首页期刊导航|Construction & Building Materials
期刊信息/Journal information
Construction & Building Materials
Elsevier Science
Construction & Building Materials

Elsevier Science

0950-0618

Construction & Building Materials/Journal Construction & Building MaterialsSCI
正式出版
收录年代

    Influence of process parameters on the physical and material properties of WAAM steels

    Athina SpinasaBen WeberXin MengRuizhi Zhang...
    141078.1-141078.27页
    查看更多>>摘要：Wire arc additive manufacturing (WAAM) is a metal 3D printing technique that offers the opportunity to fabricate large-scale structural components with high geometric flexibility and reduced material waste. This study aims to investigate the influence of different process parameters and cooling methods on the physical, mechanical and microstructural properties of WAAM steels with a view to assessing their suitability for use in construction. Six WAAM steel plates with nominal thicknesses of 3.5 mm, 5 mm, 8 mm and 12 mm, printed using ER90S-D2 welding wire, different process parameters and active or passive cooling, were examined. A total of 72 tensile coupons extracted at different orientations relative to the print layers with either as-built or machined surface conditions were tested. 3D laser scanning was performed to capture the as-built surface undulations and facilitate the calculation of surface roughness. X-ray computed tomography (XCT) scanning was conducted on selected coupon specimens to examine the printing defects. The tensile testing revealed that the WAAM steels exhibited largely isotropic elastic behaviour, which aligned with the weak crystallographic texture found in the microstructural analysis. The as-built geometry led to notable reductions in strength and ductility, particularly in as-built specimens loaded perpendicularly to the print layers. The results also showed that the thicker WAAM plates generally exhibited lower yield strength due mainly to the slower cooling rate leading to coarser grains, as revealed by the microstructural examinations. High porosity was observed in the XCT scan results of some coupons and was shown to significantly reduce the material ductility. Finally, the adopted active cooling method was found to increase productivity, but to have a minimal effect on the resulting mechanical properties. The presented findings contribute to the understanding of the material behaviour of WAAM steel and its link to the key process parameters.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Advanced compound treatment strategies for brick-concrete recycled aggregates: Focusing on volcanic ash slurry and innovative chemical solution

    Xiaoqian DaiAiqin ShenZiming HeXiaosen Zuo...
    141252.1-141252.25页
    查看更多>>摘要：The recycling of construction waste into brick-concrete recycled aggregates (BCRA) addresses resource conservation needs, yet properties deficiencies hinder its application. While single chemical modification can offer potential solutions by enhancing BCRA to some extent, achieving comprehensive optimization of properties with concurrent enhancements in economic viability and environmental sustainability remains challenging. Accordingly, this study developed compound modification strategies integrating volcanic ash slurry (VAS) with osmotic crystalline waterproofing agents (OCW) or phosphate-induced precipitation materials (PIP). The aggregate properties and concrete strength were investigated to evaluate modification efficiency. Microstructure characteristics was examined to reveal mechanisms, and environmental-economic benefits were assessed. The results indicated that compound treatments neutralized single-treatment drawbacks while amplifying benefits. VAS&OCW outperformed in improving BCRA's water absorption (37.1 %) and crushing value (36.1 %), whereas VAS&PIP exhibited greater efficacy in boosting apparent density. BCRA optimization elevated recycled concrete strength, particularly VAS&OCW achieving a 10.0 % compressive strength increase. Microstructural variation well supported property improvement, wherein VAS&OCW formed gels, rigid-flexible networks, and hydrophobic films through interactions between their components to enhance BCRA. VAS&PIP improved BCRA properties through hydroxyapatite induced by inter-modifier reactions. VAS&OCW-modified concrete exhibited higher strength-ecology and strength-cost efficiencies, demonstrating greater environmental-economic benefits. These findings are significant for advancing BCRA utilization.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    A multiscale model for predicting the Young's modulus and the thermal-expansion coefficient of concrete at high temperatures

    Simon PetersGiao VuGuenther Meschke
    141259.1-141259.14页
    查看更多>>摘要：A semi-analytical micromechanical model is proposed to predict the evolution of the Young's modulus and thermal-expansion coefficient of concrete at elevated temperatures, considering three scales of observation, namely cement paste, mortar and concrete. After validation with various experimental data sets, the model quantifies different sources of damage to concrete at elevated temperatures, indicating that the chemical decomposition of cement paste has a minor influence on the evolution of the Young's modulus, while the thermal degradation of the aggregate plays a major role. At higher temperatures, cracking is the main mechanism driving the reduction of the Young's modulus of the investigated concretes. With regard to the thermal-expansion coefficient evaluated at multiple scales, load-induced thermal strains highly effect the homogenized total strains at the mortar level. Moreover, it is demonstrated that the dehydration degree of C-S-H increases proportionally with the measured load-induced thermal strains.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Hexagonal, hollow and perforated concrete units reinforced with GFRP bars: Experimental and FEM analysis

