浅析泡沫混凝土在建筑工程中的应用

改革开放以来,我国社会经济得到了快速的发展,我国建筑各行各业也得到了不断地发展,节能型建筑材料的创新和应用受到了人们的高度关注,我国大力地发展节能、保温、隔热和轻体等新型材料。由于泡沫混凝土具有轻质、耐火、隔热、隔音以及保温等优点,通过充分地利用泡沫混凝土的良好特性,可以扩大泡沫混凝土在建筑工程中的应用领域,可以使工程进度得到进一步地加快,以此提高工程的质量。目前,泡沫混凝土主要应用于屋面泡沫混凝土保温层现浇、泡沫混凝土面块、泡沫混凝土轻质墙板以及泡沫混凝土补偿地基。因此,在建筑工程节能墙体中得到了广泛的应用。本文将对泡沫混凝土在建筑工程中的应用进行分析、探讨,以此为同类工程提供有力的参考依据。     

有机泡沫保温建筑材料的现状与发展方向

阐述有机泡沫保温建筑材料的品种?制备方法?组成以及特性,分析主要有机泡沫保温建筑材料施工技术特征?使用缺陷与应用范围?探讨新型有机泡沫保温建筑材料的研究方法?介绍国内有机泡沫保温建筑材料的市场前景与行业发展状况,展望有机泡沫保温建筑材料的研究发展趋势和应用前景,指出有机泡沫保温建筑材料技术的未来发展方向?     

泡沫混凝土的制备工艺及研究进展

泡沫混凝土是一种新型的节能环保型建筑材料,泡沫混凝土的主要特性有:轻质、保温隔热性能好、隔音性能好、防水性能强、环保性能好等;研究了泡沫混凝土的制备原理以及制备工艺;综合论述了泡沫混凝土在国内外应用的研究进展;指出了泡沫混凝土应用的问题,并对前景进行了展望。     

泡沫混凝土在屋面结构中的施工技术

结合工程实例,从泡沫混凝土制备方法、施工工艺、施工要点和注意事项等方面,对泡沫混凝土在屋面结构中的应用进行了分析,并将泡沫混凝土与常规的建筑材料施工成本进行对比,指出使用泡沫混凝土作为屋面结构中的找平层和保温层具有良好的经济效益和社会效益,值得在建筑市场中推广应用。     

泡沫混凝土在房屋建筑中的应用

本文较详细地介绍了泡沫混凝土的特性及其制品的生产与应用，指出泡沫混凝土是一种具有很大发展前途的新型建筑材料，应大力开发推广。     

无机复合泡沫保温板燃烧性能探析——GB 8624-2012标准解读

依据GB 8624-2012《建筑材料及制品燃烧性能分级》标准规定,对无机复合泡沫保温板类制品的燃烧性能,与按照GB 8624-1997《建筑材料燃烧性能分级方法》标准的测试结果进行对比分析,给出了一些应用建议。     

泡沫混凝土在房屋建筑中的应用

本文较详细地介绍了泡沫混凝土的特性及其制品的生产与应用，指出泡沫混凝土是一种具有很大发展前途的新型建筑材料，应大力开发推广。     

拜耳推出聚氨酯保温板升级产品PIR板材

本刊讯 在不久前召开的第八届中国国际聚氨酯展览会上．德国拜耳公司重点推荐了一款聚氨酯保温板的升级产品——PIR保温板外墙外保温系统。与普通PUR板材相比．PIR板材的保温性能和防火性能更加优异。据估计,建筑中每使用1kg聚氨酯,在其平均使用寿命期内可减排二氧化碳755kg。     

泡沫混凝土在我国的应用

泡沫混凝土是一种具有保温隔热、防火、防水、隔热、吸音、轻质、无毒无害、节能多种优点于一身的新型建筑材料,本文就泡沫混凝土在我国的应用领域进行了全面的总结。     

粉煤灰制泡沫玻璃

粉煤灰制泡沫玻璃吴方贵谢建忠（江西萍乡市硅酸盐研究所）（江西萍乡煤炭工业学校）泡沫玻璃是一种新型建筑材料。它是以粉煤灰为主要原料烧制的，密度在５００～７００Ｋｇ／ｍ３之间，导热率０．１７～０．２０ｗ／ｍ·ｋ，抗压强度５～６ＭＰａ，耐酸碱的新材料，具有...     

