Journal of building engineering最新文献_第9页

Behavior of square concrete columns subject to small eccentric loading reinforced with Grade 600 MPa steel bars 用600mpa钢筋加固小偏心荷载作用下方形混凝土柱的性能

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-13 DOI: 10.1016/j.jobe.2026.115524

Licheng Ma , Qingxuan Shi , Ling Ma , Jialing Che , Zhanwu Ma , Yan Ma

To research the behavior of square concrete columns subject to small eccentric loading reinforced with Grade 600 MPa steel bars, and ascertain the compressive service strength of Grade 600 MPa steel bar, a total of nine corbel HSRC columns were constructed and tested. Buckling behavior of Grade 600 MPa steel bar subject to compression was considered. A novel stirrup configuration was conceived and employed in these columns. Test variables conducted in this investigation mainly include the stirrup ratio, longitudinal reinforcement ratio, stirrup strength and spacing. The behaviors of HSRC columns were analyzed and discussed under small eccentric compression, such as failure mode, load-deflection relationship, load versus strain of longitudinal bar relationship, load carry-capacity and the evolution of bending moment and curvature. To guarantee the satisfactory mechanical behavior of HSRC columns subjected to small eccentric loading and ensure that Grade 600 MPa steel bar can develop its full plastic strength, stirrup spacing should not exceed 5D, where D refer to as a diameter of longitudinal reinforcing bar. Simultaneously, to further understand the behavior of HSRC columns subjected to small eccentric loading, a suitable Finite element model was established and verified by test results. Based on the test results and the numerical analysis, the compressive service strength of Grade 600 MPa steel bar is recommended as 570 MPa. Finally, to precisely predict the load carry-capacity, a practicable method was proposed by considering the confinement effect.

为研究600mpa钢筋配筋方形混凝土柱在小偏心荷载作用下的受力性能，确定600mpa钢筋的抗压使用强度，共施工试验了9根钢柱。研究了600 MPa级钢筋在压缩作用下的屈曲行为。一种新颖的马镫结构被设想并应用于这些柱子中。试验变量主要包括箍筋比、纵向配筋比、箍筋强度和间距。分析和讨论了小偏心受压下HSRC柱的破坏模式、荷载-挠度关系、纵杆荷载-应变关系、承载能力以及弯矩和曲率的演变规律。为保证HSRC柱在小偏心荷载作用下的满意力学性能，保证600mpa级钢筋充分发挥塑性强度，箍筋间距不应超过5D，其中D为纵筋直径。同时，为了进一步了解HSRC柱在小偏心荷载作用下的受力特性，建立了合适的有限元模型，并通过试验结果进行了验证。根据试验结果和数值分析，推荐600mpa级钢筋抗压使用强度为570mpa。最后，为了准确预测承载能力，提出了一种考虑约束效应的实用方法。

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引用次数: 0

Modeling and identification of multi-stage thermal inertia for reliable MPC in high-inertia water-based HVAC systems 高惯量水基HVAC系统可靠MPC多级热惯量建模与辨识

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-14 DOI: 10.1016/j.jobe.2026.115620

Shuaihao Jiang , Huihui Song , Meng Liu , Fanqiang Meng , Liang Liu , Yanbin Qu

Water-based HVAC systems exhibit strong thermal inertia distributed across the heat source, hydronic network, and building envelope, which can significantly affect model predictive control (MPC) performance if not properly represented. This paper develops a unified, control-oriented model that explicitly captures multi-stage thermal inertia into a linear state–space framework. A plant-side identification workflow is proposed that estimates the source time constant and network delay–attenuation using only routinely available supply and return water temperatures from an air-source heat pump district heating system (ASHP–DHS). The identified parameters are then embedded into an MPC formulation that regulates indoor temperature while limiting electrical power use and actuation variability. Closed-loop simulations compare four MPC configurations with different levels of inertia awareness. Results show that network-side inertia is the dominant factor for warm-up and cooldown behavior: neglecting distribution delay and attenuation leads to longer recovery times and larger temperature-tracking errors. Source-side inertia mainly shapes short-term electrical power ramps, with strong sensitivity when the source time constant is comparable to the control interval. Parameter sweeps further quantify how performance degrades as inertia parameters are mis-specified, providing practical guidance on when explicit multi-stage inertia modeling is essential for reliable control.

