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EPS板保温系统裂缝问题的数值分析
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摘要
随着城市化进程的加快和居民生活质量的提高,我国建筑能耗总量呈逐年上升趋势,单位面积采暖能耗相当于气候条件相近发达国家的3倍以上,建筑节能工程作为国家十大重点节能工程之一,是节能减排的重点领域。而建筑外墙的保温隔热性能差是建筑能耗高的主要原因之一
     在中原地区尤其是河南省EPS板薄抹灰外墙外保温系统凭借其多方面的优势,在建筑节能尤其是既有建筑的节能改造中应用较广泛。然而,EPS板薄抹灰外墙外保温系统自身的材料性能及与主体结构的材料性能差异较大,在外界不利环境因素及气候条件不断变化下很容易出现裂缝脱落等问题,特别是在夏季高温时骤降暴雨、冬季加热后冷冻极端环境下门窗等洞口附近发生裂缝的几率更大。
     本文在河南省重大公益科研计划项目(081100910400)、郑州市重大科技计划项目(082SGZS32079)以及郑州大学研究生科学研究基金(重点类A181)课题支持的背景下,采用有限元数值模拟方法针对EPS板保温系统裂缝及脱落现象进行研究,探讨开裂前的温度场分布,变形情况及应力分布规律,进而提出防裂的对策及建议,主要做了以下工作:
     1)选取郑州市某多层砌体结构住宅建筑外墙中的一个带窗户洞口的典型开间为研究对象建立有限元模型,采用主卧、次卧及客厅外墙常见的立面尺寸,按照规范规定验证EPS板外保温复合墙体厚度方向尺寸满足郑州地区目前的节能标准。文中主要考虑热传导和热对流对外保温复合墙体的影响,选定边值条件,确定材料性能参数,选用耦合场单元进行网格划分。分析中把研究对象看成是立起来的薄板,提出其基本假定,应用直接法进行有限元计算。
     2)探讨了夏季极端高温后骤降暴雨环境下的EPS板薄抹灰外墙外保温系统热—结构耦合反应,分析其温度场变化、变形情况及应力场分布,探讨裂缝的成因及规律。经过分析发现,聚苯板具有良好的保温隔热效果;窗洞附近变形最大,材料先膨胀后收缩,如果适应不了这种变化,很容易出现裂缝;聚苯板与砂浆的交界处出现应力突变,容易产生应力集中或裂纹。从外保温复合墙体中取出一个微平行六面体,探寻水平裂缝、竖向裂缝和窗洞四角斜裂缝及脱落现象产生的原因。
     3)探讨了冬季加热后冷冻极端环境EPS板薄抹灰外墙外保温系统热—结构耦合反应,与夏季高温后骤降暴雨极端环境进行比较,重点针对窗户洞口附近进行分析其温度、变形及应力情况发现,聚苯板层与砂浆层的交界处变形不协调,应力值突变,很容易产生裂缝甚至脱落;温度升高产生压应力,温度降低产生拉应力,拉应力超过材料的抗拉强度是裂缝产生的根源;温差越大,变形越大,应力也越大,因此冬季冷冻环境是极易产生裂缝的环境。
     4)针对文中的计算结果分析,以及裂缝形成的原因,有针对性地提出一些量化的防止EPS板薄抹灰外墙外保温系统裂缝产生的措施及建议,改善目前保温系统裂缝现象严重的问题。
With the accelerated urbanization process and the improvement of the quality of resident life, the total building energy consumption in China is increasing year by year. The heating energy consumption per unit area is equivalent to 2 to 3 times of the developed countries with similar climatic conditions. Building energy conservation as one of ten energy conservation project is the key area of energy saving. The poor thermal insulating property of the exterior walls is one of the main reasons for building high energy consumption.
     In central China, especially Henan Province, EPS board exterior wall insulation system, with its many advantages, is more extensively applied in building energy efficiency, especially of existing buildings for energy saving. However, the material properties of EPS board exterior wall insulation system itself and the main structure are quite different. So they are likely to cracks or get off in the external negative factors and changing climatic conditions. Especially in summer sudden dropped heavy rain in high temperature and in winter freezing after heated, the probability of crack is larger near the hole of windows and doors under extreme conditions.
     In this paper, based on major public research projects in Henan(081100910400) and major science and technology projects in Zhengzhou(082SGZS32079), adopting the ways of finite element numerical simulation, to have a study of the cracks and get off phenomenon directed towards the EPS board thermal insulation system, to examine pre-crack temperature distribution, deformation and stress distribution, and puted forward measures and suggestions for cracking, the main work as follows:
     1)Selected a typical bay with a window hole of the external wall of a residential multi-storey masonry structure as the study object, seted up finite element model, calculated thickness of external insulation composite wall in accordance with the energy saving standard in Zhengzhou, then selected material properties, proposed basic assumptions, used coupling field unit to mesh.