    Mohammadamin MirdarsoltanyZahid HussainNima KhodadadiAntonio Nanni...
    141353.1-141353.18页
    查看更多>>摘要：Preserving coastal areas is crucial due to their high population density and economic significance. This study introduces SEAHIVE®, an innovative approach to optimizing man-made coastal protection structures. SEA-HIVE® consists of hexagonal, hollow, and perforated concrete units reinforced with glass fiber-reinforced polymer (GFRP) bars to enhance energy dissipation, structural capacity, and habitat preservation. Experimental tests and finite element model (FEM) analyses were conducted to evaluate performance under transverse compression and flexure. In transverse compression tests, initial cracking occurred at 73-79 kN loads, with ultimate failure loads reaching 143-179 kN. Flexural tests revealed initial cracking at 156 kN, with ultimate loads of 222-250 kN, limited by inadequate reinforcement anchorage and toe crushing. FEM results closely matched experimental data, with compressive capacities predicted at 178 kN and flexural capacities at 261 kN. The study highlights SEAHIVE®'s potential for sustainable coastal protection while identifying areas for design improvement, including enhanced reinforcement detailing and optimized fabrication methods. Additionally, a parametric study was conducted using FEM to evaluate the effects of perforation size, reinforcement ratio, and concrete compressive strength on the structural capacity and crack propagation behavior of SEAHIVE® units, providing insights for optimizing design parameters.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Aqueous carbonation of EAF steel slag to produce Supplementary Cementitious Material: Effects on mineral composition, hydration reactivity and mechanical properties

    Francesca BonfanteGiuseppe FerraraPedro HumbertDavide Garufi...
    141361.1-141361.16页
    查看更多>>摘要：This study investigates the reactivity of Electric Arc Furnace (EAF) slag after direct aqueous carbonation, aiming to identify possible mechanisms to qualify it as a Supplementary Cementitious Material (SCM). To this end, pastes and mortars comprising 10, 20 and 30 % of non-carbonated and carbonated EAF slag were prepared. Compressive strength, isothermal calorimetry, bound water and portlandite consumption tests were performed to ascertain whether the EAF slag can be defined as SCM, and to compare its mechanical and hydraulic properties with those of more conventional SCMs. The CO_2 content of the EAF slag after carbonation was 8.6 %. With the R calorimetric test, a certain hydraulic reactivity of the as-received and hydrated EAF slag was detected while only a small residual reactivity for the carbonated slag was evidenced. However, the bound water and the portlandite consumption tests suggested a higher reactivity of the carbonated slag. The compressive strength test after 28 days showed that the mortar replaced with 30 % carbonated EAF slag (EAFC-30) developed higher strength than those replaced with 30 % of as-received (EAFAR-30) or hydrated (EAFHY-30) slag. The compressive strength tests at 3, 7 and 28 days showed a retarded hydration of EAFC-30 compared to EAFAR-30. The slow but significant hardening of the EAFC-30 mortars agreed with the previous tests and compared to the behaviour of the EAFAR-30 samples, indicates that pozzolanic reactions were more prevalent after the carbonation. Finally, a comparative analysis of CO_2 emissions, substitution percentage and strength class was conducted, confirming carbonated EAF slag as a viable solution.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Evaluating the performance of Bamcrete panels at ambient and elevated temperature

