Journal of building engineering最新文献_第9页

Mode-I dynamic fracture evolution and energy dissipation of basalt fiber reinforced reactive powder concrete 玄武岩纤维增强活性粉末混凝土的 I 型动态断裂演化和能量耗散

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.jobe.2024.111011

Dynamic fracture experiments on basalt fiber reinforced reactive powder concrete (BFRRPC) were conducted using notched semi-circular bending (NSCB) specimens, aiming to investigate the Mode-I dynamic fracture characteristics. Based on the split Hopkinson pressure bar (SHPB) and digital image correlation (DIC) systems, this study focused on investigating the dynamic fracture toughness, fracture process zone (FPZ), crack propagation, fractal dimension of fracture path, and energy evolution of BFRRPC with different basalt fiber contents. The results show the basalt fiber break, pull-out and interface fracture in the matrix in the microscopic experiment results, which are the intrinsic reasons for the enhancement of fracture toughness in RPC due to the fiber presence. The increases in fracture toughness of BFRRPC range between 24.7 % and 42.7 %, with a notable enhancement observed when incorporating 1.0 % basalt fiber content. The crack and the FPZ tip of BFRRPC can be located effectively by the method of displacement-strain mixed calibration. The addition of 1.0 % basalt fiber content effectively delays the crack initiation in specimens, with crack initiation occurring earlier as the loading level increases. The CTOD and FPZ tip opening displacement have nothing to do with the loading level. Basalt fibers can lead to relatively lower and stable fractal dimensions of BFRRPC, effectively reducing the cracking degree and increasing the roughness of cracks. Basalt fiber effectively enhances the fracture energy of RPC. The dissipated energy is mainly composed of the energy consumed by the fracture (fracture energy) of BFRRPC, with the overall residual kinetic energy ratio (the ratio of residual kinetic energy to dissipated energy) generally below 1.90 %.

采用缺口半圆形弯曲（NSCB）试件对玄武岩纤维增强活性粉末混凝土（BFRRPC）进行了动态断裂实验，旨在研究其模态-I动态断裂特征。本研究基于分裂霍普金森压力棒（SHPB）和数字图像相关（DIC）系统，重点研究了不同玄武岩纤维含量的 BFRRPC 的动态断裂韧性、断裂过程区（FPZ）、裂纹扩展、断裂路径的分形维度和能量演化。结果表明，在微观实验结果中，基体中存在玄武岩纤维断裂、拔出和界面断裂，这是纤维存在导致 RPC 断裂韧性增强的内在原因。BFRRPC 的断裂韧性提高了 24.7% 到 42.7%，当加入 1.0% 的玄武岩纤维时，断裂韧性明显提高。通过位移-应变混合校准方法，可以有效定位 BFRRPC 的裂缝和 FPZ 尖端。添加 1.0 % 的玄武岩纤维可有效延迟试样的裂纹萌发，随着加载水平的增加，裂纹萌发的时间会提前。CTOD 和 FPZ 尖端张开位移与加载水平无关。玄武岩纤维可使 BFRRPC 的分形尺寸相对较低且稳定，从而有效降低开裂度并增加裂纹的粗糙度。玄武岩纤维可有效提高 RPC 的断裂能。耗散能主要由 BFRRPC 断裂所消耗的能量（断裂能）构成，总体残余动能比（残余动能与耗散能之比）一般低于 1.90%。

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引用次数: 0

Development and validation of intelligent load control for VRF air-conditioning system with deep learning based load forecasting 基于深度学习负荷预测的 VRF 空调系统智能负荷控制的开发与验证

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.jobe.2024.111017

Variable refrigerant flow (VRF) air-conditioning systems have seen significant growth in Asia and its application is expanding globally. Despite the expanded application, most previous studies have focused on developing fault detection and diagnostics to achieve energy-efficient operations than on predicting power consumption. It's very difficult to predict the electrical consumption owing to its complex system configuration and various control strategies. A new control strategy is described for optimal adjustment of the desired target level based on time series forecasting using the optimized sequence to sequence model for VRF systems. Sequence to sequence (seq2seq) model with attention mechanism and Bayesian optimization is developed to predict accurate hourly and daily forecasts and rapid feedback control for fluctuating power consumption for VRF systems. The optimized seq2seq model is integrated into the intelligent load control (ILC). ILC can be used to manage VRF systems by dynamically prioritizing indoor units for curtailment using both quantitative inputs and qualitative rules. Overall, the results demonstrate that the deep learning based control allows coordination of the controllable loads of VRF systems in three commercial buildings. ILC with deep learning manages the power consumption within a desired target level, as well as indoor temperature reflecting the status of controlled indoor units, as objective functions of the control algorithm.

