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Effect of Straw Mixing Amount on Mechanical Properties of Admixture-adding Hollow Block
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作者 刘军 ZHOU Honghong OUYANG Peng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第3期508-513,共6页
The bonding mechanism between straw and concrete was analyzed through testing the compressive strength and flexural strength of hollow block, with different straw amount and different dosage and types of admixtures. T... The bonding mechanism between straw and concrete was analyzed through testing the compressive strength and flexural strength of hollow block, with different straw amount and different dosage and types of admixtures. The test results show that the mechanical properties of hollow blocks reduced after adding straws, and the more straws was added, the more hollow block density decreased. But adding A12(SO4)3 and CaC12 could improve the dense degree between rice straw and concrete. And when the proportion of straw mixing amount was 10%, the flexural strength of the early strength agent (2% A12(SO4)3, CaC12) added hollow block reached as maximal as 3.1 MPa, while the compressive strength was 9.1 MPa, consisting with the strength grade of common concrete hollow block MU7.5. 展开更多
关键词 straws ADMIXTURES mixing amount hollow block
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Dual responsive block copolymer coated hollow mesoporous silica nanoparticles for glucose-mediated transcutaneous drug delivery
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作者 Yaping Wang Songyue Cheng +4 位作者 Wendi Fan Yikun Jiang Jie Yang Zaizai Tong Guohua Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第11期35-42,共8页
A self-regulated anti-diabetic drug release device mimicking pancreatic cells is highly desirable for the therapy of diabetes. Herein, a glucose-mediated dual-responsive drug delivery system, which combines pH-and H_(... A self-regulated anti-diabetic drug release device mimicking pancreatic cells is highly desirable for the therapy of diabetes. Herein, a glucose-mediated dual-responsive drug delivery system, which combines pH-and H_(2)O_(2)-responsive block copolymer grafted hollow mesoporous silica nanoparticles(HMSNs)with microneedle(MN) array patch, has been developed to achieve self-regulated administration.The poly[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl acrylate]-b-poly[2-(dimethylamino)ethyl methacrylate](PPBEM-b-PDM) polymer serves as gate keeper to prevent drug release from the cavity of HMSNs at normoglycemic level. In contrast, the drug release rate is significantly enhanced upon H_(2)O_(2)and pH stimuli due to the chemical change of H_(2)O_(2)sensitive PPBEM block and acid responsive PDM block. Therefore, incorporation of anti-diabetic drug and glucose oxidase(GOx, which can oxidize glucose to