共查询到20条相似文献,搜索用时 62 毫秒
1.
不同配合比模压成型木纤维增强水泥板力学性能的研究 总被引:2,自引:0,他引:2
研究了不同木纤维掺量及掺加细石英砂、粉煤灰、PP纤维、木粉、云母片、膨胀珍珠岩后对模压成型水泥板材力学性能的影响,同时探讨了压蒸养护与标准养护下不同龄期的力学性能差异。结果表明,掺加木纤维后板材的延性有所改善,强度则随着纤维掺量的增加而降低;板材强度随着石英砂和粉煤灰掺量增加而降低;PP纤维具有一定的增韧效果;掺加木粉会降低板材强度且没有增韧效果;云母片对板材的韧性和强度影响不大,而使板材密度增加较大;膨胀珍珠岩在适当掺量下对板材强度影响不大,但可以降低密度;压蒸养护下板材的强度有较大的改善。 相似文献
2.
3.
《建筑砌块与砌块建筑》2015,(4)
建筑废弃物再生原料发泡混凝土(简称:再生原料发泡混凝土)是以水泥为主要胶凝材料、建筑废弃物再生原料为骨料、通过化学发泡工艺制成的一类轻质多孔材料。本文系统研究了外加剂品种及掺量对再生原料发泡混凝土性能的影响。结果表明:为保证发泡效果和成型稳定性,对于B07级再生原料发泡混凝土,速凝剂适宜掺量为2.68%,对于B08级再生原料发泡混凝土,速凝剂适宜掺量为2.28%。随着稳泡剂掺量增加,再生原料发泡混凝土发泡稳定性明显增加,发泡高度60cm时无冒泡或下沉现象,但掺加稳泡剂后,再生原料发泡混凝土抗压强度略有降低,稳泡剂适宜掺量为0.1%。掺加水镁石纤维或PP纤维可明显改善再生原料发泡混凝土的收缩开裂,水镁石纤维效果优于PP纤维。 相似文献
4.
研究了不同掺量PVA纤维、PP纤维和玻璃纤维对试件力学性能的影响以及不同钼尾矿替代率对纤维水泥制品力学强度的影响,并通过试验确定了纤维水泥板的最优配合比。结果表明,以PVA为增强纤维的试件性能优于PP纤维和玻璃纤维。采用模压成型,以PVA纤维和木浆纤维作为复合增强材料,掺钼尾矿所制备的纤维水泥板的抗折强度均高于未掺加钼尾矿的,且当钼尾矿替代量为20%时,其抗折强度最高。 相似文献
5.
通过调整玻璃纤维(GF)和聚丙烯纤维(PPF)掺量,在其他材料和配比不变的情况下,以800、1200 kg/m3两种表观密度的微孔混凝土为基本对象,2种纤维按0、1.0、1.5、2.0、2.5 kg/m3单掺以及按1∶2、1∶1、2∶1体积比复掺,对比不同表观密度微孔混凝土力学性能的变化。结果表明:随着PPF掺量的增加,抗压强度先提高后降低,其余试验组抗压强度大体上均呈逐渐提高的趋势。表观密度800 kg/m3时单掺较复掺抗压强度明显提高。随着表观密度增大至1200 kg/m3,复掺纤维组的强度开始优于单掺纤维组,特别是早期强度提升较明显。所有试验组的抗压强度均随表观密度的增大而提高。 相似文献
6.
7.
《建筑节能》2021,(6)
以P·O 42.5级水泥为胶凝材料、双氧水为发泡剂,掺加聚乙烯醇纤维,制备一种发泡水泥/聚乙烯醇纤维复合保温材料,探讨聚乙烯醇纤维用量对复合材料性能的影响。结果表明,随着聚乙烯醇纤维用量的增加,发泡水泥/聚乙烯醇纤维复合材料的干密度呈现先减小后增大的趋势。当聚乙烯醇纤维用量为2.87 g时,干密度低至208.37 kg/m~3,当聚乙烯醇用量进一步增大至3.37 g时,干密度增大至216.16 kg/m~3,这是由于纤维量过多时,较难分散开,干密度反而增大。吸水率整体呈现增大趋势,但聚乙烯醇纤维增加到2.37 g时,其吸水率略有下降。抗折强度和抗压强度变化趋势类似,均为先增大后减小,聚乙烯醇纤维用量高于2.87 g时,力学强度下降,在研究范围内以聚乙烯醇纤维用量控制在2.87 g为宜。 相似文献
8.
以水泥和粉煤灰为复合胶凝材料,采用泡浆分开混合法制备发泡水泥轻质保温材料,研究不同泡沫掺量对发泡水泥轻质保温材料干密度、抗压强度及其导热系数的影响。结果表明:当泡沫掺量不超过2250ml/kg时,发泡水泥轻质保温材料具有较低的干密度、较高的抗压强度以及较小的导热系数,并满足GB11968-2006《蒸压加气混凝土砌块》对其性能的要求。利用扫描电子显微镜对试样内孔结构及其分布进行微观分析,探讨孔结构及其分布对发泡水泥轻质保温材料的作用机理。 相似文献
9.