变制冷剂流量（VRF）空调系统在亚洲有显著增长，其应用正在全球范围内扩大。尽管应用范围不断扩大，但以往的研究大多侧重于开发故障检测和诊断技术，以实现高能效运行，而不是预测耗电量。由于其复杂的系统配置和各种控制策略，预测耗电量非常困难。本文介绍了一种新的控制策略，利用 VRF 系统的优化序列到序列模型，在时间序列预测的基础上对所需目标水平进行优化调整。开发了具有关注机制和贝叶斯优化的序列到序列（seq2seq）模型，以预测每小时和每天的精确预测，并对 VRF 系统的波动功耗进行快速反馈控制。优化后的 seq2seq 模型被集成到智能负载控制（ILC）中。ILC 可用于管理 VRF 系统，利用定量输入和定性规则对室内机组进行动态优先缩减。总之，研究结果表明，基于深度学习的控制可以协调三栋商业建筑中 VRF 系统的可控负载。作为控制算法的目标函数，具有深度学习功能的 ILC 可将耗电量控制在所需的目标水平内，还可将反映受控室内设备状态的室内温度控制在所需的目标水平内。

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引用次数: 0

Thermal environment and waste heat recovery of high-radiant heat workshop 高辐射供热车间的热环境和余热回收

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.jobe.2024.111014

The high temperature of the high radiant heat reservoir workshop, the poor working environment of workers, and the long-term heat stress will hinder the brain power and cardiac function, which is an important environmental factor that causes unsafe behavior, and the waste heat loss in the workshop is serious. Taking the heat reservoir power of 10 kW as the research object, the role of heat shield under different water flow conditions in the waste heat recovery and reduction of workshop temperature was analyzed. The results show that when the mass flow rate of cooling water is 0.7 kg/s, the average indoor temperature is 22.39 °C, the cooling range is 39.14 %, and the waste heat recovery efficiency is 84.4 %, and the heat recovery effect is obvious. At the same time, the fitting relationship between outlet water flow and water temperature is obtained. The research results can provide a reference for the improvement of the thermal environment and waste heat recovery and utilization of the actual high-radiation heat workshop.

高辐射蓄热车间温度高，工人工作环境差，长期热应激会阻碍脑力和心脏功能，是导致不安全行为的重要环境因素，车间余热损失严重。以蓄热器功率为 10 kW 为研究对象，分析了不同水流条件下隔热箱对余热回收和降低车间温度的作用。结果表明，当冷却水质量流量为 0.7 kg/s 时，室内平均温度为 22.39 ℃，降温幅度为 39.14 %，余热回收效率为 84.4 %，热回收效果明显。同时，得到了出水流量与水温的拟合关系。研究成果可为实际高辐射热力车间热环境的改善和余热回收利用提供参考。

引用次数: 0

Reusable timber modular buildings, material circularity and automation: The role of inter-locking connections 可重复使用的木制模块化建筑、材料循环性和自动化：互锁连接的作用

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-10 DOI: 10.1016/j.jobe.2024.110965

As sustainability becomes a central concern in construction, the industry witnesses a significant surge in the adoption of material circularity principles, reflecting a new approach to resource management. Although mass timber construction holds significant potential for end-of-life (EoL) material circularity due to its natural materials and prefabrication, conventional connection systems hinder material reuse. Integrating interlocking techniques into modular construction could enhance circularity and enable future autonomous construction. This paper summarises design-for-reuse (DfR) strategies focusing on connection design for rapid assembly and disassembly of Cross-Laminated Timber (CLT) modules. These strategies can promote innovative connections with enhanced material circularity, which were illustrated through a recently proposed conceptual interlocking connections (MOD-IT). Additionally, a comparative cradle-to-cradle Life Cycle Assessment (LCA) evaluates the environmental impact and circularity potential of timber modular buildings using this connection system. The study underscores the pivotal role of strategic connection design in achieving a closed-loop system in timber construction. This advancement fosters sustainability by improving efficiency, adaptability, reusability, and autonomy in the construction process.