gluconic acid and in-situ produce H_(2)O_(2)) into stimulus polymer coated HMSNs results in a glucose-mediated MN device after depositing the drug-loaded nanoparticles into MN array patch. Both in vitro and in vivo results show this MN device presents a glucose mediated self-regulated drug release characteristic, which possesses a rapid drug release at hyperglycemic level but retarded drug release at normoglycemic level. The result indicates that the fabricated smart drug delivery system is a good candidate for the therapy of diabetes. 展开更多
关键词 Diabetes Transcutaneous microneedles Stimuli-responsive drug release hollow mesoporous silica nanoparticles block copolymer
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Effect of Hole Configuration on Heat Transfer through a Hollow Block Subjected to Solar Flux
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作者 Mourad Najjaoui Thami Ait-Taleb +2 位作者 Abdelhalim Abdelbaki Zaki Zrikem Hassan Chaib 《Fluid Dynamics & Materials Processing》 EI 2022年第5期1339-1348,共10页
In this paper,some effort is provided to optimize the geometry of a concrete hollow brick(used in the construction of building roofs)in order to increase the related thermal resistance,thereby reducing energy consumpt... In this paper,some effort is provided to optimize the geometry of a concrete hollow brick(used in the construction of building roofs)in order to increase the related thermal resistance,thereby reducing energy consumption.The analysis is conducted for three different configurations of the hollow concrete bricks.Coupling of conduction,natural convection and thermal radiation phenomena is considered.Moreover,the flows are assumed to be laminar and two-dimensional for the whole range of parameters examined.The conservation equations are solved by a finite difference method based on the control volumes approach and the SIMPLE algorithm for velocity-pressure coupling.The results show that the aspect ratio affects neither the nature of the fluid flow nor the number of convective cells.However,the extension of the circulation cells increases with this parameter.Moreover,the cavities with a large aspect ratio lead to significant reductions in the heat transfer through the hollow block,these reductions reaching approximately 14%. 展开更多
关键词 Heat transfers coupled hollow block solar flux aspect ratio control volumes
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Coupled Conductive-Convective-Radiative Heat Transfer in Hollow Blocks with Two Air Cells in the Vertical Direction Subjected to an Incident Solar Flux
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作者 Mourad Najjaoui Thami Ait-taleb +2 位作者 Abdelhalim Abdelbaki Zaki Zrikem Hassan Chaib 《Fluid Dynamics & Materials Processing》 EI 2022年第5期1399-1407,共9页
