IN—SITU MEASUREMENTS OF RADON EXHALATION RATE FROM BUILDING SURFACE IN HONG KONG

EPA-standardized activated charcoal canisters were used to collect radon exhaled from building surfaces and analyzed using γ-spectroscopy to obtain the radon exhalation rates. More than 120 samples were analyzed in more than 10 buildings situated in different areas of Hong Kong. Variations were identified in the exhalation rates at different levels in a building, for different covering materials and for the presence of cracks in walls. The radon exhalation rate from the most common concrete walls and covering materials was found to be approximately 13 mBq·m-2·s-1. This may be the cause of a relatively high indoor radon concentration in Hong Kong.

Comparative Analysis of Building Rating Systems and Occupant Rating Systems

To begin with, rating systems are a beneficial tool in determining the efficiency of a building’s ability to utilise its resources effectively. In this study, the two elements under comparison are the Building Rating Systems (BRSs) and Occupant Rating Systems (ORSs). The main objective of this paper is to be able to examine the most commonly applied international and national BRS and ORS and, based on that, discover the possibility of developing an integration of both the BRS and ORS into one rating system. Quite simply, a BRS is a method by which buildings are assessed and given a score based on numerous features such as the efficiency of each of the services, total energy consumption, and alternate options of consumption. There are various BRSs that are implemented globally, each with its own set of criteria and specifications. Thus, based on the analysis of the benefits and drawbacks of both types of rating systems, it could be deduced that a well-rounded rating system with all technical and non-technical aspects combined would be beneficial to both the efficiency of the building as well as the building occupants’ health and well-being.

DHW Design Flow Rates and Consumption Profiles in Educational, Office Buildings and Shopping Centres

The paper gives a thorough survey of the studies of different authors in the field of domestic hot water (DHW) consumption and consumption profiles. It presents an overview of the research done into DHW by the Tallinn University of Technology. Working out on the basis of investigations has been new empirical formulas for determining design flow rates for schools, kindergartens, office buildings and shopping centres. DHW consumption profiles of typical buildings are presented. Comparisons are given on the determination of DHW design flow rates by the standard EVS 835, the EN 806-3 and the recommended formulas. The latter makes it possible to considerably decrease the design flow rates which in turn enables to deminish the load of the equipment, to improve the quality of control and to decrease the diameters of the pipes of the district heating network and the losses of heat in them.

Assessment on Energy Self-Sufficiency Rate for Building Integrated Photovoltaics and Fuel Cell System in Japan

A building integrated photovoltaic (PV) and fuel cell (FC) system is proposed for assessment of the energy self-sufficiency rate in a city in Japan. The electricity consumed in the building is mainly supplied by solar panels, while the gap between the energy demand and supply is solved by the FC that is powered by the H2 produced by water electrolysis with surplus power of PV. A desktop case study of using the proposed system in Tsu city which is located in central part of Japan, has been conducted. The results found that the self-sufficiency rates of PV system to electricity demand of households (RPV) during the daytime in April and July are higher than those in January and October. The results also reveal that the self-sufficiency rate of FC system to the electricity demand (RFC) is 15% - 38% for the day when the mean amount of horizontal solar radiation is obtained in January, April, July and October. In addition, it is found the optimum tilt angle of solar panel installed on the roof of the buildings should be 0 degree, i.e., placed horizontally.

Energy Assessment of Building Integrated Photovoltaics and Fuel Cell Systems: Design Study for Building(s) of Mie, Japan

A building integrated energy system (photovoltaic (PV) and fuel cell (FC)) is proposed for assessment of the energy self-sufficiency rate in five cities of Mie prefecture in Japan. In this work, it is considered that the electricity requirement of the building is provided by the building integrated photovoltaic (BIPV) system and the gap between the energy demand and BIPV supply is fulfilled by the FC. The FC is powered by the electrolytic H2 produced from the surplus power of PV. A design study of using the proposed system in five cities in Mie prefecture, which are in center part of Japan, has been performed. It has been observed that the monthly power production from BIPV is higher in spring and summer, while it is lower in autumn and winter at all considered locations. The self-sufficiency rate of the FC system is higher with decreasing households’ number and it has been observed that the 12 households are more suitable for full cover of the electricity demand by the combined system of PV and FC. The relationship between the households’ number and self-sufficiency rate of the FC system per solar PV installation area can be expressed by exponential curve. The coefficient of the exponential curve can predict the suitable city for the BIPV system with FC system utilizing electrolytic H2 generated by using excess energy from the PV system.