水基HVAC系统表现出强烈的热惯性，分布在热源、流体网络和建筑围护结构上，如果没有适当的表示，这可能会显著影响模型预测控制（MPC）的性能。本文开发了一个统一的、面向控制的模型，该模型明确地将多阶段热惯性捕获到线性状态空间框架中。提出了一种电厂侧识别工作流程，仅使用空气源热泵区域供热系统（ASHP-DHS）的常规供水和回水温度来估计源时间常数和网络延迟衰减。然后将确定的参数嵌入MPC配方中，该配方可以调节室内温度，同时限制电力使用和驱动变异性。闭环仿真比较了具有不同惯性感知水平的四种MPC配置。结果表明，网络侧惯性是影响预热和冷却行为的主要因素，忽略分布延迟和衰减会导致更长的恢复时间和更大的温度跟踪误差。源侧惯性主要形成短期的电力斜坡，当源时间常数与控制区间相当时，具有很强的灵敏度。参数扫描进一步量化了惯性参数指定错误时性能下降的情况，为明确的多阶段惯性建模对可靠控制至关重要的情况提供了实用指导。

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引用次数: 0

IoT-enabled occupant-in-the-loop MPC for responsive built environment control and its implementation in a living lab 支持物联网的乘员在环MPC，用于响应式建筑环境控制及其在生活实验室中的实施

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-18 DOI: 10.1016/j.jobe.2026.115648

Hanbei Zhang , Jing Zhang , Tianyou Ma , Kan Xu , Fu Xiao , Christian Ankerstjerne Thilker , Henrik Madsen , Rongling Li

The uncertainty and intermittent nature of occupancy patterns pose challenges to effective built environment control, which further complicated by the need to respond to diverse personalized thermal comfort in a varying building environment. Model predictive control (MPC) integrating occupancy information has emerged as a promising approach for enhancing comfort, air quality (IAQ) and energy efficiency. However, implementing the MPC strategy in real-world HVAC systems of existing buildings with conventional control infrastructure to handle diverse comfort preferences, stochastic occupancy disturbances and dynamic thermal responses still faces significant challenges. This study proposes and experimentally implements an IoT-enabled Occupant-in-the-loop (OITL) MPC strategy that advances built environment control through several contributions. First, it incorporates dynamic reference temperature in the OITL-MPC to enable responsiveness to real-time comfort feedback and integrates stochastic occupancy prediction to account for the stochasticity and time-inhomogeneity of occupancy disturbances. Second, this study develops an IoT architecture towards adaptable implementation of the OITL-MPC in existing buildings. Third, the proposed OITL-MPC strategy is implemented in a real-world office living lab featured with highly intermittent occupancy pattern and active occupancy participation. Finally, the study comprehensively evaluates the multi-dimensional performance and benchmarks against two baseline strategies: conventional local control (FIX) and occupancy-based control (OBC). One-month experimental results show that the OITL-MPC achieves (1) 25.3% energy savings against FIX, (2) improved percentage of arrival temperature meeting Grade-I comfort from 23.1% (OBC) to 48.7%, and (3) optimized IAQ by maintaining CO₂ near 800 ppm while reducing per-person fresh air flow rates by 38% against OBC. The results demonstrate the theoretical robustness and practical viability of the proposed IoT-enabled OITL-MPC.

使用模式的不确定性和间歇性对有效的建筑环境控制提出了挑战，在不同的建筑环境中，需要响应不同的个性化热舒适，这进一步复杂化了。集成占用信息的模型预测控制（MPC）已成为提高舒适性、空气质量（IAQ）和能源效率的一种有前途的方法。然而，在具有传统控制基础设施的现有建筑的实际HVAC系统中实施MPC策略以处理不同的舒适偏好、随机占用干扰和动态热响应仍然面临着重大挑战。本研究提出并实验实现了一种支持物联网的乘员在环（OITL） MPC策略，该策略通过几个贡献来推进建筑环境控制。首先，它在OITL-MPC中加入了动态参考温度，以实现对实时舒适反馈的响应，并集成了随机入住率预测，以解释入住率干扰的随机性和时间非均匀性。其次，本研究开发了一种物联网架构，以适应现有建筑中OITL-MPC的实施。第三，提出的OITL-MPC策略在一个具有高度间歇性占用模式和主动占用参与的真实办公生活实验室中实施。最后，该研究综合评估了两种基线策略的多维性能和基准：传统的局部控制（FIX）和基于占用的控制（OBC）。一个月的实验结果表明，与FIX相比，OITL-MPC实现了(1)25.3%的节能，(2)将到达温度达到i级舒适的百分比从23.1% （OBC）提高到48.7%,(3)优化室内空气质量，将二氧化碳保持在800 ppm附近，同时将人均新鲜空气流量降低38% （OBC）。结果证明了所提出的支持物联网的OITL-MPC的理论鲁棒性和实际可行性。