     2)Simulated heat—structure coupling reaction of EPS board exterior wall thermal insulation system in summer rain environment after extreme high temperature, analyzed the temperature change, deformation and stress distribution, investigated the formation and rules of crack. The analysis founded that polystyrene board had a good insulation effect; and the maximum deformation was near windows, the material was contraction after the first expansion, if not adapted to such changes, it was prone to cracking; and finded the causes of vertical cracks, horizontal cracks and diagonal crack in the corners or windows.
     3) Simulated heat—structure coupling reaction of EPS board exterior wall thermal insulation system in winter frozen after heating, and compared with the result of the sudden drop in rainfall after high temperature in summer extreme environments, focusing on the windows nearby to analyze the temperature, deformation and stress. The analysis founded that, at the junction of polystyrene board layer and the mortar layer, the deformation uncoordinated, the value of stress was a mutation, it was easy to crack or even fall off; higher temperature produced press stress, lower temperature generated tensile stress, that tensile stress exceeded the tensile strength was the crack source; difference in temperature the greater, the deformation the greater, the greater the stress, so the environment frozen in winter was easily crack.
     4) Through the analysis, it concluded with EPS board exterior wall insulation system cracking measures and recommendations, and improved the questions of cracks and falling.
引文
[1]武涌,刘长滨,刘应宗,等.中国建筑节能管理制度创新研究[M].北京:中国建筑工业出版社,2007:16.
    [2]清华大学建筑节能研究中心著.中国建筑节能年度发展研究报告2007[M].北京:中国建筑工业出版社,2007:3.
    [3]杨惠忠.建筑节能新技术研究与工程应用[M].北京:中国建筑工业出版社,2009.
    [4]李青.建筑干粉保温砂浆制备及性能研究[D].长沙:湖南大学,2008.
    [5]童丽萍.从能源危机看建筑节能的必然趋势[J].郑州大学学报(理学版),2008,40(4):105-109.
    [6]河南省建设厅.河南省“十一五”建筑节能专项规划[R].豫建科外[2006]16号文件,2006.
    [7]中华人民共和国国家发展和改革委员会.中华人民共和国国家节能中长期发展规划[EB/OL].[2004-11-25].http://www.sdpc.gov.cn/xwfb/t20050628_27571.htm.
    [8]马保国.外墙外保温技术[M].北京:化学工业出版社,2008:17.
    [9]刘志军.外墙外保温技术浅析[J].山西建筑,2007,33(32):252~255.
    [10]雒伟民.建筑外墙外保温技术及其发展趋势[J].建筑工程,2005,(1):272.
    [11]Aynur Ucar, Figen Balo. Determination of the energy savings and the optimum insulation thickness in the four different insulated exterior walls[J]. Renewable Energy,2010,35(1): 88~94.
    [12]王丽.三种薄抹灰外墙外保温系统的比较和应用[J].山西建筑,2009,35(5):227~229.
    [13]M.C. Swinton, W. Maref, M.T. Bomberg, M.K. Kumaran, N. Normandin. In situ performance evaluation of spray polyurethane foam in the exterior insulation basement system (EIBS)[J]. Building and Environment,2006,41 (12):1872~1880.
    [14]河南省工程建设标准设计管理办公室.1)BJT19-20-2005 05系列工程建设标准设计图集——外墙外保温构造(05YJ3-1)[S].北京:中国建筑工业出版社,2005,10.
    [15]王俊岭.关于郑州市外墙外保温体系几个问题的研究[D].天津:天津大学建筑学院,2007.
    [16]Erich Cziesielski Frank Ulrich Vogdt编著.外墙外保温系统中的质量问题及对策[M].汪峻峰,译.北京:机械工业出版社,2007.
    [17]Jan Toman, Alena Vimmrova, Robert Cerny. Long-term on-site assessment of hygrothermal performance of interior thermal insulation system without water vapour barrier[J]. Energy and Buildings,2009,41(1):51~55.
    [18]Zbysek Pavlik, Robert Cerny. Hygrothermal performance study of an innovative interior thermal insulation system[J]. Applied Thermal Engineering,2009,29(10):1941~1946.
    [19]J. Sadauskiene, V. Stankevicius, R. Bliudzius, A. Gailius. The impact of the exterior painted thin-layer render's water vapour and liquid water permeability on the moisture state of the wall insulating system[J]. Construction and Building Materials,2009,23(8):2788~2794.
    [20]赵海南,王景学,金恒刚.聚笨板薄抹灰外保温施工中的技术问题[J].低温建筑技术,2003,93(3):80~81.
    [21]Nelson. Joint movement of a panelized EIFS wall system. ASTM Special Technical Publication,1995:294~360.
    [22]Williams. Monitoring joint movement in a panelized EIFS building. ASTM. Special Technical Publication,1995:307~3206.
    [23]Gerard FLEURY. Quality Requirement for the EIFS in France, CSIB 1992.
