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摘要：光伏建筑一體化是现阶段最重要的新兴产业之一，光伏建筑一体化受到各国的高度重视，光伏建筑也越来越多，但就国内外各规范与标准中并没有涉及光伏荷载的问题。本文就是采用概率极限状态设计方法，利用统计分析计算所得数据，确定按现有荷载规范对屋面设有光伏的建筑结构进行设计时，是否能满足可靠性要求。
关键词：光伏建筑一体化；可靠指标；荷载；分项系数
Abstract: In this stage, BIPV is one of the most important emerging industries, BIPV highly valued by all countries, photovoltaic building more and more, but on the domestic and international norms and standards and did not involve the PV load problem. This paper is the use of probabilistic limit state design method, using statistical analysis of the data, to determine the load according to the existing norms for a photovoltaic roof when designing building structures, whether it can meet the reliability requirements.
Keywords: BIPV; reliable indicator; loading; partial factor
But in the domesticAbstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements.
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements.
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements.
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements
中图分类号：TU973+.33 文献标识码：A 文章编号：
光伏的承载体很多有建筑屋面、阳台、天井、墙面、廊棚等，最常见的承载体为屋面，本文讨论光伏组件在平屋面和坡屋面的各种安装工艺，并计算对应的荷载值。将屋面光伏活荷载分为持续性活荷载与临时性活荷载，将局部荷载转化为均布荷载。应用数理统计分析方法确定荷载设计基准期标准值，再根据概率极限状态计算原则，分别计算单独考虑恒载与屋面光伏活荷载组合和综合考虑四种荷载效应组合情况的最优荷载分项系数。以上两种情况确定的分项系数只是根据现有掌握数据计算所得，为了保证通用性，本文只是将计算所得分项系数与《建筑结构荷载规范GB50009-2001（2006年）》【1】中分项系数比较并判断按《荷载规范》中分项系数（G=1.2,Q=1.4),进行设计是否能满足可靠性要求。
1 屋面光伏荷载统计
屋面光伏荷载按其随时间变异的特点，可分为持续性与临时性，其中持续性荷载主要包括光伏组件荷载、支架、混凝土墩等。屋面光伏临时性活荷载主要包括人员荷载。按照屋面光伏不同的安装工艺分别计算持续性活荷载，并根据荷载规范将局部荷载转化为均布荷载。本文施工人员临时性活荷载，参照论文《建筑施工期活荷载统计分析及荷载效应影响面分析》【2】中对10个工程项目施工时期的人员荷载的统计数据进行分析，采用房间面积平均荷载来代替等效均布荷载。
本文屋面光伏各安装工艺主要参照图集10J908-5《建筑太阳能光伏安装系统设计与安装》【3】, 为了结果具有普遍通用性论文選用现在设计中常采用架空式瓦屋面光伏组件安装、嵌入式瓦屋面光伏组件安装、平屋面光伏组件安装、特殊支架光伏组件安装这四种工艺进行统计分析。
通过对各种不同的安装工艺进行统计，并将局部荷载转为均布荷载后，对所得数据进行K-S检验【4】确定持续性荷载与临时性荷载均满足极值I分布，确定任意时刻屋面光伏持续性活荷载均值为0.2883 kN/m2，标准差为0.1881 kN/m2；任意时刻人员荷载满足极值I分布均值为0.0402 kN/m2，标准差为0.0071 kN/m2。