随着可持续发展成为建筑业关注的核心问题，该行业采用材料循环利用原则的数量大幅增加，这反映了一种新的资源管理方法。虽然大规模木结构建筑因其天然材料和预制构件而在报废（EoL）材料循环利用方面具有巨大潜力，但传统的连接系统阻碍了材料的再利用。将联锁技术融入模块化建筑可提高循环性，实现未来的自主建筑。本文总结了以连接设计为重点的重复使用设计（DfR）策略，以实现交叉层压木材（CLT）模块的快速组装和拆卸。这些策略可促进创新连接，增强材料的循环性，并通过最近提出的概念性互锁连接（MOD-IT）加以说明。此外，一项 "从摇篮到摇篮 "生命周期评估（LCA）比较研究评估了使用这种连接系统的木材模块化建筑对环境的影响和循环潜力。这项研究强调了战略性连接设计在实现木材建筑闭环系统中的关键作用。这一进步通过提高建筑过程中的效率、适应性、可重复使用性和自主性，促进了可持续发展。

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引用次数: 0

Study on the structural behavior and reinforcement design of openings in subway station floor slabs 地铁站楼板开口的结构行为和加固设计研究

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.jobe.2024.110994

This paper investigates the structural behavior of openings in subway station floor slabs through model experiments and finite element simulation. The study analyzes the effects of the opening's aspect ratio, dimensions, and position on the stress characteristics of various structural components. Based on the stress levels and failure characteristics at different locations in the station structure, three reinforcement schemes are proposed: adding corner fillets, installing buttress columns, and adding ring beams. Comparative analysis with the original structure's internal forces and displacement patterns reveals the effectiveness of each reinforcement scheme. The results show that openings reduce the moment of inertia of the floor slab cross-section, weakening the slab's stiffness and making the area around the openings and slab-column joints prone to local damage. Increasing the aspect ratio of the opening, enlarging its dimensions, or closely arranging multiple openings diagonally reduces the local load-bearing capacity of the structure. Adding corner fillets can reduce the maximum equivalent stress in the slab by more than 15 %, alleviating stress concentration caused by the openings. Buttress columns and ring beams increase the stiffness of the side walls, distribute the lateral forces causing wall bending moments, and enhance the structure's resistance to lateral displacement.

本文通过模型试验和有限元模拟研究了地铁站楼板开口的结构行为。研究分析了开口的长宽比、尺寸和位置对各结构部件应力特性的影响。根据车站结构不同位置的应力水平和破坏特征，提出了三种加固方案：增加角片、安装支撑柱和增加圈梁。通过与原结构内力和位移模式的对比分析，可以看出每种加固方案的有效性。结果表明，开口降低了楼板横截面的惯性矩，削弱了楼板的刚度，使开口周围区域和板柱连接处容易发生局部破坏。增大开口的长宽比、扩大开口尺寸或将多个开口对角紧密排列，都会降低结构的局部承载能力。增加角部圆角可将板中的最大等效应力降低 15%以上，从而减轻开口造成的应力集中。支撑柱和圈梁可增加侧墙的刚度，分散造成墙体弯矩的侧向力，并增强结构的抗侧向位移能力。

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引用次数: 0

Stepwise modeling approach to explore the interfacial behavior of Ca(OH)2/Sulfate 分步建模法探索 Ca(OH)2/Sulfate 的界面行为