地铁线路邻近建筑物室内振动烦恼率预测分析

为实现地铁线路邻近建筑物室内振动舒适度定量计算,提出场地振动响应数值模拟与链式衰减公式相结合的预测的方法,得到不同类型建筑物室内振动响应。首先,以预测振级为自变量,采用正态分布函数描述人对振动感觉的随机性,建立地铁线路邻近建筑物室内振动烦恼率模型;其次,以石家庄地铁为例,建立了场地振动预测模型,借助链式衰减公式,得到不同类型建筑物的室内振动烦恼率分布规律。研究结果表明:建立的烦恼率模型变异系数取0.15时,均方根误差为0.086,模型预测精度满足要求;在设计工况下给出了各类建筑物在不同区域的达标距离,对于0类区域,Ⅰ~Ⅴ类建筑物达标距离分别为12,14,20,44和46 m,对于5类区域任意距离都达标。该研究成果可为烦恼率评价法在地铁沿线建筑物振动舒适度预测和评估应用提供参考。

预制装配率对装配式建筑工程造价的影响分析

针对装配式建筑相较于传统现浇式建筑工程造价增加问题,依据相关计算规则,在满足规范预制装配率的前提下,对不同类型装配式建筑、不同预制装配率的混凝土小高层住宅及不同预制构件类型的工程造价进行对比分析,探讨预制装配式建筑与传统现浇式建筑间的成本差异,并从经济角度出发,对预制构件、部品及技术的优先选择进行排序,以期为优化PC深化设计,探究投资最少、成本最低的预制装配率方案提供参考。

火灾后建筑物的结构安全性检测鉴定与分析

以某住宅楼火灾后的结构安全性检测鉴定为例,提出一种火灾后建筑物主体结构安全性检测鉴定思路与方法,对类似的工程结构安全性鉴定分析具有一定借鉴意义。

树木墙冠距对独立式农宅节能率的影响研究

树木对建筑具有节能效应,但树木与农宅的空间关系对农宅能耗的影响规律尚需进一步挖掘。为充分发挥树木降温节能的生态效益,以浙江嘉兴独立式农宅为对象,应用数值模拟法获取90种不同空间位置关系所对应的农宅节能率,最后分析不同农宅朝向、不同树木方位与不同墙冠距对农宅节能率的综合影响规律。结果表明,以不同墙冠距对应的节能率变化范围为依据,当农宅为正南朝向时,可得出树木方位对应的节能率大小依次为:西侧≈东侧>东南侧≈西南侧>东北侧≈西北侧。对位于农宅东、西两侧的树木而言,可得出农宅朝向对应的节能率大小依次为:正南≈南偏西10°>南偏东20°>南偏东10°>南偏西20°。上述研究可为节能视角下的独立式农宅邻近绿化提供科学依据。

装配式建筑评价标准研究

研究以西安市某装配式建筑项目为例,应用各省市评价标准进行了装配率测算,并对计算结果进行了对比分析。根据长期工程实践,剖析了各省市装配式建筑评价标准当前存在的主要问题,并针对性地提出了评价标准发展建议,指出科学合理的评价体系和评价方法是装配式建筑产业健康可持续发展的关键。