2 荷载参数统计分析
（1）屋面光伏持续性活荷载统计参数分析
屋面光伏组件一般寿命为10~25年，本文按10年后重新安装，安装需要时间较短出现的概率约等于1，设计基准期T为50年，在设计基准期内荷载发生5次变化即r=5，已知任意时点光伏持久活荷载满足极值I分布均值为0.2883 kN/m2，标准差为0.1881 kN/m2, 根据平稳二项随机过程模型【5】确定设计基准期内荷载最大值的概率分布。
;
;
均值 LiT=0.4397+0.5772αT=0.5244kN/m2；
标准差 LiT=0.1881kN/m2；
变异系数LiT=0.3587
（2）临时性活荷载统计参数分析
统计得任意时刻人员荷载满足极值I分布均值为0.0402 kN/m2，标准差为0.0071 kN/m2。
;
均值 LiT=0.0459+0.5772αT=0.0491kN/m2；
标准差 LiT=0.0071kN/m2；
变异系数LiT=0.1446
由前面统计分析结果和Turkstra组合规则【6】，将屋面光伏持续性活荷载与临时性活荷载组合，可得出在设计基准期内光伏屋面活荷载的统计参数为：
=0.5646kN/m2;
=0.1882 kN/m2;
0.3333
利用matlab软件确定设计基准期屋面光伏活荷载最大值概率分布的0.05分位点对应的荷载值为屋面光伏活荷载的标准值其值为0.7711kN/m2。
3分项系数确定
（1）在各项标准值确定的前提下，要选取一组分项系数，使按极限状态设计表达式设计的各种构件多具有的可靠指标，与规定的可靠指标之间的误差要最小。具体要考虑一下几个方面：
①确定荷载及抗力的各参数，屋面光伏活荷载各参数通过上述计算已经确定，结构构件抗力各参数可以参考结构构件抗力统计参数表。
②考虑荷载组合情况和确定可变荷载与永久荷载的比值范围。论文分两种情况进行分析，第一种为屋面光伏活荷载+恒载单独组合，第二种为综合考虑四种荷载组合（恒载+屋面光伏活荷载、恒载+办公楼楼面活荷载、恒载+住宅楼楼面活荷载、恒载+风荷载），活荷载的各参数见表1。通常情况下由综合考虑所得的分项系数为最后确定的分项系数值，但当考虑单独组合情况所得系数远大于综合考虑各种可能出现的组合所得分项系数，这时就需要在综合考虑各组合情况所得分项系数前乘以相应的扩大系数以满足可靠性要求【7】。所以本文对这两种情况都做了分析。
③选择有代表性的构件，规定可靠指标。屋面光伏常安装于钢结构、薄钢、钢筋混凝土结构上，所以本文选择了相关的9种代表性构件，按规范要求结构安全等级，对应不同的可靠指标T详见表2。
表1各种荷载的统计参数
表2 各结构构件对应可靠指标
（2）恒载与屋面光伏活荷载单独组合时，抗力差值I的确定
抗力差值最小的一组荷载分项系数为最优分项系数，表达式如下：
恒载+屋面光伏活荷载组合，I值计算结果 如表3所示。
表3 恒载与屋面光伏活荷载组合时，I值
恒载与屋面光伏活荷载组合情况下，单独考虑所得的荷载分项系数G=1.1，Q=1.4低于荷载规范所得的荷载分项系数，因而按荷载规范取用G=1.2，Q=1.4，进行计算时能保证结构达到目标可靠指标。
（3）综合考虑四种荷载效应组合时，抗力差值I的确定
综合考虑四种荷载效应组合，I值计算结果 如表4所示。
表4 综合考虑四种荷载效应组合后I值
综合考虑恒载+屋面光伏活荷载组合、恒载+办公楼楼面活荷载、恒载+住宅楼楼面活荷载和恒载+风荷载情况下，所得的荷载分项系数G=1.1，Q=1.1。
4結论
由于对屋面结构进行设计时，规范中屋面活荷载中已经包括了施工人员临时性活荷载，在设计时应扣除光伏屋面施工人员临时性活荷载，利用matlab软件确定设计基准期屋面光伏活荷载最大值概率分布的0.05分位点对应的荷载值为屋面光伏活荷载的标准值其值为0.5396kN/m2，为方便计算直接取为0.54kN/m2。即不上人的光伏屋面活荷载取其1.04kN/m2，上人的光伏屋面活荷载为2.54kN/m2。
恒载与屋面光伏活荷载单独组合情况下及恒载与4种活荷载综合考虑情况下所得的分项系数均小于与规范中规定的荷载分项系数（G=1.2，Q=1.4），即按该分项系数进行设计能满足可靠性要求。
5 参考文献
[1]中华人民共和国国家规范.建筑结构荷载规范GB50009-2001（2006年）[S].北京：中国建筑工业出版社,2002.