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.jobe.2024.111005

Concrete infrastructure within the salt spray zone is subject to corrosion triggered by sulfate, resulting in the deterioration of durability. Nevertheless, the atomic interface of Ca(OH)₂/sulfate remains incompletely understood. In the present study, the adsorption behavior (chemical or physical) of gas sulfate was firstly determined by density functional theory approach, followed by a deep investigation on physical adsorption mechanism of Ca(OH)₂/sulfate interface through classical molecular dynamics (MD) simulations, and presenting detailed conformations of sulfate hydration layer via quantum chemistry (QC) calculations. Results suggested: The chemical adsorption activity between sulfur gas and Ca(OH)₂ surface is negligible, with the primary role of SO₂/SO₃ being to act as a donor of sulfate ions in the corrosion process. Large-scale MD simulations reveal that the diffusion of sulfate ions to the CH surface requires the formation of a complete first hydration layer. Therefore, in high-concentration droplets, the competitive effect between sulfate ions and water molecules leads to agglomeration. The conformations of the three most probable types of hydrated layers of sulfate ions at room temperature were determined using the Boltzmann distribution calculated via QC methods, and corresponding strength of hydrogen bonding within these hydrated layers was evaluated.

盐雾区内的混凝土基础设施会受到硫酸盐引发的腐蚀，导致耐久性下降。然而，人们对 Ca（OH）2/硫酸盐的原子界面仍不甚了解。在本研究中，首先通过密度泛函理论方法确定了气体硫酸盐的吸附行为（化学或物理），然后通过经典分子动力学（MD）模拟深入研究了 Ca（OH）2/硫酸盐界面的物理吸附机理，并通过量子化学（QC）计算展示了硫酸盐水合层的详细构象。结果表明硫气体与 Ca(OH)₂ 表面之间的化学吸附活性可以忽略不计，SO2/SO3 在腐蚀过程中的主要作用是充当硫酸根离子的供体。大规模 MD 模拟显示，硫酸根离子扩散到 CH 表面需要形成完整的第一水化层。因此，在高浓度液滴中，硫酸根离子和水分子之间的竞争效应会导致团聚。利用 QC 方法计算的玻尔兹曼分布确定了室温下硫酸根离子水合层三种最可能类型的构象，并评估了这些水合层内相应的氢键强度。

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引用次数: 0

A joint optimization strategy for electric vehicles and air conditioning systems with building battery configuration 电动汽车和空调系统与建筑电池配置的联合优化策略

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.jobe.2024.110984

Building air conditioning systems, electric vehicles and battery energy storage systems all provide substantial flexibility for grid operations. However, the joint optimization strategy involving these three demand response resources in buildings has been infrequently studied. This research proposes a day-ahead optimization strategy to coordinate the joint operation of air conditioning systems and electric vehicles. In this framework, cooling load is predicted using an autoregressive exogenous model, while electric vehicle charging load is predicted through Monte Carlo simulations. An evaluation method is introduced to assess the comprehensive benefits of the demand response strategy, considering thermal comfort, economic efficiency, and grid friendliness. Using an office building in Tianjin, China, as a case study, the results indicate that the joint optimization strategy reduces operational costs by 3.71 % and peak electricity load by 38.62 % compared to the original strategy. Furthermore, it enhances the grid friendliness of the energy system by 42.64 %. The configuration of the battery energy storage system is also explored in conjunction with the optimization strategy to further improve grid friendliness. The impact of economic factors and thermal comfort on the configuration of the battery energy storage system is discussed. In the case study, raising the upper temperature limit by 1 °C can save at least 17.1 % in capacity, while battery energy storage system investment and operational costs can respectively be reduced by 55.04 % and 27.14 % within the thermal comfort range.

建筑空调系统、电动汽车和电池储能系统都为电网运行提供了极大的灵活性。然而，涉及建筑物中这三种需求响应资源的联合优化策略却鲜有研究。本研究提出了一种协调空调系统和电动汽车联合运行的日前优化策略。在此框架中，制冷负荷使用自回归外生模型进行预测，而电动汽车充电负荷则通过蒙特卡罗模拟进行预测。在考虑热舒适度、经济效益和电网友好性的同时，还引入了一种评估方法来评估需求响应策略的综合效益。以中国天津的一栋办公楼为例，研究结果表明，与原始策略相比，联合优化策略降低了 3.71% 的运营成本和 38.62% 的峰值电力负荷。此外，它还将能源系统的电网友好性提高了 42.64%。此外，还结合优化策略探讨了电池储能系统的配置，以进一步提高电网友好性。讨论了经济因素和热舒适度对电池储能系统配置的影响。在案例研究中，将温度上限提高 1 °C，可节省至少 17.1 % 的容量，而在热舒适度范围内，电池储能系统的投资和运营成本可分别降低 55.04 % 和 27.14 %。