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引用次数: 0

Ontology-driven digital twins for optimized recommissioning of hospital building operations 本体驱动的数字孪生，用于优化医院建筑运营的重新调试

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-18 DOI: 10.1016/j.jobe.2026.115627

August M.S. Thomsen, Jakob Bjørnskov, Muhyiddine Jradi

Optimizing setpoints in non-residential buildings is complex due to multiple competing objectives, such as: energy efficiency, occupant comfort, and cost. This paper presents a multi-objective optimization framework integrated with an ontology-based digital twin for building operation optimization. Using the Non-Dominated Sorting Genetic Algorithm II, the framework balances thermal discomfort, CO₂ levels, and energy costs, using semantic ontology models for building topology definition and component constraints. Applied to a hospital case study, the approach reduced thermal discomfort by 92%, quantified using kelvin-hours, and reduced operational energy costs associated with space heating and ventilation-related electricity consumption by 48%, relative to baseline operation. These results were obtained using a comfort-focused optimal strategy with 73 decision variables selected from the Pareto front. Robustness was confirmed for previously unseen operational periods that exhibited variations in dynamic factors, such as occupancy and weather conditions. Sensitivity analysis identified space temperature setpoints as primary optimization drivers, followed by supplied air temperature. This scalable framework supports building management system recommissioning by mapping results to controllers, suitable for diverse non-residential buildings.

非住宅建筑的设定值优化是复杂的，因为有多个相互竞争的目标，如：能源效率、居住者舒适度和成本。提出了一种结合基于本体的数字孪生模型的多目标优化框架，用于建筑运行优化。该框架使用非支配排序遗传算法II来平衡热不适、二氧化碳水平和能源成本，并使用语义本体模型来构建拓扑定义和组件约束。应用于医院案例研究，该方法减少了92%的热不适，使用开尔文小时进行量化，与基线操作相比，与空间供暖和通风相关的电力消耗相关的运营能源成本降低了48%。这些结果是使用从帕累托前沿选择的73个决策变量的以舒适为重点的最优策略获得的。鲁棒性在以前未见过的运行期间得到了证实，这些运行期间表现出动态因素的变化，如占用率和天气条件。灵敏度分析确定空间温度设定值是主要的优化驱动因素，其次是供气温度。这种可扩展的框架通过将结果映射到控制器来支持建筑管理系统的重新调试，适用于各种非住宅建筑。

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引用次数: 0

Improving interlayer adhesion of 3D printed concrete by filament interlocking 通过长丝互锁提高3D打印混凝土的层间附着力

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-21 DOI: 10.1016/j.jobe.2026.115700

Longsheng Wang , Zili Huang , Giang D. Nguyen , Murat Karakus

A pivotal limitation of 3DPC - 3D printed concrete is the weak bond strength between filaments and layers due to the layer-by-layer fabrication process. In this research, the mechanical properties of printing filaments were investigated and developed to enhance bond strength in both the vertical and horizontal directions. Rectangular self-interlocked filaments fabricated by specifically designed nozzles were used to enhance bond strength between vertical layers. The improvement of bond strength between horizontal filaments on the same plane was obtained by controlling printing trajectories. The effectiveness of self-interlocking filaments was evaluated by printing and testing four types of 3DPC specimens: two with flat and straight interlayers, and two with interlocked interlayers. The disc specimens cut from printed beams and blocks were subjected to indirect tensile tests with different angles between loading and printing directions. The present study employed an advanced testing method, AUSBIT - Advanced Universal Snap-Back Indirect Tensile testing method, in conjunction with both AE - Acoustic Emission and DIC - Digital Image Correlation to capture not only the tensile strength but also to investigate the fracture resistance and post-peak behaviour of 3DPC specimens. The results showed that the indirect tensile strength between layers increased by 48.35 % when tested at a loading angle of 0-degree using a rectangular interlocking pattern, while the zigzag interlocking pattern resulted in a 60.26 % improvement in bond strength between horizontal filaments, compared with the control specimens. The use of lateral displacement control in Brazilian disc tests helped stabilise the fracture process and enabled a reliable analysis of the intrinsic mechanism governing the evolution of fracture and its influence on the overall snapback behaviour. The promising results reveal great potential for further investigation in this direction for strengthening 3D-printed structures.

