Q. B. Bui

Ton Duc Thang University | TDT · Civil Engineering

Graphene (Gr) and Graphene Oxide (GO) are graphene-based nanosheet (GNS) materials with ultrahigh mechanical properties. The addition of Gr/GO (from 0.01% to 2% in mass) to a cement-based material can significantly enhance its mechanical properties. GO has higher efficiency than Gr, but it is more costly. In this paper, a Gr-GO solution was develop...

The construction industry is one of the sectors which have significant impacts on the environment. The research on sustainable materials is a demand of society. This paper presents an investigation on the use of fly ash (FA) geopolymer binder for the production of unburnt bricks. First, an optimisation process for the ratio of alkaline activator so...

The recycling of construction and demolition wastes is important in the circular economy. Numerous studies have been carried out on recycled aggregate concrete (RAC). On the other hand, geopolymer is a promising binder which has less CO2 emission than Portland cement. However, the number of studies on geopolymer recycled aggregate concrete (GRAC) i...

In this work, the biocomposites were manufactured by twin-screw internal mixing at 170oC for 5 minutes with a rotation speed of 60 rpm. The composites sheets were then shaped on a hydraulic press at 185oC. Pore characterization including pore volume fraction, 3D-pore structure and morphology, and pore distribution of these materials were investigat...

Fiber concrete is a technique that has been investigated for several decades, mainly to reduce the cracking problem in certain special reinforced concrete structures. Fiber concrete has recently been investigated for other applications, for example, the complete replacement of steel reinforcement rebars. Several structures have been built without s...

Vietnam is undergoing a continuing construction boom. This enormous volume of new constructions is characterized by simple building techniques and large consumption of materials. The Vietnamese government would like to reduce the use of traditional fired clay bricks to avoid inefficient brick production with high energy use, significant CO2 emissio...

The paper presents an experimental study on the durability of geopolymer stabilised compacted earth (GSCE) samples exposed to various wetting–drying (w-d) cycles at different pH and salt concentration conditions. Compressive strength, splitting tensile strength, weight loss, and moisture content were determined after 1, 3, 6, 9, and 12 w-d cycles....

Earth material is attracting renewed attentions in the context of sustainable development. In several cases, to improve the properties of earth material, cement is added. This paper presents an exploratory investigation on the addition of Graphene Oxide and Graphene (GO-Gr) solution in cement stabilised earth (CSE) material. The GO-Gr are the nanos...

Based on the RILEM Technical Committee 274-TCE work, this paper is a discussion of the remaining engineering challenges faced by earthen architecture. The assessment of earth material performances requires the development of appropriate procedures and standards. This is discussed in particular for the characterisation, hygrothermal behaviour, mecha...

The underground spaces are more than more exploited for constructions, especially in the big cities. One of the problems to be treated for underground structures is the waterproofing. The current technique today for underground levels is using the peripheric reinforced concrete (RC) diaphragm walls and disposes a basement drainage system to evacuat...

Portland cement concrete is a popular construction material but it has high carbon footprint and consumes significant natural resources. Using geopolymer and recycled concrete aggregates is an interesting approach to reduce the carbon footprint, the natural resource consumption. Limited studies in the literature have focused on geopolymer recycled...

Earth is an ancient construction material that is attracting numerous scientific investigations due to the sustainable characteristics of this material and the significant heritage of existing earth constructions. Several studies have recently been conducted to investigate the seismic performance of earth buildings. This chapter presents the state...

This chapter reviews the potential impact of six environmental agents (water, ice, wind, fire, solar radiation and chemical attack) on the long-term stability of earth buildings together with some of the most common techniques for measuring and improving material durability. Liquid water appears the most detrimental of all environmental agents, not...

This book presents the work done by the RILEM Technical Committee 274-TCE. It focuses on the estimation of the parameters which are necessary to properly design earthen constructions. It provides a compilation of the value classically obtained for the key parameters of earthen materials, a pedagogical presentation of the main testing procedures for...

Building with earth is an ancient technique which has been the object of numerous studies during the last decade, due to sustainable properties of the material. To improve the mechanical properties and the durability of earthen material, hydrau-lic binders are usually added (e.g. cement or lime). Other binders with lower carbon footprint are invest...

Starch nanoparticles, synthesized from native starch through the hydrolysis approach, are considered as potential reinforcers to sustainable biodegradable nanocomposite with poly(lactic)acid. Some properties of nanocomposites are upgraded to expand their applications compared to poly(lactic) acid. As relevant, starch nanoparticles are spherically s...

The present study evaluates the performances of a rammed earth (RE) structure under seismic loading and its reinforcement by using finite element simulations. First, the pertinence of the numerical model was evaluated through the simulation of an experimental test conducted on a 0.5-scale house and presented in the literature. A full 3D model, base...