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引用次数: 0

A closed-loop recycling of wastewater derived from aqueous carbonation of basic oxygen furnace slag in cement paste production 水泥浆生产中碱式氧炉炉渣水碳化废水的闭环循环利用

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.jobe.2024.111004

Aqueous carbonation (AC) treatment is a promising method for enhancing the cementitious activity of Ca- and Mg-rich solid wastes, such as basic oxygen furnace slag (BOFS), while also reducing carbon emissions. However, the carbonated filtrate (CF) solution generated during the AC process poses significant environmental challenges and limits its large-scale application. This paper, therefore, explores the feasibility of recycling CF in cement paste production as a strategy for managing AC wastewater. The study examines the impact of CF on the physico-mechanical properties, hydration behavior and microstructure of cement pastes (pure and blended with either 10% as-received or carbonated BOFS), compared to those prepared with tap water (TW) and carbonated water (CW). The results indicate that carbonated solutions (CF and CW) promote the hydration of aluminate phase in cement, with a more pronounced effect observed for CW. The solid suspensions in CF, particularly nesquehonite, restrict the growth space for calcium silicate hydrates (C-S-H) in the paste matrix, resulting in the formation of foil-like Type II C-S-H and lowering compressive strength. However, the additional nucleation sites provided by calcite crystals in carbonated BOFS (C-BOFS) accelerate cement hydration in CF-based pastes and mitigate strength loss by promoting the formation of more fibrillary C-S-H. Furthermore, the addition of a superplasticizer reduces interparticle forces in the C-BOFS-CF paste, further enhancing strength development and achieving a 28-day strength comparable to that of the control sample (OPC-TW paste).

水碳化（AC）处理是一种很有前景的方法，可提高富含钙和镁的固体废物（如碱性氧气炉渣（BOFS））的胶凝活性，同时减少碳排放。然而，在 AC 处理过程中产生的碳化滤液（CF）对环境造成了巨大挑战，限制了其大规模应用。因此，本文探讨了在水泥浆生产过程中回收利用碳化滤液作为管理 AC 废水的一种策略的可行性。与使用自来水 (TW) 和碳酸水 (CW) 制备的水泥浆相比，本研究考察了碳酸钙对水泥浆（纯水泥浆和掺入 10% 原水或碳酸化 BOFS 的水泥浆）的物理机械性能、水化行为和微观结构的影响。结果表明，碳酸化溶液（CF 和 CW）可促进水泥中铝酸盐相的水化，CW 的效果更为明显。CF 中的固体悬浮物，尤其是内沸石，限制了浆体基质中硅酸钙水合物（C-S-H）的生长空间，导致形成箔状 II 型 C-S-H，降低了抗压强度。然而，碳化 BOFS（C-BOFS）中的方解石晶体提供了额外的成核位点，可加速 CF 型浆料中的水泥水化，并通过促进形成更多纤维状 C-S-H 来减轻强度损失。此外，添加超塑化剂可降低 C-BOFS-CF 浆料中的颗粒间作用力，进一步增强强度发展，使 28 天强度与对照样本（OPC-TW 浆料）相当。

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引用次数: 0

Investigation on typhoon-induced aero-elastic response of membrane structures by wind tunnel test and numerical simulation 通过风洞试验和数值模拟研究台风引起的膜结构气动弹性响应

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.jobe.2024.110996

Extreme winds, such as typhoons, can lead to serious vibration and damage for flexible membrane roofs. An understanding of the aeroelastic behavior experienced by membrane structures during typhoons is therefore significant to allow well designed in practice. This paper investigates the aeroelastic response of umbrella shaped membrane structures under typhoon experimentally and numerically. The flexible scaled model is tested in typhoon field simulated in wind tunnel to investigate the aeroelastic characteristics varying with wind velocities and wind directions, including displacement response, non-Gaussian characteristics, frequency, modal shape and damping ratios et al. The full coupled fluid-structure interaction numerical model proposed is benchmarked and expanded in parameter discussions. The results indicate that non-Gaussian characteristics appear significant with positive skewness in pressure region and negative skewness in suction region. The probabilistic distribution proves leptokurtic type with kurtosis beyond three. The displacement response in statistics increases almost linearly with wind velocity while the non-Gaussian characteristics remain robust. The high-order mode shapes can be excited in typhoon, and their frequencies and damping ratios vary with wind velocities. The effects of both wind velocity and membrane pretension are proved to be more remarkable than rise-span ratio. This study can address the deficiency of current studies and provisions on the dynamic response of membrane structures in typhoons.