    Anu BalaSupratic GuptaVasant Matsagar
    141363.1-141363.13页
    查看更多>>摘要：In the present study, four types of Bamcrete panels have been fabricated using twin layers of bamboo mesh and four different core materials, namely; glass wool fiber (GWF)-reinforced self-compacting mortar (SCM), styro-foam sheet, rubberized mortar and weaved half-split bamboo. Bamcrete panels were cast using GWF-reinforced SCM to avoid spalling of covering material at elevated temperatures. The core materials have shown a significant effect on the physical and mechanical performance of Bamcrete panels. The insertion of styrofoam sheet as a core material resulted in lowest thermal conductivity of 0.11 W/mK, whereas filling of GWF-reinforced SCM as a core material resulted in highest thermal conductivity of 0.53 W/mK for the Bamcrete panels. From the rebound hammer test, similar values of compressive strength for all the panel surface were obtained because of the same covering material. Bamcrete panels were tested under concentrated load at ambient and elevated temperature up to 600℃. At ambient temperature, the highest load-bearing capacity under concentrated load was obtained as 83 kN for Bamcrete panel (1) having GWF-reinforced SCM in the core area, whereas the lowest load-bearing capacity of 39 kN was taken by Bamcrete panel (2) having styrofoam sheet in the core area. Bamcrete panel (3) with rubberized mortar and panel (4) with weaved half-split bamboo filled with SCM have shown the peak load-bearing capacity of 74 kN and 76.5 kN, respectively. Bamcrete panel (4) has reflected the highest stiffness among all the panels. At elevated temperature, there was a significant loss in peak load capacity of Bamcrete panels. The maximum load taken by Bamcrete panels (1), (2), (3) and (4) after the heating at 400℃ for a duration 60 min. inside an electric furnace were 47.2 kN, 22 kN, 37 kN, and 42 kN, respectively. The peak load capacity of panels (1) and (4) after heating at 600℃ for 60 min. were remained as 33 kN and 31 kN, respectively. There was no charring of bamboo mesh during testing up to the temperature of 400℃, however, styrofoam sheet was burnt out in Bamcrete panel (2) during testing at elevated temperature of 400℃. The bamboo mesh was partially charred only at the top side during testing at 600℃, but no charring has occurred at bottom side of the Bamcrete panels.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    End-of-life performance of hydrophilic and hydrophobic silica aerogel for window applications: Experimental characterization, lighting performance and electricity consumption simulations

    Francesca MerliElisa BelloniCostanza Vittoria FioriniAnn M. Anderson...
    141378.1-141378.15页
    查看更多>>摘要：This paper provides an overview of the 20-yr natural service life of hydrophilic and hydrophobic silica aerogels employed in transparent glazing systems. Hydrophilic aerogels, despite their higher transparency, tend to absorb moisture over time, which can degrade their performance, whereas hydrophobic aerogels are water-repellent but exhibit lower optical performance. To investigate the long-term performance of the aerogel samples, a specific artificial aging methodology combining temperature and solar radiation effects was employed. The samples tested for hydrophobicity, porosity, optical, acoustic, and color rendering properties were re-evaluated by means of experimental characterizations after two aging steps: at 12 years (achieved in approximately 120 days) and at 20 years (reached after additional 112 days). Aging has a slight negative effect on the optical properties of the aerogel material, particularly for the more hydrophobic samples (visible transmittance τ_v=0.37 before aging and τ_v=0.30 after 20 years). These samples also exhibit the highest color shift, although the behavior is stable over time; over the 20 year period, the color rendering index decreases by only 2 points compared to 18 and 11 for the less hydrophobic and hydrophilic samples, respectively. Gray tones are not affected by aging, whereas blue-azure colors with high B coordinates experience the most significant deterioration. Acoustic performance is also slightly negatively impacted by aging; however, sound insulation remains very good, with high transmission loss values (up to 30 dB for hydrophilic aerogel and up to 25 dB for hydrophobic aerogel). No significant changes were detected in surface area, pore distribution, and infrared spectra, suggesting stability; however, the aerogels that initially exhibited hydrophobic properties lost their hydrophobicity, due to a structural modification. The experimental data were subsequently implemented in dynamic simulations to evaluate the annual electricity consumption for different types of aerogel glazing systems. The simulations have demonstrated satisfactory illumination conditions in a case study office, regardless of the level of hydrophobicity. The aging process has a negligible effect on the electricity consumption for artificial lighting, with a 6-8 % increase after 20 years, and aerogel glazings effectively prevent glare for the occupants.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Performance and synergistic mechanism of bio-oil/lignin composite modified asphalt based on molecular dynamics