Flame retardants in the indoor environment -- Part II: release of VOCs (triethylphosphate and halogenated degradation products) from polyurethane

Organophosphate esters, halogenated and non-halogenated, are frequently used for fire protection of building materials. With regard to toxicological profiles it is desired to avoid human exposure in the indoor environment. Moreover, some hazardous volatile organic compounds detected in indoor air are directly linked to the utilization of flame retardants. In this study, different polyurethane (PUR) products for building and indoor use treated with organophosphate flame retardants were tested in 1 m(3) emission test chambers. Emissions of flame retardants and degradation products were measured under living conditions. A PUR hard foam sample showed area-specific emission rates >100 microg/m(2) h for the compound triethylphosphate. During the tests several chlorinated degradation products of organophophorous flame retardants could be identified in the chamber air.     

Fire Performance of Sandwich Panels in a Modified ISO 13784-1 Small Room Test: The Influence of Increased Fire Load for Different Insulation Materials

Four sandwich panel rooms were constructed as prescribed in the ISO 13784-1 test. However, the construction followed normal industry practice, and the panels were also subjected to the kinds of damage typically found in commercial premises, although such damage may not typically be concentrated in such a small room. The fire load was increased to simulate fires actually occurring in commercial premises by stepping up the propane burner output from the usual maximum of 300–600 kW, and by placing a substantial wooden crib in two of the rooms. The results showed significant differences in fire growth rate and burning behaviour between those panels filled with polyisocyanurate (PIR) and those filled with stone wool in both the experiments without and with the wooden crib. Most significantly, the PIR pyrolysis products caused earlier ignition (by radiation from above) of the wooden crib 11 min into the experiment (1 min after the burner was stepped up to 300 kW), whereas the crib ignited 22 min into the test (2 min after the burner had been stepped up to 600 kW, which is beyond the test standard both in time and heat input) for the stone wool panels. This interaction between building and contents is most often ignored in fire safety assessments. After a few minutes, the PIR pyrolysis products that escaped outside the room, from between the panels, ignited. The extra thermal exposure from the PIR-fuelled flames distorted the panels, which in turn exposed more PIR, resulting in large flames on both the inside and outside of the enclosure. From a fire safety perspective this is most important as it shows that with the large fire loads that are commonly found in commercial premises, steel-faced PIR filled panels are not capable of acting as fire barriers, and may support flame spread through compartment walls and ceilings. In addition, the PIR panelled rooms produced very large quantities of dense smoke and toxic effluents, whereas the stone wool panelled rooms produced small amounts of light smoke of lower toxicity. Furthermore, the experiments showed that modifications to the standard test can lead to extremely different outcomes for some of the products. As the modifications simulated real-life situations, it seems important to discuss whether the standard is robust enough for property safety scenarios encountered in industrial premises.     

Fire safety aspects of PCM-enhanced gypsum plasterboards: An experimental and numerical investigation

New trends in building energy efficiency include thermal storage in building elements that can be achieved via the incorporation of Phase Change Materials (PCM). Gypsum plasterboards enhanced with micro-encapsulated paraffin-based PCM have recently become commercially available. This work aims to shed light on the fire safety aspects of using such innovative building materials, by means of an extensive experimental and numerical simulation study. The main thermo-physical properties and the fire behaviour of PCM-enhanced plasterboards are investigated, using a variety of methods (i.e. thermo-gravimetric analysis, differential scanning calorimetry, cone calorimeter, scanning electron microscopy). It is demonstrated that in the high temperature environment developing during a fire, the PCM paraffins evaporate and escape through the failed encapsulation shells and the gypsum plasterboard's porous structure, emerging in the fire region, where they ignite increasing the effective fire load. The experimental data are used to develop a numerical model that accurately describes the fire behaviour of PCM-enhanced gypsum plasterboards. The model is implemented in a Computational Fluid Dynamics (CFD) code and is validated against cone calorimeter test results. CFD simulations are used to demonstrate that the use of paraffin-based PCM-enhanced construction materials may, in case the micro-encapsulation shells fail, adversely affect the fire safety characteristics of a building.     