3DPC - 3D打印混凝土的一个关键限制是由于逐层制造过程导致细丝和层之间的粘结强度较弱。在这项研究中，研究和开发了印刷长丝的力学性能，以提高垂直和水平方向的结合强度。采用特殊设计的喷嘴制作矩形自锁长丝，以提高垂直层之间的粘结强度。通过控制打印轨迹，提高了同一平面上水平细丝之间的结合强度。通过打印和测试四种类型的3DPC样品来评估自互锁长丝的有效性：两种是平面和直线夹层，两种是互锁夹层。采用不同加载角度和打印方向对打印梁和块切割成的圆盘试样进行间接拉伸试验。本研究采用了一种先进的测试方法，AUSBIT - advanced Universal Snap-Back间接拉伸测试方法，结合AE - Acoustic Emission和DIC - Digital Image Correlation，不仅可以捕获拉伸强度，还可以研究3DPC试件的断裂抗力和峰后行为。结果表明：当加载角度为0°时，采用矩形联锁模式，层间间接抗拉强度比对照试件提高48.35%；采用之字形联锁模式，水平细丝间的粘结强度比对照试件提高60.26%；在巴西压裂盘测试中，侧向位移控制的使用有助于稳定压裂过程，并能够可靠地分析裂缝演变的内在机制及其对整体回弹行为的影响。这一有希望的结果显示了在这一方向上进一步研究增强3d打印结构的巨大潜力。

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引用次数: 0

Experimental investigation of rate-of-loading effects on light wood frame connections and shear walls 轻型木结构连接与剪力墙的加载速率效应试验研究

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-21 DOI: 10.1016/j.jobe.2026.115701

Jianan Chen , Chao Zhang , Frank Lam , Minghao Li , Benoit P. Gilbert , Hong Guan

This study investigates the influence of simulated seismic and wind loading rates on the performance of light wood frame connections and full-size shear walls. Monotonic and reversed-cyclic tests were conducted on sheathing-to-stud connections, hold-down connections, and light wood frame shear walls. For each configuration, density-matched specimens were tested under two loading rates: a regular rate producing failure within approximately 2–10 min, and a higher rate representative of seismic and wind demands, producing failure within 1–10 s. The results show that sheathing-to-stud connections and shear walls exhibit notable increases in peak resistance under the higher loading rate, with average increases ranging from 8% to 14%. In contrast, hold-down connections displayed no statistically significant differences between the two loading-rate conditions, and in some cases, slightly lower strengths were recorded at higher rates. The dominant failure mechanisms remained unchanged across loading rates. Based on the experimental findings, an adjustment to the duration-of-load (DOL) factor is recommended to better reflect the short-term strength of sheathing-to-stud connections and shear walls under seismic and wind loading conditions.

本研究探讨了模拟地震和风荷载率对轻型木框架连接和全尺寸剪力墙性能的影响。对护套-栓钉连接、压紧连接和轻型木框架剪力墙进行了单调和反循环试验。对于每种配置，密度匹配的试件在两种加载速率下进行了测试：一种是在大约2-10分钟内产生破坏的常规速率，另一种是在1-10秒内产生破坏的较高速率，代表地震和风力需求。结果表明：在较高的加载速率下，护柱连接和剪力墙的峰值阻力显著增加，平均增幅为8% ~ 14%；相比之下，按住连接在两种加载速率条件下没有统计学上的显著差异，在某些情况下，在较高的加载速率下记录的强度略低。主要的破坏机制在不同加载速率下保持不变。根据试验结果，建议调整荷载持续时间（DOL）因子，以更好地反映地震和风荷载条件下护柱连接和剪力墙的短期强度。

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引用次数: 0

On the sustainability of digital construction: Whole building life cycle carbon emissions according to three construction techniques 论数字化建筑的可持续性：基于三种施工技术的建筑全生命周期碳排放

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-20 DOI: 10.1016/j.jobe.2026.115663

Francesca Lolli , Bungane Mehlomakulu , Hessam AzariJafari , Randolph Kirchain , Sean Monkman