基于绿色建筑评价体系的建筑工程管理措施探析

随着城镇化的不断发展,工程建设能耗问题带来的环境影响日益严重,而目前的绿色建筑工程管理还面临着诸多问题和不足。因此,在加强建筑工程全生命周期管理的过程中,结合精细化管理模式,贯彻落实绿色建筑理念,不断完善和提升绿色建筑工程管理水平是当务之急。梳理了国内外绿色建筑评价体系,并对比分析其异同点,结合我国绿色建筑评价体系在建筑工程管理中的应用实践,从决策、设计、施工、运营4个阶段,提出基于绿色建筑评价体系的建筑工程管理提升措施。旨在构建与绿色建筑评价相适应的建筑工程管理体系,进一步提升建筑工程管理水平。

基于延时微分的旋转导向工具造斜率预测方法研究

【目的】旋转导向工具造斜率的准确预测是实现工具精准控制的前提,为掌握旋转导向底部钻具组合造斜率变化规律。【方法】根据工具结构特点,采用欧拉-伯努利梁方程法对复合式旋转导向工具底部钻具组合进行受力分析。通过结合底部钻具几何关系,得到各节工具转角与钻头预钻进偏角计算方法,并将旋转导向工具各节点与钻头间距离作为空间延时周期,最终建立基于延时微分的旋转导向底部钻具组合的造斜率预测模型。该模型综合考虑了工具本身几何尺寸与结构、与地层有关的钻头切削各向异性、钻压以及工具材料及内外径有关的抗弯刚度等参数对造斜率的定量影响。【结果和结论】研究表明:(1)该模型预测结果与斯伦贝谢成熟应用的基于有限元分析的钻具造斜率预测软件仿真结果具有良好的吻合度,预测结果差值均保持在0.5(°)/30 m以内,符合工程要求。(2)同时该方法还可在钻具姿态测量短节的实际测量数据基础上补偿钻头与测量单元间距带来的测量误差问题,为解决测量盲区提供一种新的途径。基于空间延时微分的造斜率预测方法为旋转导向系统底部钻具组合的结构优化及钻井参数优选提供理论依据和快速分析手段。建立的模型易于仿真和移植,在实际工程应用中可获取较好的实时响应,为基于数字孪生的旋转导向工具研发提供准确的钻具运动模型基础。

大连养老建筑供暖季室内环境与老年人心率关联性

为了解养老建筑室内环境与老年人心率之间的关联性,对大连城市和农村地区的26名住户在供暖季展开了调研及入户实测,对其室内环境参数及心率健康情况进行了72 h的连续监测,并采取问卷调查的方式获得受试老年人对室内环境的主观评价。研究结果表明:被调查的城市住宅室内热环境均表现良好,城市住宅的室内温度高于农村且温湿度的波动均小于农村;农村和城市的实测房间室内CO_(2)浓度均较高,农村室内的PM2.5污染严重,比城市室内平均浓度高出302%;实测房间无严重噪声污染,存在部分时间段噪声值超标情况,城市住宅的老年人对声环境营造有着更高的要求;老年人动态心率与温度、PM2.5浓度、噪声呈正相关关系。

基于《危险房屋鉴定标准》的某砌体房屋危险性鉴定

以某砌体房屋为例,探讨现行JGJ 125—2016《危险房屋鉴定标准》在实际鉴定工作中的应用。通过对房屋结构、材料、裂缝等多方面的调查和分析,确定房屋的危险性。结合JGJ 125—2016《危险房屋鉴定标准》中的相关规定,采用综合比例法,并通过建模计算。根据分析结果,其房屋危险性等级综合评定为C级,构成局部危房。对房屋的危险性进行客观、全面的评估,并提出处理建议,为类似砌体房屋的危险性鉴定提供参考和借鉴。

6/10 kV配电线路防雷分析及应用

针对河南油田6/10 kV配电线路雷击跳闸情况,进行雷击过电压分析,得出雷击跳闸的主要原因为建弧率过高。由6/10 kV配电线路不同绝缘子配置方案下的雷击过电压的仿真计算结果可知,采用“一针两棒”绝缘子优化方案可使建弧率大幅降低,方案效果显著。