The need for a vast quantity of new buildings to address the increase in population and living standards is opposed to the need for tackling global warming and the decline in biodiversity. To overcome this twofold challenge, there is a need to move towards a more circular economy by widely using a combination of alternative low-carbon construction...

The development of electrocatalyst for large-scale production of hydrogen and oxygen via water electrolysis with low overpotential is highly necessary. In this research, a novel electrocatalyst of sulfur-doped nickel cobalt phosphide nanosheets coating over structure of the conductive carbon cloth (CC) (S-NiCoP/CC) was synthesized via a facile elec...

Ordinary cement concrete is a popular material with numerous advantages when compared to other construction materials; however, ordinary concrete is also criticized from the public point of view due to the CO2 emission (during the cement manufacture) and the consumption of natural resources (for the aggregates). In the context of sustainable develo...

In the context of a circular economy, the recycling becomes more than more important. In the construction industry, the wastes from the destructions of old structures are significant. The recycling of the old concretes can contribute to reduce the extraction of the new natural resources (gravel, sand) and to reduce the waste deposit areas. Numerous...

This paper describes the effect of inorganic adsorbents on the hygrothermal performance of insulating materials. The addition of the inorganic adsorbents leads to significant effect to the microstructure and mechanical properties of these materials. The thermal conductivity rang of the materials containing adsorbents from 0.095 to 0.116 (W/m−1 K−1)...

In this study, the formation of a novel electrocatalyst originated from small Pt nanoparticles attached on surface of zinc phosphide nanosheets was successfully prepared by facile method without the binder usage for hydrogen evolution reaction (HER). The as-prepared catalyst was a highly porous structure with large active surface area, thereby effe...

Electrochemical nonenzymatic sensor has achieved numerous attentions from analytical chemistry communities. A facile and direct synthesis route for developing high-performance electrocatalyst is essential to improve efficiency of sensor in terms of cost and catalytic activities for reliable analysis applications. In this research, we introduced an...

Rammed earth (RE) is a sustainable material which is made by compacting the soil in a formwork. The earthquake performance of RE structures is an important topic, however the out-of-plane seismic behavior of RE structures has not been thoroughly investigated in the literature. The objective of the present paper is to study the out-of-plane seismic...

This study aims to produce novel composite artificial marble materials by bulk molding compound processes, and improve their thermal and mechanical properties. We employed stearic acid as an efficient surface modifying agent for CaCO3 particles, and for the first time, a pretreated, recycled, polyethylene terephthalate (PET) fibers mat is used to r...

The development of anodic catalysts for direct methanol fuel cell applications has recently been concerned in both academy and energy industries. In this study, we successfully developed an efficient electrocatalyst based on ultra-small platinum nanoparticles (Pt NPs) deposited reduced graphene oxide (rGO) supported by a three-dimensional (3D) fram...

Solid State Sciences Volume 101, March 2020, 106143 Hierarchical star-like molybdenum phosphides nanostructures decorated graphene on 3D foam as self-supported electrocatalyst for hydrogen evolution reaction Author links open overlay panelN.T.L.MaiaQ.B.Buid Show more https://doi.org/10.1016/j.solidstatesciences.2020.106143Get rights and conten...

A facile two-step approach has been developed to fabricate blackberry-like gold nanostructure uniformly depositing on surface of reduced graphene oxide/three-dimensional nickel foam (Au-rGO/3DNF). The hybrid material has been successfully applied as a free-standing biosensor for nonenzymatically detecting H2O2 in 0.1 M PBS medium. The results indic...

Rammed earth (RE) is a construction material manufactured by compacting the soil by layers in a formwork. This material has been the focus of numerous scientific researches in the last decades because of its sustainable properties and the heritage of RE buildings throughout the world. Several studies were performed to investigate different aspects...

Rammed earth (RE) is a soil-based construction material which attracts scientific researches because of its sustainable properties. This paper presents a numerical study to investigate the in-plane seismic behaviour of RE walls. First, an in-situ RE wall was modelled by the discrete element method (DEM). The robustness of the model was checked by c...

In this study, we successfully prepared a highly sensitive hydrogen peroxide sensor by directly growing heterostructure of cobalt oxide-sulfide nanosheets on three-dimensional foam. As a self-supporting sensor, it exhibited good activity and excellent stability for hydrogen peroxide detection with a sensitivity of 0.059 mA μM−1 cm−2, wide detection...

Rammed earth (RE) is a construction material manufactured from the soil. This material attracts the attention of numerous scientific investigations during the past decade due to its sustainable properties. The performance of RE buildings under horizontal loadings remains an important topic to be investigated. This paper presents an experimental stu...