    [24]李为一,郭晔华.EPS板薄抹灰外墙外保温系统质量病害及防治[J].平顶山工学院学报.2007(01):70-72.
    [25]吴美升,王微微,孙洪明.外墙外保温系统开裂问题分析[J].新型建筑材料,2007(05).67~68.
    [26]李红梅.混凝土小型空心砌块建筑温度场与温度裂缝分析[D].杭州:浙江大学建筑工程学院,2004.
    [27]吴文涛.砌体结构温度裂缝的研究[D].天津:天津大学建筑工程学院,2004.
    [28]叶甲淳.混凝土小型空心砌块建筑裂缝控制的温度效应研究[D].杭州:浙江大学建筑工程学院,2003.
    [29]王培铭.商品砂浆[M].北京:化学工业出版社,2008:109.
    [30]马保国,郝先成,赛守卫,张琴.外墙外保温抗裂砂浆抗裂性能研究[J].新型建筑材料.2006(03):61~64.
    [31]李伟,赵宏旭.外墙外保温存在的质量问题及防治[J].低温建筑技术.2007(02):140.
    [32](德)赫尔穆特,金策尔编著.外墙外抹灰:研究、经验、思考[M].王培铭,译.北京:机械工业出版社,2008,4.
    [33]H. K U nzel. Anforderungen an Au β enanstriche und Beschichtungenaus Kunstharzdispersionen[M]//(德)赫尔穆特,金策尔编著.外墙外抹灰:研究、经验、思考.王培铭,译.北京:机械工业出版社,2008,4:14.
    [34]鲍宇清,周宁,钱选青,等.外保温系统粘贴饰面砖安全性研究[J].建设科技,2008,121(8):23-28.
    [35]钱选青.如何提高外保温墙体贴饰面砖的安全性?[N].中华建筑报,2006-06-17(007).
    [36]项道阳.薄抹灰外墙外保温系统耐候性试验研究[D].北京:北京工业大学建筑工程学院,2008.
    [37]宋长友,季广其,陈丹林,等.建设部软课题/外墙保温体系防火试验方法、防火等级评价标准及建筑应用范围的技术研究介绍[J].建筑科学,2008,24(2):78~83.
    [38]宋长友,陈丹林,季广其,等.外墙外保温典型火灾案例选编[J].建筑科学,2008,24(2):12~20.
    [39]张林峰.外保温外墙保温层的粘结分析[D].天津:天津大学,2004.
    [40]刘宾,王培铭,张国防.聚合物干粉对新拌膨胀珍珠岩保温砂浆性能的影响[J].新型建筑材料,2007(2):38~52.
    [41]王培铭,李林,朱永超.纤维素醚黏度和灰砂比对新拌水泥砂浆性能的影响[C].中国建筑学会建材分会墙体保温材料及应用技术专业委员会.墙体保温与建筑节能.北京:中国电力出版社,2008:141~147.
    [42]张朝晖.ANSYS热分析教程与实例解析[M].北京:中国铁道出版社,2007:21.
    [43]徐芝纶.弹性力学(上册)(第三版)[M].北京:高等教育出版社,1990,5:166.
    [44]W. Maref, M.C. Swinton, M.K. Kumaran, M.T. Bomberg. Three-dimensional analysis of thermal resistance of exterior basement insulation systems (EIBS)[J]. Building and Environment,2001,36(4):407~419.
    [45]孔祥谦.热应力有限单元法分析[M].上海:上海交通大学出版社,1999,10:73.
    [46]中华人民共和国建设部.GB 50176-93民用建筑热工设计规范[S].北京:中国计划出版社,1993.
    [47]河南省建筑科学研究院.DBJ41/062-2005河南省居住建筑节能设计标准(寒冷地区)[S].北京:中国广播电视出版社,2005,6.
    [48]中华人民共和国建设部.GB 50003-2001砌体结构设计规范[S].北京:中国建筑工业出版社,2001.
    [49]杜平安,甘娥忠,于亚婷.有限元法:原理、建模及应用[M].北京:国防工业出版社,2004,8:4.
    [50]徐芝纶.弹性力学简明教程(第三版)[M].北京:高等教育出版社,2002,8:144~152.
    [51]中华人民共和国建设部.JGJ 144-2004外墙外保温工程技术规程[S].北京:中国建筑工业出版社.2005.
    [52]徐芝纶.弹性力学(下册)(第二版)[M].北京:人民教育出版社,1982,9:1.
    任玲玲,1983年11月17日生,2006年6月于华北水利水电学院获得工学学士学位,2007年9月于郑州大学攻读硕士学位。研究生期间参加的研究项目有:河南省重大公益科研计划项目(081100910400)、郑州市重大科技计划项目(082SGZS32079)以及郑州大学研究生科学研究基金(重点类A181)。在学期间发表的学术论文如下:
    [1]任玲玲,童丽萍.夏季极端环境下住宅墙体EPS保温体系热结构耦合分析[J].郑州大学学报(工学版),2010(31):23-26.

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