台风等极端风力会导致柔性膜结构屋顶发生严重振动和损坏。因此，了解膜结构在台风期间的气动弹性行为对于在实践中进行良好设计具有重要意义。本文通过实验和数值方法研究了台风下伞形膜结构的气弹响应。在风洞模拟的台风场中测试了柔性缩放模型，研究了随风速和风向变化的气动弹性特性，包括位移响应、非高斯特性、频率、模态形状和阻尼比等。结果表明，非高斯特性非常明显，压力区域为正偏斜，吸力区域为负偏斜。概率分布证明了峰度超过 3 的畸变类型。统计中的位移响应几乎随风速呈线性增长，而非高斯特征则保持稳定。高阶模态振型在台风中会被激发，其频率和阻尼比随风速而变化。事实证明，风速和膜预张力的影响比升跨比更为显著。这项研究弥补了目前关于台风中膜结构动态响应的研究和规定的不足。

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引用次数: 0

Reducing the cost of home energy upgrades in the US: An industry survey 降低美国家庭能源升级的成本：行业调查

IF 6.7 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Journal of building engineering

Pub Date : 2024-10-09 DOI: 10.1016/j.jobe.2024.110939

Decarbonizing the US residential building stock requires a substantial acceleration in home energy upgrades. Numerous barriers exist to accelerating adoption of efficient and electric building technologies, but foremost among these is high upfront costs. This study uses an industry survey delivered to a sample of home energy professionals to examine promising cost reduction strategies across a range of project types, including HVAC, water heating, and envelope/insulation projects. The survey included quantitative and qualitative questions to collect evidence on the estimated cost reduction potential of these strategies and their likelihood of use in the construction industry. The 167 survey respondents included contractors, energy consultants, architects, manufacturers, and others with experience in delivering energy upgrades in single-family and multifamily buildings in the US. Results show that significant cost reductions are achievable by minimizing additional infrastructure costs (such as replacing electric panels), streamlining project planning/management, and deploying innovations that simplify installation. We find that for a typical deep retrofit project, including heat pumps for space and water heating in addition to envelope upgrades, the strategies could result in a total installed cost reduction of nearly 50 %, dramatically improving the customer economics of such a project. This research makes a novel contribution to the literature on strategies to reduce the costs of residential retrofits. We discuss how our study's insights on the highest-value cost reduction strategies for home energy upgrades can further accelerate their uptake in the US housing stock.

美国住宅建筑的去碳化需要大幅加快家庭能源升级。在加速采用高效和电动建筑技术方面存在许多障碍，但其中最主要的是高昂的前期成本。本研究通过对家庭能源专业人员进行抽样行业调查，对暖通空调、水加热和围护结构/保温项目等一系列项目类型中有望降低成本的策略进行研究。调查包括定量和定性问题，以收集有关这些策略的估计成本降低潜力及其在建筑行业使用可能性的证据。167 位调查对象包括承包商、能源顾问、建筑师、制造商以及其他在美国单户和多户建筑能源升级方面具有丰富经验的人员。结果表明，通过最大限度地减少额外的基础设施成本（如更换电板）、简化项目规划/管理以及采用简化安装的创新技术，可以大幅降低成本。我们发现，对于一个典型的深度改造项目，除围护结构升级外，还包括用于空间和水加热的热泵，这些策略可使总安装成本降低近 50%，从而显著提高此类项目的客户经济效益。这项研究为有关降低住宅改造成本策略的文献做出了新的贡献。我们将讨论我们的研究对降低住宅能源升级成本的最高价值策略的见解如何进一步加快其在美国住宅中的普及。

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引用次数: 0