Herein, we successfully fabricated a novel nanostructure based on hierarchical urchin-like FeCo oxide supported carbon spheres (FeCo Oxide/CSs) via a two-step hydrothermal method followed by a simple annealing step at 300 °C under air. It was found that such urchin-like FeCo Oxide/CSs structure exhibited superior catalytic activity towards hydrazin...

A novel nanohybrid based on palladium sulfide nanoparticles uniformly dispersing on heterostructure of MoS2/nitrogen-doped graphene (PdxSy-MoS2/N-GR) was developed for catalyzing oxygen reduction reaction in alkaline medium. The nanohybrid demonstrated effectively catalytic performance with a positive onset potential of −0.141 V and half-wave poten...

Here we propose a novel nanohybrid of bimetallic nickel‑tungsten sulfides nanostructures uniformly distributed on nitrogen-doped graphene with efficient ORR performance in 0.1 M KOH electrolyte. The material exhibits high limit current density, positive onset potential (+0.97 V) and half-wave potential (+0.82 V), and a small Tafel slope of 101 mV/d...

The performance of an electrochemical sensor for detecting small biomolecules can be greatly upgraded by properly controlling the chemical nanostructure of electrocatalyst. In this study, we successfully prepared a unique hierarchical three-dimensional nanoarchitecture based on gold nanocrystals supported cobalt nanorods on foam substrate via a fac...

In this study, a biocomposite material derived from rice husk filler (RHF) reinforced for polyvinyl chloride (PVC)/epoxidized natural rubber (ENR) blend was developed. RHF particles obtained as a byproduct from the agricultural industry were used as environmentally friendly fillers. ENR was applied as a plasticizer and compatibilizer to improve the...

In present work, we proposed a novel nanohybrid based on hierarchical molybdenum dichalcogenide nanosheets uniformly assembled over surface of nitrogen-doped graphene (MoS2 NSs/N-Gr) via a facile and cost-effective synthesis approach. The developed material was applied for highly sensitive dopamine (DA) detection. It was demonstrated that the MoS2...

At present, dynamic measurements enable the diagnosis of an existing structure at a global scale (the whole structure), while the identification and assessment of local damage (at each element of the structure) remain to be explored. In this study, diagnosis at a local scale was experimentally investigated on a reinforced concrete (RC) frame struct...

A novel hybrid based on non-precious metal catalysts embedded into nitrogen doped graphene nanosheets was developed for oxygen reduction reaction (ORR) by pyrolyzing a mixture of Ni, Pd salts, nitrogen source, and graphene oxide. Scanning electron microscopy, transmission electron microscopy, Raman spectra, and X-ray photoelectron spectroscopy anal...

A hierarchical nanohybrid based on vertical cobalt oxide nanorods shelled with nickel oxide supported on a three-dimensional foam was prepared by a simple synthetic procedure. The unique nanoarchitecture along with superior conductivity and synergistic effect between components made hybrid become as a sensitive non-binder and free-standing sensor f...

A novel hierarchical heterostructure of molybdenum dichalcogenide nanosheets homogeneously assembled on nitrogen doped graphene layer (MoS 2 NSs/N-doped GR) was successfully developed by an easy and cost-effective strategy. The MoS 2 NSs/N-doped GR was then utilized for accelerating hydrogen evolution reaction (HER) in alkaline medium. It was found...

A hierarchical nanostructure consisting of uniform copper oxide nanowires vertically grown on three-dimensional copper framework (CuO NWs/3D-Cu foam) was prepared by a two-step synthetic process. The uniform CuO NWs anchored onto the 3D foam exhibited outstanding electrocatalytic activity towards hydrogen peroxide reduction due to the unique one‐di...

Rammed earth (RE) is a construction material which is manufactured by compacting soil by layers within a formwork to build a monolithic wall. RE material is the subject of numerous scientific researches during the last decade because of the significant heritage of RE buildings and the sustainable properties of this material: low embodied energy, su...

Rammed earth (RE) is a construction material which is made by compacting the soil in a formwork. This material is attracting the attention of the scientific community due to its sustainable characteristics. Among different aspects to be investigated, the seismic performance remains an important topic which needs advanced investigations. The existin...

We successfully developed a hybrid catalyst based on binary CuFe alloy nanoparticles (NPs) uniformly encapsulated within nitrogen-doped graphene nanosheets (CuFe NPs/N-rGO). The catalyst displayed excellent performance for oxygen reduction in 0.1 M KOH medium. In this context, the catalyst showed an onset potential of +0.99 V (vs. RHE), which is co...