    Yi ZhangChundi SiYanshun JiaTianwang Li...
    141392.1-141392.16页
    查看更多>>摘要：For enhancing the comprehensive properties of asphalt, increasing the recovery of waste resources, decreasing the financial burden and increasing the reliance on petroleum-based materials, bio-oil/lignin composite-modified asphalt (OLMA) is a promising binder material. In this work, the chemical properties and molecular behaviors of OLMA were characterized to explore the synergistic mechanism between bio-oil and lignin via Fourier transform infrared spectroscopy, thin-layer chromatography, and molecular dynamics simulations. Both bio-oil and lignin increased the aromatic index (C=C bond), by 8.51 % and 46.81 %, respectively, while showing little effect on the long chain index (-(CH_2)_(n~-), n ≥ 4) and different effects on the aliphatic index (C-H bond in -(CH_2)_(n~-) and -CH_3). The addition of bio-oil increased the saturate and aromatic contents and reduced the resin and asphaltene contents of the asphalt, whereas the addition of lignin significantly increased the aromatic and resin contents and decreased the saturate content but had no significant effect on the asphaltene content. With the addition of 10 % bio-oil or 20 % lignin, Isolgel decreased by 16.87 % and increased by 9.64 %, respectively, compared with that of virgin asphalt. Molecular structure models of the bio-oil-lignin-asphalt system were constructed and validated, revealing the mechanism by which bio-oil/lignin influences the molecular behavior of the asphalt system by restricting the molecular diffusion ability, increasing the intermolecular interaction energy and increasing the solubility coefficient. This study is beneficial for the development of more efficient biobased binders through molecular structure optimization and performance prediction.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Floor heave controlling method for high-speed railway tunnels using a foamed concrete compressible layer

    Hongming TianHaowen CaoWeizhong ChenXianjun Tan...
    141406.1-141406.14页
    查看更多>>摘要：Floor heave in railway tunnels, caused by the time-dependent behavior of soft rock, poses a significant threat to the safe operation of high-speed trains. Based on the yielding support principles, the compressible layer is a potential solution to address the time-dependent floor heave in railway tunnels. However, suitable materials for the compressible layer haven't been developed. In this study, an innovative foamed concrete-filled polyethylene pipe (FC-PEP) is proposed for use as the compressible layer. First, the high compression capability of FC-PEP and its response to long-term train load action were investigated by series of compression tests. The tests results revealed that the stress-strain curves of FC-PEP exhibited an evident stress plateau stage prior to densification, with a maximum compression strain reaching 0.50-0.54 during this stage, which can meet the high compression capability requirement of compression layer. Furthermore, when the density of FC-PEP ranges between 600 and 750 kg/m~3 , the long-term dynamic train load has little impact on its high compression capability, indicates its feasible for controlling floor heave. Finally, based on the monitoring data of floor heave in a railway tunnel, the performance of the FC-PEP layer was investigated through numerical simulations. The numerical results indicate that if a 20 cm thick FC-PEP compressible layer is constructed between the primary support and secondary lining, can reduce floor heave in the railway tunnel by 33.0 %, thereby demonstrating the feasibility of the FC-PEP layer as an effective solution.
      原文链接:
    • NETL
    • NSTL
    • Elsevier

    Study on bending properties of double-limb C-type light steel partially encased fiber reinforced self-compacting lightweight aggregate concrete composite columns (major axis)

    Jingjun LiZhe LiJiangang NiuDelin Tan...
    141407.1-141407.12页
    查看更多>>摘要：To investigate the mechanical properties of the double-limb C-type light steel partially wrapped fiber reinforced self-compacting lightweight aggregate concrete (FSLC) composite columns under major-axial bending, eight specimens were designed for monotonic loading tests under eccentric compression. Three varying parameters of relative eccentricity, FSLC strength grade, and batten plate spacing were considered. In the experiments, the failure process and morphology of such a new type of composite column were observed, and important data including stress distribution, deformation, ultimate bearing capacity, and load-deformation curves were obtained. Moreover, the influence of relative eccentricity, FSLC strength grade, and batten plate spacing on the ultimate bearing capacity of the specimens was analyzed. The research results showed that the bending failure process and morphology of the double-limb C-type light steel partially wrapped FSLC composite column were similar to those of partially encased steel-concrete (PEC) columns. Depending on the eccentricity, two forms of failure, including large-eccentric loading failure and small-eccentric loading failure, were exhibited. The ultimate bearing capacity of the specimens decreased with the increase of the relative eccentricity, while increasing the FSLC strength grade and decreasing the batten plate spacing can effectively improve the bearing capacity of the specimens. Based on the modified plane section assumption, the formula for calculating the positive sectional ultimate bearing capacity of the section steel double-limb C-type light steel partially wrapped FSLC bending column was derived, and the calculated value was in good agreement with the experimental value.
      原文链接:
    • NETL
    • NSTL
    • Elsevier