This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and radiation.Blocks with two air cells deep ... This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and radiation.Blocks with two air cells deep in the vertical direction and three identical cavities in the horizontal direction are considered(typically used for building ceilings).Moreover,their outside horizontal surface is subjected to an incident solar flux and outdoor environment temperature while the inside surface is exposed to typical indoor environment conditions.The flows are considered laminar and two-dimensional over the whole range of parameters examined.The conservation equations are solved by means of a finite difference method based on the control volumes approach,relying on the SIMPLE algorithm for what concerns the coupling of pressure and velocity.The effects of the number of cells in the horizontal direction and the thermal conductivity on the heat transfer through the alveolar structure have been investigated.The results show that the number of holes has a significant impact on the value of the overall heat flux through the considered structure. 展开更多
关键词 Numerical simulation heat transfer coupled hollow concrete block control volumes approach
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Portland Cement-Residues-Polymers Composites and Its Application to the Hollow Blocks Manufacturing
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作者 Augusto Cesare Stancato Antonio Ludovico Beraldo 《Open Journal of Composite Materials》 2013年第1期1-6,共6页
Agricultural wastes and sawdust combined with cement matrix in the manufacture of building elements has been practiced with success in developed countries. In this study, sawdust from wood species (Pinus caribaea and ... Agricultural wastes and sawdust combined with cement matrix in the manufacture of building elements has been practiced with success in developed countries. In this study, sawdust from wood species (Pinus caribaea and Eucalyptus grandis) and an agricultural waste—rice husk (Oriza sativa) were combined with Portland cement type V (high initial strength), modified by polymer styrene-butadiene (SBR) addition. Hollow blocks produced with Eucalyptus grandis and rice husk residues showed better compressive strength;however, those produced with residues derived from Pinus caribaea presented non-satisfactory results, due to the particle size that was used. 展开更多
关键词 COMPOSITES Cement RESIDUES hollow blockS Ultrasonic Pulse Velocity (UPV)
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Analysis of Heat Transfer Phenomena inside Concrete Hollow Blocks
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作者 Joelle Al Fakhoury Emilio Sassine +3 位作者 Yassine Cherif Joseph Dgheim Emmanuel Antczak Thierry Chartier 《Journal of Building Material Science》 2022年第1期21-33,共13页