In this study, we developed a novel free-standing sensor based on hierarchical zinc-doped nickel hydroxide nanosheets vertically attached three-dimensional (3D) framework (Zn-doped Ni(OH) 2 NSs/3DF) via a mild and facile hydrothermal reaction for non-enzymatic glucose detection. The Zn-doped Ni(OH) 2 NSs/3DF-based sensor exhibited a good sensitivit...

The fabrication of efficient and durable novel electrocatalysts using a facile and cheap way is a potential approach for real energy conversion technology. In this research, a novel nanohybrid based on iron nickel nanoparticles well attached on nitrogen doped graphene nanosheets (Fe2Ni1 NPs/N-Gr) was synthesized through a simple refluxing strategy...

Small and uniform bimetallic WMoSx nanoparticles well distributed on surface of thin graphene nanosheets (WMoSx-Gr) was prepared and investigated as an effective electrocatalysts for oxygen reduction reaction (ORR) in alkaline electrolyte. This material exhibited highly catalytic activity relative to a commercial Pt/C product. In this context, the...

Herein, we successfully developed a novel three-dimensional framework attached carbon nanotubes deposited with high density of gold nanoparticles (Au NPs-CNTs/3DF) through a facile method. The achieved hybrid with an opened hierarchical network was effectively used as a free-standing sensor for hydrazine detection. The catalytic activity of the pro...

Rammed earth (RE) is a construction material which is manufactured by compacting the soil within a formwork, in superimposed layers. RE is attracting scientific studies because of its sustainable properties : a very low embodied energy and an advantageous living comfort due to a particular benefic hygro-thermal behaviour. Numerous studies have been...

Rammed earth (RE) is a construction material which is manufactured by compacting the soil in a formwork, in different layers. Several recent studies have investigated this material. The seismic performance of RE buildings is an important topic which needs to be carefully investigated. The complex numerical model seems a performant approach to inves...

In this study, a hybrid of titanium dioxide, benzophenone and ethylene vinyl acetate (TiO2-BP-EVA) was used as a novel catalyst to accelerate photo-oxidization reaction of low-density polyethylene (LDPE) film under ambient conditions. The degradation of the LDPE films (thickness of ~25 μm) containing different catalyst concentrations were successfu...

Rammed earth (RE) is one of the different techniques of earth constructions. The RE wall is built by compacting the soil in a formwork, layer after layer (about 10–15 cm thick for each layer). RE buildings are recognized for their very low embodied energy and their positive hygrothermal behaviour. Several recent studies have investigated RE materia...

Thermal power plants (TPP) generates wastes (bottom and fly ashes) which become a serious environmental problem in Vietnam. Indeed, although in several countries fly ash can be used for cement industry, fly ash from actual TPP in Vietnam does not have enough good quality for cement production, because the fly ash treatment phase has not yet include...

A new concept for the soil nail walls is here proposed and validated through experimental and numerical approaches. This process, based on the use of precast elements that are easier to install, is cheaper and more aesthetic than the classical methods, but the main advantage is reducing the cement consumption which conducts to divided carbon footpr...

Rammed earth (RE) is a construction material which is manufactured from the soil. The soil is dynamically compacted at its optimum water content, inside a formwork to build a monolithic wall. The RE wall is composed of several layers, about 10–12 cm thick. In the last decades, RE material has been the focus of numerous scientific researches because...

Beam-column joints are critical regions for reinforced concrete (RC) frames subjected to earthquakes. The steel reinforcement is, in general, highly concentrated in these zones. This is why in many cases, headed bars are used. A headed bar is a longitudinal steel reinforcement whose end has a special button added to reduce the bonding length of the...

The present paper is concerned with the simulation of the Casagrande test carried out on a rammed earth material for wall-type structures in the framework of Limit Analysis (LA). In a preliminary study, the material is considered as a homogeneous Coulomb material, and existing LA static and kinematic codes are used for the simulation of the test. I...

Reducing energy consumption for future buildings using bio-based insulation materials is currently one of the most attractive research pursuits. The specific purpose of this research was to optimize thermo-pressing conditions for new low-environmental-impact bio-insulation fiberboards from bamboo fibers and protein-based bone glues. The microstruct...

In several cases where high quantities of steel reinforcements are needed at reinforced concrete (RC) beam-column joints, headed bars are employed as a solution to facilitate the placing of reinforcement bars. This paper establishes a new formula for the prediction of the shear strength of exterior RC beam-column joints where beam longitudinal rein...

Beam-column joints are commonly considered critic regions for RC frames subjected to earthquake. That is why assessing the beam-column joint capacity is an important topic, especially for structures constructed before the modern seismic design codes, or for buildings in post-seismic situations. Among the in-situ structural assessment methods, the v...