The sustainability of 3D printed concrete (3DPC) construction is under-explored. This study evaluates the life cycle carbon emissions of 3DPC, stick-frame (STF), and concrete masonry unit (CMU) construction. Two home layouts were modeled across four U.S. climate zones with varying humidity conditions over service lives of 75 and 100 years. The findings reveal that 3DPC homes demonstrate a lower carbon footprint than those built with conventional methods. Over 100 years, embodied carbon in 3DPC homes is 10% lower than CMU and 5% lower than STF, with annual operational carbon savings ranging from 2% to 13%, depending on the climate. Estimated total carbon savings are 8% to over 15% compared to CMU, and 3% to 9% compared to STF. These results are specific to the chosen finishes, a materially efficient 3DPC wall design and low carbon 3DPC material. 3DPC construction can offer a scalable housing solution with a reduced environmental impact.

3D打印混凝土（3DPC）建筑的可持续性尚未得到充分探索。本研究评估了3DPC、stick-frame （STF）和混凝土砌体单元（CMU）建筑的生命周期碳排放。在75年和100年的使用寿命期间，模拟了美国四个气候带的两种住宅布局，湿度条件不同。研究结果显示，与传统方法建造的房屋相比，3d打印房屋的碳足迹更低。在100年的时间里，3DPC房屋的隐含碳比CMU低10%，比STF低5%，每年的运营碳节约在2%到13%之间，具体取决于气候。与CMU相比，估计总碳节约8%至15%以上，与STF相比，估计总碳节约3%至9%。这些结果是特定于所选择的饰面，材料效率高的3DPC墙壁设计和低碳3DPC材料。3DPC建筑可以提供可扩展的住房解决方案，同时减少对环境的影响。

引用次数: 0

Retraction notice to ‘Thermal systems energy optimization employing two independent circuits of double vertical ground U-tube with PCM as the backfill material for building’ [J. Build. Eng. 56 (2022) 104752] 关于“采用双垂直地面u型管两独立回路以PCM作为建筑回填材料的热系统能量优化”的撤回通知[建筑工程学报56 (2022)104752]

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-25 DOI: 10.1016/j.jobe.2026.115674

Elias M. Salilih , Nidal H. Abu-Hamdeh , Ahmed Khoshaim , Radwan A. Almasri , S. Mohammad Sajadi , Arash Karimipour

引用次数: 0

Cement nanocomposite with CoFe2O4 nanoparticles and graphite flakes for microwave absorption in X-band frequency CoFe2O4纳米颗粒与石墨片水泥纳米复合材料在x波段微波吸收

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-26 DOI: 10.1016/j.jobe.2026.115725

Vanamoorthy Mariappan , Eliška Křivánková , Milan Masař , Marek Jurča , Michal Machovský , Lukáš Kalina , Jarmila Vilčáková , Ivo Kuřitka , Martin Boháč , Raghvendra Singh Yadav

This study reports the microwave absorption in cementitious composites through the incorporation of graphite flakes (GF) and ultrasonically synthesized spherical cobalt ferrite (CoFe₂O₄) nanoparticles (CF). Composites with 2.5 wt% GF and 7.5 wt% CF were prepared and characterized for their structural, magnetic, mechanical, and electromagnetic properties. The phase purity of CF nanoparticles and the presence of fillers in the cement matrix were confirmed by X-ray diffraction (XRD). The morphology, distribution, and interfacial interactions between the fillers and the cement matrix were examined using field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). Magnetic hysteresis loops revealed a saturation magnetization of 5.8 emu/g for the cement nanocomposite, confirming the retention of some magnetic behaviour of CF in cement matrix. The results demonstrated excellent microwave absorption performance in X-band range, with a minimum reflection loss (RL_min) of −41.9 dB at 10.59 GHz and an effective absorption bandwidth (EAB) of 2.4 GHz (below −10 dB) at a thickness of only 2 mm, corresponding to microwave absorption efficiency of 99.994%. The obtained microwave absorption performance is attributed to the synergistic effects of permittivity and permeability, favourable impedance matching, and high attenuation constant due to the combined dielectric loss from GF and magnetic loss from CF. Despite a slight reduction in mechanical strength compared to the reference, the composite meets standard structural requirements. This work highlights the potential of using conductive and magnetic nanofillers to develop high-performance cementitious composites for X-band microwave absorption applications.