During both hot and cold seasons,masonry walls play an important role in the thermal performance between the interior and the exterior of occupied spaces.It is thus essential to analyze the thermal behavior at the hol... During both hot and cold seasons,masonry walls play an important role in the thermal performance between the interior and the exterior of occupied spaces.It is thus essential to analyze the thermal behavior at the hollow block’s level in order to better understand the temperature and heat flux distribution in its structure and potentially limit as much as possible the heat transfer through the block.In this scope,this paper offers an experimental and numerical in-depth analysis of heat transfer phenomena inside a hollow block using a dedicated experimental setup including a well-insulated reference box and several thermocouples and fluxmeters distributed at the boundaries and inside the hollow block.The block was then numerically 3D modelled and simulated using COMSOL Multiphysics under the same conditions,properties,and dimensions as the experimentally tested block.The comparison between the numerical and experimental results provides very satisfactory results with relative difference of less than 4%for the computed thermal resistance. 展开更多
关键词 hollow block CAVITIES Thermophysical properties Dynamic boundary conditions 3D modelling
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熔纺-选择性溶胀制备嵌段共聚物多通道中空纤维膜 被引量:1
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作者 钟丁磊 黄铎 +2 位作者 应翔 邱守添 汪勇 《化工进展》 EI CAS CSCD 北大核心 2024年第1期269-278,共10页
嵌段共聚物的熔纺-选择性溶胀是一种制备中空纤维膜的清洁生产工艺。本文提出构建多通道构型来提升嵌段共聚物中空纤维膜的性能,通过熔纺-拉伸-选择性溶胀,制备了具有3通道和7通道的聚砜/聚乙二醇嵌段共聚物中空纤维膜,研究了通道数、... 嵌段共聚物的熔纺-选择性溶胀是一种制备中空纤维膜的清洁生产工艺。本文提出构建多通道构型来提升嵌段共聚物中空纤维膜的性能,通过熔纺-拉伸-选择性溶胀,制备了具有3通道和7通道的聚砜/聚乙二醇嵌段共聚物中空纤维膜,研究了通道数、溶胀条件和拉伸行为对中空纤维膜微观结构、渗透性、截留率和耐压性的影响。由于壁厚的相互支撑作用,多通道中空纤维膜的渗透性和耐压性能都比单通道中空纤维膜有所提高,且可通过拉伸和溶胀条件实现膜性能在较大范围内的高效调控。在适当的通道数和拉伸比下,拉伸后的三通道中空纤维膜的通量比单通道中空纤维膜高20倍。此工作对使用清洁方法制备高性能的中空纤维膜具有重要意义。 展开更多
关键词 超滤 中空纤维膜 嵌段共聚物 多通道 选择性溶胀
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灌孔配筋混凝土模壳砌块基础竖向承载性能试验研究与分析
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作者 尹烁 慈梦尧 +3 位作者 王少杰 王旭 刘佩玺 郑宝磊 《混凝土》 CAS 北大核心 2024年第5期155-159,165,共6页
灌孔配筋混凝土模壳砌块基础具有免支模、整体性好、易施工等优点,为了研究其竖向承载性能和失效破坏模式,通过试验和数值分析研究了配筋方式、试件高度、侧向土压力等因素的影响。结果表明:模壳砌块参与灌孔配筋混凝土模壳砌块基础受力... 灌孔配筋混凝土模壳砌块基础具有免支模、整体性好、易施工等优点,为了研究其竖向承载性能和失效破坏模式,通过试验和数值分析研究了配筋方式、试件高度、侧向土压力等因素的影响。结果表明:模壳砌块参与灌孔配筋混凝土模壳砌块基础受力,其在失效破坏时外围剥落、内部横肋可被灌孔混凝土有效约束;内置箍筋能显著提高试件开裂荷载并改善变形性能,但对竖向极限承载力无显著影响,失效时箍筋呈受压屈曲灯笼状外鼓;试件高度增加即高厚比增加,竖向极限承载力小幅下降(最大降幅5.35%);侧向土压力对无箍筋试验组的竖向承载性能无显著影响,但其与内置箍筋会形成双重约束作用并显著改善内置箍筋基础的竖向承载性能。GB/T 50003—2011《砌体结构设计规范》适用于灌孔配筋混凝土模壳砌块基础竖向极限承载力的计算,建立的有限元模型分析结果可靠,可为工程应用或同类研究提供参考。 展开更多
关键词 灌孔配筋砌块砌体 模壳砌块 配筋砌体 条形基础 双重约束
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相变蓄能空心砌块体系热性能测试与构造分析
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作者 张源 杨宇涵 +1 位作者 许立 李胜才 《建筑技术》 2024年第13期1647-1654,共8页