Energy distribution analysis in full-scale open floor plan enclosure fires

Within a fast evolving built environment, understanding fire behaviour and the thermal exposure upon structural elements and systems is key for the continued provision of fire safe designs and solutions. Concepts of fire behaviour derived from research in enclosure fires has traditionally had a significant impact in general building design. At present, open floor plan enclosures are increasingly common – building design has drastically drifted away from traditional compartmentalisation. Nevertheless, the understanding of fire behaviour in open floor plan enclosures has not developed concurrently. The compartment fire framework, first conceived for under-ventilated fires in cubic compartments, has remained as standard practice. Although energy conservation within the enclosure was the basis for the current compartment fire framework that defines under-ventilated enclosure fires, little effort has been carried towards understanding the distribution of energy in design frameworks conceived for open floor plan enclosure fires. The work presented herein describes an analysis of the energy distribution established within an experimental full-scale open floor plan enclosure subjected to different fire modes and ventilation conditions. The results aim to enable the designer to estimate the fraction of the total energy released during a fire noteworthy to structural performance.     

Experimental study on the influence of different thermal insulation materials on the fire dynamics in a reduced-scale enclosure

Four scaled (1:5) fire experiments with two identically classified types of commercially available sandwich panels incorporating either stone wool (SW) or polyisocyanurate (PIR) foam as cores were conducted using a modified version of the ISO 13784-1 (Reaction to fire tests for sandwich panel building systems — Part 1: Small room test) standard. This was to assess the suitability of scaled experiments for assessing sandwich panel fire behavior. In the modified version of the test standard (scaled and full experiments), the fire severity was increased to simulate fires that could occur in commercial premises. This was achieved by prolonging and doubling the heat release rate output of the gas burner at the end of the experiments. Furthermore, non-structural damages such as screw-hole damages were applied to the enclosures to reflect real life observations.The results showed differences in the fire behavior, depending on whether the enclosures were constructed of panels filled with SW or PIR insulation material. The mass losses of the insulation materials showed significant contribution from the PIR cores, regardless of fire load and the non-structural damage.The qualitative behavior with respect to the “flashover” failure criterion, as stated in the ISO 13784-1, was successfully obtained in all of the scaled experiments. As such, the scaled experiments mimicked the behavior of the full scale SW experiments to a satisfactory degree. However, the PIR compartments failed considerably earlier in the full scale tests than in the scaled experiments. Therefore, it can be concluded that when the energy contribution from the core material remained negligible compared to the gas burner, the measured parameters matched quite well. Therefore, if the insulating core material does not dominate the fire dynamics of the compartment and the energy from the gas burner dictates the fire scenario then the scaled set-up will predict the temperature in the full scale compartment. Based on this and with further development with respect to, especially, time, this kind of scaled experiments could be a valuable testing method for assessment of the behavior of sandwich panel, and therefore merit further studies and eventually increased use.     

Predicting the Fire Dynamics of Exposed Timber Surfaces in Compartments Using a Two-Zone Model

There is an increasing desire to use more engineered timber products in buildings, due to the perceived aesthetics of timber and desire for more sustainable architecture. However, there are concerns about fire performance of these products especially in taller buildings. This has led to renewed research to understand the behaviour of timber surfaces in compartments exposed to fire. This paper describes a two-zone calculation model for determining the fire environment within a compartment constructed from timber products where varying amounts of timber are exposed on the walls and ceiling. A set of eight full-scale compartment experiments previously reported in the literature are used to assess the capability of the model. The fire load energy density in the experiments ranged from 92 MJ/m² to 366 MJ/m² comprising either wood cribs or bedroom furniture with the largest compartment having dimensions 4.5?×?3.5?×?2.5 m high with an opening 1.069 m wide?×?2.0 m high. The experiments were ventilation-controlled. It is shown that the model can be used to provide conservative predictions of the fire temperatures for compartments with timber exposed on the walls and/or ceiling as part of an engineering analysis. There are several limitations that are discussed including the need to consider the debonding of layers in the case of cross-laminated timber. It is recommended that further benchmarking of the model be done for different ventilation conditions and with engineered timber products where debonding does not occur. This will test the model under a wider range of conditions than examined in this paper.     