本文报道了石墨薄片（GF）与超声合成球形钴铁氧体（CoFe2O4）纳米颗粒（CF）在胶凝复合材料中的微波吸收。制备了含2.5 wt% GF和7.5 wt% CF的复合材料，并对其结构、磁性、机械和电磁性能进行了表征。通过x射线衍射（XRD）证实了CF纳米颗粒的相纯度和水泥基体中是否存在填料。利用场发射扫描电镜（FESEM）、能量色散x射线能谱（EDS）和x射线光电子能谱（XPS）研究了填料与水泥基体之间的形态、分布和界面相互作用。磁滞回线显示，水泥纳米复合材料的饱和磁化强度为5.8 emu/g，证实了水泥基质中CF的一些磁性行为。结果表明，该材料在x波段具有优异的微波吸收性能，在10.59 GHz处的最小反射损耗（RLmin）为- 41.9 dB，在厚度仅为2mm时的有效吸收带宽（EAB）为2.4 GHz（低于- 10 dB），微波吸收效率为99.994%。所获得的微波吸收性能归功于介电常数和磁导率的协同效应，良好的阻抗匹配，以及GF的介电损耗和CF的磁损耗相结合而产生的高衰减常数。尽管与参考材料相比，复合材料的机械强度略有降低，但符合标准结构要求。这项工作强调了使用导电和磁性纳米填料开发用于x波段微波吸收应用的高性能胶凝复合材料的潜力。

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引用次数: 0

Sand-free olive kernel aggregate mortars for sustainable building applications: Mechanical and hygrothermal characterization 用于可持续建筑应用的无砂橄榄仁骨料砂浆：机械和湿热特性

IF 7.4 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2026-03-01 Epub Date: 2026-02-28 DOI: 10.1016/j.jobe.2026.115755

Nicolò Lo Presti , Kamilia Abahri , Mohamed Soufiane Ghomchi , Paolo Stabellini , Giovanni Castellazzi

This study explores the valorization of Olive Kernel Aggregate (OKA) as a total substitute for mineral sand in cementitious mortars, addressing the critical need for bio-based alternatives in the construction sector. While previous research on sand-free OKA mortars relied on high cement dosages (

> 600 kg / m^{3}

) to ensure mechanical resistance, this approach often compromises the overall sustainability of the composite. To overcome this limitation, this work investigates the mechanical and hygrothermal performance of mortars produced with moderate binder contents (

300 - 500 kg / m^{3}

). The experimental campaign coupled standard mechanical testing and microstructural analysis (SEM, XRD) with an in-depth hygric characterization, including Water Vapor Permeability and Moisture Buffer Value (MBV) assessments. The results reveal that reducing the cement dosage significantly enhances the insulating properties and moisture buffering capacity, achieving an “Excellent” MBV classification according to the NORDTEST protocol. Conversely, increasing the binder content to

400 kg / m^{3}

yields a compressive strength of approximately

13 MPa

, demonstrating that structural adequacy for specific building applications can be attained with significantly lower clinker content than current literature benchmarks. The discussion highlights a clear trade-off between mechanical strength and hygrothermal comfort, suggesting that these sand-free composites are viable for sustainable building applications ranging from lightweight insulating fillers to moderate load-bearing floor screeds.

本研究探讨了橄榄核骨料（OKA）作为胶凝砂浆中矿砂的完全替代品的价值，解决了建筑行业对生物基替代品的迫切需求。虽然之前对无砂OKA砂浆的研究依赖于高水泥用量（600kg/m3）来确保机械阻力，但这种方法通常会损害复合材料的整体可持续性。为了克服这一限制，本工作研究了中等粘结剂含量（300 - 500kg/m3）的砂浆的机械和湿热性能。该试验结合了标准力学测试和微观结构分析（SEM， XRD），并进行了深入的水力学表征，包括水蒸气渗透性和水分缓冲值（MBV）评估。结果表明，减少水泥掺量可显著提高水泥的绝缘性能和湿缓冲能力，达到NORDTEST标准的“优秀”MBV等级。相反，将粘结剂含量增加到400kg/m3，可产生约13MPa的抗压强度，这表明，与目前的文献基准相比，在显著降低熟料含量的情况下，可以实现特定建筑应用的结构充足性。讨论强调了机械强度和湿热舒适性之间的明确权衡，表明这些无砂复合材料在可持续建筑应用中是可行的，从轻质绝缘填料到中等承重地板找平板。

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引用次数: 0