本研究建立了墙体构件动态热性能测试试验台,采用(PCM)PX-27、RT-27这两种常用的相变材料,与典型混凝土空心砌块相结合的方式进行测试分析。各墙体在我国夏季西(东)向墙、南向墙和北向墙的典型室外综合温度条件下分别进行了测试。结果表... 本研究建立了墙体构件动态热性能测试试验台,采用(PCM)PX-27、RT-27这两种常用的相变材料,与典型混凝土空心砌块相结合的方式进行测试分析。各墙体在我国夏季西(东)向墙、南向墙和北向墙的典型室外综合温度条件下分别进行了测试。结果表明,墙体的中部和内部区域通常是放置PCM的合适位置;只有当相变总潜热足够高时(试验中高于251.93 kJ),墙体的外侧成为PCM的最佳位置。此外,保温层主要决定了墙体热流的平均水平,在一定程度上降低了内表面温度和热流的振幅;PCM不仅对温度和热流振幅有较大程度的衰减,而且显著提高了墙体的延迟时间。 展开更多
关键词 相变材料 围护结构 空心砌块 热工性能
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中国现代早期砖拱壳历史遗产之建造组织方式研究——1958年重建工大型空心砌块筒拱厂房设计建造一体化实验回顾
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作者 夏珩 殷嘉悦 张轶伟 《建筑师》 CSSCI 2024年第3期71-77,共7页
揭示节约“三材”约束条件下,重庆建筑工程学院师生探索设计、施工一体化的快速施工方式,是教学与生产实践结合的一次有益尝试。基于历史文献研究、三维图式、口述采访的工作方法,从设计过程、施工组织、机械工具、人员协调等多方面回顾... 揭示节约“三材”约束条件下,重庆建筑工程学院师生探索设计、施工一体化的快速施工方式,是教学与生产实践结合的一次有益尝试。基于历史文献研究、三维图式、口述采访的工作方法,从设计过程、施工组织、机械工具、人员协调等多方面回顾了1958年重建工师生使用大型空心砌块筒拱技术承建江陵厂厂房的史实。它是新中国早期砖薄壳结构谱系中的重要类型,对当下的建造教学也具有参考价值。 展开更多
关键词 重庆建筑工程学院 大型空心砌块筒拱 可移动模架 1958年 教育——生产实践结合
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半干法生产磷石膏空心砌块的性能研究 被引量:1
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作者 封信超 沈莎莎 +1 位作者 陈正强 廖承钰 《新型建筑材料》 2024年第3期15-19,共5页
为推进磷石膏的大宗利用,自主研发了半干法用于生产磷石膏空心砌块,对比了半干法与浇注法的工艺,介绍了半干法的工艺、原理及产品性能。研究显示,采用半干法制备的磷石膏空心砌块脱模时的初始含水率为23.06%,远低于浇注法生产的砌块,且... 为推进磷石膏的大宗利用,自主研发了半干法用于生产磷石膏空心砌块,对比了半干法与浇注法的工艺,介绍了半干法的工艺、原理及产品性能。研究显示,采用半干法制备的磷石膏空心砌块脱模时的初始含水率为23.06%,远低于浇注法生产的砌块,且第6 d即处于干燥状态;断裂荷载和抗压强度在下线码垛时即符合JC/T 698—2010《石膏砌块》的要求,24 h内线性提高,24~72 h因返潮略有降低,此后至144 h平缓提高并基本稳定。产品应在下线码垛至24 h内或第3 d后装车运送用户,不需要晾晒或烘干;夏季生产在脱模后2 h内应适当喷淋,生产时可适当添加二水石膏(废弃产品粉碎料),应在产品下线第3 d后进行砌筑。 展开更多
关键词 半干法 磷石膏空心砌块 含水率 断裂荷载 抗压强度
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再生混凝土空心砌块墙体抗压性能试验研究
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作者 苟周 《江西建材》 2024年第6期45-46,67,共3页
为分析再生混凝土空心砌块墙体的抗压性能,文中对轴心抗压以及偏心受压条件下再生混凝土的破坏模式、承载特性以及墙体的平面变形进行试验研究。结果表明,轴心受压作用下高厚比7.5的试件比高厚比5.4的试件开裂荷载低14.3%;破坏荷载低7.1... 为分析再生混凝土空心砌块墙体的抗压性能,文中对轴心抗压以及偏心受压条件下再生混凝土的破坏模式、承载特性以及墙体的平面变形进行试验研究。结果表明,轴心受压作用下高厚比7.5的试件比高厚比5.4的试件开裂荷载低14.3%;破坏荷载低7.1%。偏心受压荷载作用下高厚比7.5的试件比轴心受压荷载作用下高厚比5.4的试件开裂荷载低21.4%,破坏荷载低4.1%。相同加载模式下,墙体高厚比越高,其承载荷载越低;偏心荷载作用下墙体的承载性能同样开始降低。 展开更多
关键词 空心砌块 再生混凝土 墙体 抗压性能 平面变形
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钛石膏空心砌块力学性能试验及水化机理分析
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作者 杨贺 陈伟 《新型建筑材料》 2024年第6期16-19,共4页
以钛石膏(TG)和脱硫石膏(FGD)作为主要原料制备复合钛石膏,掺加石膏增强剂(GRA),制作钛石膏空心砌块。研究了GRA对复合钛石膏早期强度与凝结时间的影响以及钛石膏空心砌块的力学性能及微观结构。结果表明:当GRA掺量为0.09%,复合钛石膏符... 以钛石膏(TG)和脱硫石膏(FGD)作为主要原料制备复合钛石膏,掺加石膏增强剂(GRA),制作钛石膏空心砌块。研究了GRA对复合钛石膏早期强度与凝结时间的影响以及钛石膏空心砌块的力学性能及微观结构。结果表明:当GRA掺量为0.09%,复合钛石膏符合GB/T 9776—2008《建筑石膏》2.0等级要求。按m(TG):m(FGD):m(GRA)=5000:5000:9制备钛石膏空心砌块,断裂荷载平均值为4122 kN,抗压强度平均值为3.1 MPa,表观密度为591 kg/m^(3),软化系数为0.36。钛石膏空心砌块的水化产物主要为棒状的二水石膏晶体,内部非结晶态铁杂质降低了钛石膏空心砌块的强度。 展开更多
关键词 钛石膏 钛石膏空心砌块 力学性能 耐水性能
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半干法与浇筑法磷石膏空心砌块性能对比研究
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作者 罗通 陈尚伟 +2 位作者 王毅 叶建周 杨厚文 《新型建筑材料》 2024年第10期79-82,91,共5页