Finite Element Modelling of Post-tensioned Timber Beams at Ambient and Fire Conditions

An increased environmental conscientiousness in society and the abundance of timber in Canada has inevitably led to the desire for more timber construction. In order to increase the opportunity for timber products in construction, novel building systems such as post-tensioned (PT) timber have been developed. Limited development on numerical modelling has been done on PT timber systems for the optimization of design for fire performance. In industry, there is need for a modelling software capable of approximating complex timber system behaviours that is accessible to practitioners. This research program serves to evaluate the current capabilities or shortcomings of modelling PT timber in both ambient and fire conditions, and to develop a methodology for analyzing the performance of the system. Several numerical models of PT timber beam tests are developed and validated using general purpose FEM software ABAQUS. This software is a good research tool and the lessons learned may be used to refine an accessible model for practitioners. Various material definitions are compared including isotropic and orthotropic models. The numerical models show highly promising results for demonstrating the loading and failure behaviour of PT timber beams. Material property directionality is paramount, captured best with the use of Hill’s Potential Function for non-elastic behaviour. Ambient beam tests are modelled with accurately demonstrated load–deflection behaviour and peak loads are computed to within 5% of experimentally recorded values. For PT timber beam standard fire furnace tests, beam failure times are modelled within 3 min of experimental beam failure times for various fire exposure durations (about 5%), and load–deflection behaviour and failure mechanisms are accurately demonstrated. Thermal gradients align with the recorded thermocouple readings and char depths are computed within 4 mm of the observed layers.     

A级防火等级外墙外保温系统推荐

针对国家发布的建筑保温材料性能要求,甄选了国内的4种A级防火外保温系统:STP超薄绝热保温板外墙外保温系统、发泡陶瓷板外墙外保温系统、玻化微珠无机保温砂浆外墙外保温系统和岩棉板薄抹灰外墙外保温系统,分析了4种外保温系统的利弊,提出了各个系统使用的注意点,并提供了工程选用的推荐方案.     

Fire Behavior of Alternate Building Materials—Part I—RMP

Polymers are fast replacing the conventional building materials, mainly because of their scarcity and attractive properties. However, users are hesitant to accept these alternate building materials as the polymers are considered to be associated with fire hazards. Red mud plastics (RMP) is one such polymer which is finding acceptance albeit slowly. Fire behaviour of RMP is discussed and compared with some conventional materials with a view to present it as a viable alternate.     

Full-scale natural fire tests on gypsum lined structural insulated panel (SIP) and engineered floor joist assemblies

SIPS are formed from the lamination of two oriented strand board (OSB) facing plates and a highly insulating polymer-based foam such as expanded polystyrene (EPS) or polyurethane (PUR). The resulting lightweight panels are typically used as primary load-bearing compression elements for buildings such as domestic dwellings, apartment blocks, schools and hotels.The regulatory fire performance of SIPS, like many systems, is assessed via a standard fire test. However, it is widely accepted that this is merely a comparative method for determining the relative performance of one product when compared to another; hence, it gives little indication of a component's likely behaviour in a real fire. With this in mind BRE Global, with support from the UK Department for Communities and Local Government (CLG), have undertaken a research programme to determine the performance of SIPS subject to realistic fire conditions.The research programme exposed four two storey SIP buildings to natural fire scenarios using timber cribs. Two buildings were constructed with EPS core SIPS. The other two were constructed with PUR core SIPS. Each material set was subdivided by passive fire protection specification (PFP). These were specified on the basis of 30 and 60-min fire resistance.The experiments highlighted a number of weaknesses in the system performance of SIP structures with engineered floors. Firstly, where PFP is under specified or poorly installed, collapses of the engineered floor plate are very likely. Mechanisms for fire spread were also identified where fitting details were not appropriately sealed. In addition, there appeared to be little appreciable difference in the behaviour of buildings formed with EPS or PUR core SIPS. Finally, a number of system redundancies and alternative load paths were identified, which prevented total collapse of any of the test buildings.