北京市某公共建筑综合节能改造与能效评估

以北京市东城区某综合园区为例,根据园区现状对其围护结构热工性能、供暖空调、建筑照明及用水器具进行节能诊断及能耗分析。结果显示:建筑供暖耗热量及照明耗电量占比分别为58.96%和10.24%,为挖掘改造潜力并确定基准能耗提供了依据;通过围护结构保温层加装、门窗更换、高效空调设备更换、照明灯具更换及节水器具更换等节能技改措施进行综合节能改造,计算改造后能耗;将不同能源类型能耗归一化为标煤,经测算,改造后项目节能量约为71.0 tce,综合节能率35.52%,减少向大气排放二氧化碳175.38 t,节能减排效果显著,为类似地区公建节能改造提供了借鉴和参考。本次能评估多采用理论模拟计算方法,还需改造后实际运行数据对比支撑。

差异纹理条件下木材燃烧性能研究

为探究不同纹理木材火焰燃烧特性,选择了5种常见木材,搭建试验装置,设计15组试验,从质量损失速率、最大火焰高度、燃烧时间等方面,分析了横向、竖向、斜向纹理木材的燃烧特性。结果显示:木材的质量损失速率与纹理有关,纹理对松木燃烧时的最大火焰高度影响最小,对杉木影响最大;榉木燃烧持续时间比其他4种木材长,杉木燃烧持续时间相对较短。研究结果有助于更好地掌握纹理对木材燃烧火焰特性的影响,为木结构建筑选材及火灾防治提供理论支撑。

基于BIM技术的装配式建筑建造全过程碳排放及经济性分析

建筑业资源消耗量大,对环境影响深刻,故其减排意义重大。本文利用建筑信息模型(BIM)对装配式建筑建造全过程碳排放及经济性进行研究。在考虑碳排放成本基础上,分析装配式建筑预制构件的预制率与综合成本之间的关系,调制构件之间的比例,得到不同预制率下的装配式建筑结构综合成本变化趋势,以期为降低装配式建筑成本提供参考。

浆纱车速与压浆力对上浆率的影响关系

现代浆纱机配备了浆纱车速-压浆力匹配调控技术,以稳定控制上浆率;目前普遍采用车速-压浆力线性调节方案,但缺乏一定的理论指导,往往会造成上浆率稳定性控制的效果不理想。为提高上浆率控制稳定性,对车速与压浆力对上浆率的影响关系进行研究。通过对浆纱过程中浆液的浸透与压出进行合理化假设,构建了车速、压浆力和上浆率的关系模型。基于该模型,提出不同车速下压浆力的求解方法,用于实现上浆率的稳定控制。该模型在浆纱实验数据中的拟合优度R^(2)达0.8754,较线性模型高0.1388,验证了模型构建的合理性。依据该模型构建上浆率稳定控制方法,在不同车速下对压浆力进行调控实验,实测上浆率与设定值的平均相对误差为2.59%,有效实现了不同车速下的上浆率稳定控制。构建的车速、压浆力、上浆率关系模型,对解释车速与压浆力影响上浆率的机理具有一定的理论意义;基于该模型构建的上浆率稳定控制方法,为提高浆纱上浆率稳定控制水平提供了新的途径。

基于绿色建筑的污水再利用研究

绿色建筑是实现可持续发展的关键,注重资源的有效利用和环境保护。在此理念下,污水再利用成为重要措施,旨在节水、循环利用和减少能源消耗。文章首先概述了全球绿色建筑评级体系,重点分析了LEED、BREEAM和CASBEE等标准对污水再利用的规定。随后详细分析了污水再利用与生命周期评估的关系,突出了生命周期评估在评估再利用系统可持续性方面的重要性。进一步探讨了污水再利用与绿色建筑的紧密关系,包括节水、循环利用和降低能源消耗等方面。最后,总结了设计污水再利用系统时需要考虑的关键因素,如系统选择、水质要求和处理工艺等,以促进建筑行业向更环保、可持续的方向迈进,并提供理论和实践指导。