对市售半干法与浇筑法磷石膏空心砌块产品的密度、抗压强度进行对比,通过MIP、XRD、SEM对砌块材料进行表征分析。试验结果表明:浇筑法与半干法砌块产品质量均符合JC/T 698—2010《石膏砌块》要求,半干法砌块实心部位密度比浇筑法砌块大4... 对市售半干法与浇筑法磷石膏空心砌块产品的密度、抗压强度进行对比,通过MIP、XRD、SEM对砌块材料进行表征分析。试验结果表明:浇筑法与半干法砌块产品质量均符合JC/T 698—2010《石膏砌块》要求,半干法砌块实心部位密度比浇筑法砌块大43.57%,抗压强度高228.57%。浇筑法及半干法砌块性能主要受材料中拌合水用量影响,多余拌合用水蒸发集中形成0.22~3.47μm晶间孔隙,导致材料密度及强度的下降;由于拌合水用量较少,半干法砌块在加工成型过程中磷建筑石膏易团聚导致砌块均匀性差,在半干法砌块生产中应进一步优化新拌材料的均匀性。 展开更多
关键词 半干法 浇筑法 磷石膏空心砌块 强度 微观形貌
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别墅高精度混凝土空心砌块砌筑及免抹灰技术
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作者 荔鹏波 赵政 +2 位作者 洪荔 王祯勇 叶青 《工程建设与设计》 2024年第20期118-120,共3页
为实现项目的经济效益和环保效益最大化,结合实际施工案例,详细地分析了高精度混凝土空心砌块砌筑与免抹灰施工技术要点。在设置咬槎时,使用高精度砌块能够取得最佳的施工效果。在砌筑施工时,SH薄层砌筑黏结砂浆是其使用的主要施工材料... 为实现项目的经济效益和环保效益最大化,结合实际施工案例,详细地分析了高精度混凝土空心砌块砌筑与免抹灰施工技术要点。在设置咬槎时,使用高精度砌块能够取得最佳的施工效果。在砌筑施工时,SH薄层砌筑黏结砂浆是其使用的主要施工材料,使用SH柔性抗裂内墙腻子完成墙面打底施工,可实现对抹灰空鼓和墙体裂缝问题的高效控制。 展开更多
关键词 高精度 混凝土空心砌块 砌筑 免抹灰 别墅
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大跨度内凹弧形镂空屋盖结构风洞试验及风振分析研究
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作者 王嘉昌 郭武 +2 位作者 何杰 曾兰军 魏笑天 《建筑技术》 2024年第19期2414-2420,共7页
为明确风荷载取值,对大跨度内凹弧形镂空屋盖进行了刚性模型风洞试验,探究了全风向角作用下屋盖风压系数最值的分布规律,分析了典型测点风压系数随风向角变化的特征规律,建立了屋盖的分块体型系数。试验结果表明,大跨度内凹弧形镂空屋... 为明确风荷载取值,对大跨度内凹弧形镂空屋盖进行了刚性模型风洞试验,探究了全风向角作用下屋盖风压系数最值的分布规律,分析了典型测点风压系数随风向角变化的特征规律,建立了屋盖的分块体型系数。试验结果表明,大跨度内凹弧形镂空屋盖在全风向角作用下,风压系数最值在迎风边缘区域远高于中部区域,且主要承受负风压。设计时中部下凹镂空悬索区域应同时考虑风压和风吸作用,两侧延伸桁架区域可仅考虑风吸作用。基于风洞试验得到的风荷载时程,对屋盖结构进行了风振动力分析,结果表明,屋盖风振位移响应以竖直z向为主,上吸和下压风荷载合力分别在120°和240°风向角作用下最大。屋盖的等效静力风荷载在迎风边缘及角部最大,抗风设计时应引起足够重视。 展开更多
关键词 内凹弧形镂空屋盖 大跨结构 风荷载 风洞试验 风振分析 分块体型系数
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不同条件下再生混凝土掺聚苯颗粒空心砌块力学性能研究
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作者 阚倩倩 《砖瓦》 2024年第3期23-26,共4页
为探究掺聚苯颗粒空心砌块在各条件下的力学性能情况,根据不同配合比分别制作标准空心砌块并测定密度、材料强度,探究空心砌块保温隔热性能。研究结果表明:再生细骨料取代率和聚苯颗粒取代率的提升会导致空心砌块抗压强度降低,但抗压强... 为探究掺聚苯颗粒空心砌块在各条件下的力学性能情况,根据不同配合比分别制作标准空心砌块并测定密度、材料强度,探究空心砌块保温隔热性能。研究结果表明:再生细骨料取代率和聚苯颗粒取代率的提升会导致空心砌块抗压强度降低,但抗压强度水平仍满足非承重墙体要求;掺聚苯颗粒后的再生混凝土密度下降,自重减轻,保温隔热性能提升。综合考虑认为,再生细骨料取代率、粗骨料取代率和聚苯颗粒取代率分别取50%、100%和15%时,材料能够在满足保温隔热性能的基础上保障结构强度。 展开更多
关键词 聚苯颗粒 空心砌块 再生混凝土 建筑工程
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Effects of Additives and Coagulant Temperature on Fabrication of High Performance PVDF/Pluronic F127 Blend Hollow Fiber Membranes via Nonsolvent Induced Phase Separation 被引量:3
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作者 Chun Heng Loh Rong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第1期71-79,共9页
