace cement since its production is responsible for approximately 8% of global anthropogenic greenhouse gas emissions. Supplementary cementitious materials (SCMs), including fly ash, slag, silica fume, etc., can be us...

As cement manufacturing accounts for 8% of global CO2 emissions, there is an urgent need to tackle the environmental impacts of cement production and address the decarbonization of construction materials. Adopting supplementary cementitious materials (SCMs), including fly ash, slag, silica fume, etc., can be used as a partial replacement for ordina...

Alkali-activated materials (AAMs), usually derived from the activation of industrial by-products, have demonstrated great potential as alternatives to ordinary portland cement (OPC) concrete. However, AAMs are susceptible to cracking due to their inherent brittleness, which may compromise their service life and severely hinder wider acceptance and...

Alkali-activated materials (AAMs) have emerged as promising alternative binders to curb carbon dioxide emissions from portland cement production and decarbonize concrete construction. Wide-ranging research has been undertaken to explore diverse AAMs formulations. However, predicting the engineering properties of AAMs using traditional empirical and...

During their service life, concrete structures are subjected to combined fluctuations of temperature and relative humidity, which can influence their durability and service life performance. Self-healing has in recent years attracted great interest to mitigate the effects of such environmental exposure on concrete structures. Several studies have e...

Eco-efficient concrete produced by alkali-activation of recycled by-products has increased susceptibility to cracking. This study investigates the potential of S. pasteurii bacteria to impart crack self-healing in such green concrete. Porous expanded glass granules made from recycled glass were used, for the first time, as bacterial and nutrient ca...

Conventional cross-laminated timber is an engineered wood product consisting of solid-sawn lumber panels glued together. In this study, the structural behavior of solid wood panels of Nail-Cross-Laminated Timber (NCLT) panels connected with nails instead of glue was studied. The failure mode and nail deformation of the novel NCLT panels under axial...

The potential of crack self-healing in cement-based materials has gained much attention as a strategy to mitigate cracking-induced durability issues. While considerable research efforts have been devoted to crack self-healing in ordinary cementitious systems, there is a dearth of studies on self-healing of alkali-activated materials. In this study,...

In this study, the self-healing behavior of fiber-reinforced mortars incorporating crystalline additives under various temperatures and relative humidities was investigated. Optical microscopy, scanning electron microscopy with energy dispersive X-ray (SEM-EDS) analysis, were conducted to evaluate and characterize the self-healing. Pre-cracked refe...

Phase change materials (PCMs) have been deployed to improve the thermal performance of building materials such as concrete and gypsum. Among various incorporation methods, micro-encapsulated PCMs (MPCMs) have been extensively integrated into cement mortar and concrete owing to their versatility. Nevertheless, some detrimental effects of MPCMs on th...

Strengthening of deficient reinforced concrete (RC) beams using near-surface mounted (NSM) fiber-reinforced polymer (FRP) bars has in recent years been gaining greater interest and increased field applications. While considerable research has explored the behavior of NSM-FRP strengthened rectangular-section RC beams and the effects of influential p...

Using stainless steel (SS) reinforcement can mitigate colossal corrosion damage inflicted to reinforced concrete (RC) structures worldwide. However, there is still dearth of studies on the seismic behavior of SS-RC structures. Hence, quasi-static tests were carried out in this study to explore the seismic performance of three RC frame edge joint sp...

Geopolymers and alkali-activated materials (AAM) have emerged as a promising sustainable alternative to ordinary Portland cement (OPC). Although much effort has recently been devoted to a wide range of research on the self-healing of cracks in OPC-based composites, little is known about the self-healing potential of AAMs. Therefore, this study expl...

Cement production is currently the third largest source of CO2 anthropogenic emissions. To mitigate the associated climate change threats, alkali-activated systems have emerged as a promising cleaner alternative binder. The present study deploys orthogonal experimental design and ANOVA analysis to develop alkali-activated slag (AAS) grouts with ade...

Despite that considerable research has explored self-healing of portland cement-based materials, potential self-healing in alkali-activated binders remains largely unexplored. Therefore, this paper deploys a wide array of experimental techniques to investigate the self-healing properties of PVA fibre-reinforced alkali-activated slag-based composite...

Cross-laminated timber (CLT) is an innovative wood panel composite that has been attracting growing interest worldwide. Apart from its economic benefits, CLT takes full advantage of both the tensile strength parallel to the wood grain and its compressive strength perpendicular to the grain, which enhances the load bearing capacity of the composite....

The commercial application of copper bioleaching, an environmentally-friendly approach for low-grade and secondary mineral resources recycling, has increased worldwide since the 2000s. As the world's second-largest economic entity and the largest developing country, China has the largest demand for metal resources, significantly advancing the theor...

A number of rockburst accidents occurring in soft coal seams have shown that the rockburst mechanism involved in soft coal seams is significantly different from that involved in hard coal seams. Therefore, the method used to evaluate rockburst in hard coal seams is not applicable to soft coal seams. This paper established an energy integral model f...

An investigation was conducted on the overall burst-instability of isolated coal pillars by means of the possibility index diagnosis method (PIDM). First, the abutment pressure calculation model of the gob in side direction was established to derive the abutment pressure distribution curve of the isolated coal pillar. Second, the overall burst-inst...