将废弃发泡水泥加工成轻骨料,掺入发泡水泥浆中制备轻骨料泡沫混凝土,测试其干密度、抗压强度、比强度、软化系数、导热系数和质量吸水率等性能。结果表明,干密度随着轻骨料掺量的增加先增加后减少,抗压强度、比强度、软化系数和导热系数均随着轻骨料掺量的增加而减少,质量吸水率则随着轻骨料掺量的增加而增加。当废弃发泡水泥轻骨料的掺量为60 kg/m~3时,轻骨料泡沫混凝土比强度高、导热系数小、软化系数高,综合性能优异。 相似文献
10.
11.
Lei Peng George Hadjisophocleous Jim Mehaffey Mohammad Mohammad 《Fire Safety Journal》2010,45(6-8):392-399
This paper reviews fire resistance tests of double shear timber connections, including wood–wood–wood connections with nails, bolts and dowels and wood–steel–wood connections with bolts and dowels. Test data are used to assess the effects of the load ratio and the member geometry on the fire resistance of timber connections. New relationships are proposed and analysis results show good agreement with the test results. Design rules presented in Eurocode 5 are also discussed and compared with the proposed calculation method. 相似文献
12.
《中国室内装饰装修天地》2006,(1):92-99
美国SOM设计所(Skidmore.Owings&Merrill)将乔冶中岛(George Nakashima)的设计理念注入到凯悦国际酒店集团新芝加哥总部设计的项目中。[编者按] 相似文献
13.
14.
Alfredo S. Ribeiro Abílio M.P. de Jesus António M. Lima José L.C. Lousada 《Construction and Building Materials》2009,23(8):2738-2745
The application of the concept of glued-laminated wood (glulam) to improve the mechanical properties of the solid wood of the maritime pine (Pinus pinaster) is the subject of this work. Two reinforced glued-laminated wood beams are proposed and assessed. The first is based on a concept of laminated wood composite with fiber glass; the second is based on the application of pultruded lamellas glued to the most stressed tensile region of the glued-laminated beams. In order to demonstrate the potential of the proposed strengthening solutions, a comparison between their mechanical behaviors and the mechanical behaviors of the conventional glued-laminated and solid beams are performed. Static load–deflection curves, an equivalent Young’s modulus, the ultimate strain and modulus of rupture are determined using 3-point quasi-static bending tests. In general, it is demonstrated the beneficial effect of the proposed strengthening solutions both in terms of resistance and ductility. 相似文献
15.
16.
17.
The dynamics of burning of wood charcoal in an air stream is examined both experimentally and theoretically. To simplify the theory, an experimental arrangement approximating a one dimensional phenomenon was adopted. The theory includes conduction in the solid, chemical reactions and heat release at the surface, and heat and mass transfer in the gas boundary layer above the surface. The molar CO/CO2 ratio is measured. The theory predicts surface temperature, solid temperature distribution and burning rate within experimental error. An effective reaction rate formula is developed. 相似文献
18.
通过1∶2比例穿斗式木构架结构和轻型木结构模型的振动台试验,对这两种结构的抗震性能进行了研究。结果表明:穿斗式木构架在峰值加速度在0~0.5g的地震激励下,柱顶水平加速度反应会减小,动力放大系数在0.46~0.57之间,柱顶位移会增大,在输入峰值加速度大于0.4g后,柱与础石之间会产生较大的滑移,卯榫节点也会产生较大变形,从而耗散大量的地震能量,使得该结构具有明显的减震效果;轻型木结构模型则在峰值加速度大于0.4g地震激励下,柱顶加速度动力放大系数大于1,且轻型木结构模型在峰值加速度0.5g地震激励下,仍处于弹性状态。 相似文献
19.
The influence of three fire retardant agents: Polichron, Pyrolak W-10, and Pyrolak W-10 + Pyrolak W-1 on smoke density of pine wood, plywood, soft hardboard and tough hardboard was investigated. Surface samples of 25 cm2 (5 × 5 cm) were used and the heat flux was varied over the range of 1.0 to 4.0 W/cm2.
Reference: Tadeusz Cisek and Jacek Piechocki, Influence of Fire Retardants on Smoke Generation from Wood and Wood Derived Materials,Fire Technology, Vol. 21, No. 2, May 1985, p. 122. 相似文献
20.
The authors conducted a series of wood crib burnout tests to determine the emissivity and convective heat transfer coefficient
of wood crib flames. These values can be used to calculate heat transfer between flames and exposed structural members. 相似文献