Poly(vinylidene fluoride) (PVDF) has become one of the most popular materials for membrane preparation via nonsolvent induced phase separation (NIPS) process. In this study, an amphiphilic block copolymer, Pluro... Poly(vinylidene fluoride) (PVDF) has become one of the most popular materials for membrane preparation via nonsolvent induced phase separation (NIPS) process. In this study, an amphiphilic block copolymer, Pluronic F127, has been used as both a pore-former and a surface-modifier in the fabrication of PVDF hollow fibermembranes to enhance the membrane permeability and hydrophilicity. The effects of 2nd additive and coagulant temperature on the formation of PVDF/Pluronic F 127 membranes have also been investigated. The as-spun hollow fibers were characterized in terms of cross-sectional morphology, pure water permeation (PWP), relative molecular mass cut-off (MWCO), membrane chemistry, and hydrolphilicity. It was obsered that the addition of Pluronic F 127 significantly increased the PWP of as-spun fibers, while the membrane contact angle was reduced. However, the size of macrovoids in the membranes was undesirably large. The addition of a 2nd additive, including lithium chloride (LiC1) and water, or an increase in coagulant temperature was found to effectively suppress the macrovoid for- mation in the Pluronic-containing membranes. In addition, the use of LiC1 as a 2nd additive also further enhanced the PWP and hydrophilicity of the membranes, while the surface pore size became smaller. PVDF hollow fiber with a PWP as high as 2330 L·m-2·h-1·MPa-1, a MWCO of 53000 and'a contact angle of 71 o was successfully fabricated with 3% (by mass) of Pluronic F127 and 3% (by mass) of LiC1 at a coagulant temperature of 25 ℃, which shows better performance as compared with most of PVDF hollow fiber membranes made by NIPS method. 展开更多
关键词 amphiphilic block copolymer pore forming surface modifying additive poly(vinylidene fluoride) hollow fiber membrane
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单因子评价法下的陶粒混凝土空心砌块节能性分析
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作者 侯文丽 周子钰 《价值工程》 2023年第10期134-136,共3页
近年来,建筑行业一直在寻求行业可持续发展的道路上,绿色建筑材料的提出给建筑行业带来了新的发展机遇。目前,对于绿色建筑材料的标准在世界范围内愈发的全面和完善,各地对绿色建筑材料的使用率也稳步上升,更多的建设单位在建筑材料选... 近年来,建筑行业一直在寻求行业可持续发展的道路上,绿色建筑材料的提出给建筑行业带来了新的发展机遇。目前,对于绿色建筑材料的标准在世界范围内愈发的全面和完善,各地对绿色建筑材料的使用率也稳步上升,更多的建设单位在建筑材料选择上开始选择使用绿色建材,人们对绿色建材的接受程度和认知日益提高。绿色建材的评价体系是评价材料是否满足绿色建材的重要因素,通过对材料的各项指标进行比对、测试等从而确定材料是否达标。本文从绿色建材的发展角度出发,利用单因子评价法对绿色建筑材料陶粒混凝土空心砌块进行节能性分析,根据实际案例的使用情况判别该材料的应用状况,阐述该绿色建材的应用效果,助力绿色建筑的长效发展。 展开更多
关键词 绿色建材 单因子评价法 陶粒混凝土空心砌块 节能性
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承重型横孔连锁混凝土空心砌块砌体抗压性能研究
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作者 安静 梁冠军 《菏泽学院学报》 2023年第2期89-93,106,共6页
砌块结构是常用的建筑结构形式之一.承重型横孔连锁混凝土空心砌块的技术门槛较低,可以在多种建筑施工场景中使用,为了保证其应用后的稳定性,分析了砌体抗压性能.选择QT-250、QH-250、QH-300三种类型砌块作为试件,对照试件的生产尺寸,... 砌块结构是常用的建筑结构形式之一.承重型横孔连锁混凝土空心砌块的技术门槛较低,可以在多种建筑施工场景中使用,为了保证其应用后的稳定性,分析了砌体抗压性能.选择QT-250、QH-250、QH-300三种类型砌块作为试件,对照试件的生产尺寸,设定了砌筑砂浆的三种强度类型.采用试压机作为加载受压设备,对砌块砌体进行加压测试,并记录承压数据,以此来分析抗压强度.不同类型试件的抗压强度测试结果表明:不同砌块类型的抗压强度不同,当砂浆强度等级为ER-15、砌块类型为QT-250时,混凝土空心砌体的抗压强度最佳. 展开更多
关键词 承重型混凝土 空心砌块 砌块结构 横孔连锁混凝土 抗压性能
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