[2]胡杭.建筑施工期活荷载统计分析及荷载效应影响面分析 [D].北京：北京交通大学硕士论文,2009
[3]建筑太阳能光伏系统设计与安装(10J908-5)[S].北京：中国计划出版社，2010
[4]胡国雷，何铭，孔告化.概率论与随机过程[M].北京：人民邮电出版社，2011.9
[5]黄兴棣，工程结构可靠性设计[M].北京：人民交通出版社，1989
[6]P.索夫特-克里斯坦森 M.J.贝克.结构可靠性理论及其应用[M],1988年
[7]龚治国，候建国等，吴春秋.现行规范中荷载分项系数的比较及修定建议[R].武汉化工学院学报.第23卷 第4期,2001
关键词：光伏建筑一体化；可靠指标；荷载；分项系数
Abstract: In this stage, BIPV is one of the most important emerging industries, BIPV highly valued by all countries, photovoltaic building more and more, but on the domestic and international norms and standards and did not involve the PV load problem. This paper is the use of probabilistic limit state design method, using statistical analysis of the data, to determine the load according to the existing norms for a photovoltaic roof when designing building structures, whether it can meet the reliability requirements.
Keywords: BIPV; reliable indicator; loading; partial factor
But in the domesticAbstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements.
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements.
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements.
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements
Abstract: photovoltaic building integrated is one of the most important emerging industries, at present stage photovoltaic building integrated attaches great importance to by national photovoltaic building more and more, but on domestic and foreign various norms and standards are not covered in the photovoltaic (pv) load. The probability limit state design method is the use of statistical analysis is used to calculate the data, determine the current load specification of roofing is equipped with photovoltaic building structural design, whether it can meet the reliability requirements
中图分类号：TU973+.33 文献标识码：A 文章编号：
光伏的承载体很多有建筑屋面、阳台、天井、墙面、廊棚等，最常见的承载体为屋面，本文讨论光伏组件在平屋面和坡屋面的各种安装工艺，并计算对应的荷载值。将屋面光伏活荷载分为持续性活荷载与临时性活荷载，将局部荷载转化为均布荷载。应用数理统计分析方法确定荷载设计基准期标准值，再根据概率极限状态计算原则，分别计算单独考虑恒载与屋面光伏活荷载组合和综合考虑四种荷载效应组合情况的最优荷载分项系数。以上两种情况确定的分项系数只是根据现有掌握数据计算所得，为了保证通用性，本文只是将计算所得分项系数与《建筑结构荷载规范GB50009-2001（2006年）》【1】中分项系数比较并判断按《荷载规范》中分项系数（G=1.2,Q=1.4),进行设计是否能满足可靠性要求。
1 屋面光伏荷载统计
屋面光伏荷载按其随时间变异的特点，可分为持续性与临时性，其中持续性荷载主要包括光伏组件荷载、支架、混凝土墩等。屋面光伏临时性活荷载主要包括人员荷载。按照屋面光伏不同的安装工艺分别计算持续性活荷载，并根据荷载规范将局部荷载转化为均布荷载。本文施工人员临时性活荷载，参照论文《建筑施工期活荷载统计分析及荷载效应影响面分析》【2】中对10个工程项目施工时期的人员荷载的统计数据进行分析，采用房间面积平均荷载来代替等效均布荷载。
本文屋面光伏各安装工艺主要参照图集10J908-5《建筑太阳能光伏安装系统设计与安装》【3】, 为了结果具有普遍通用性论文選用现在设计中常采用架空式瓦屋面光伏组件安装、嵌入式瓦屋面光伏组件安装、平屋面光伏组件安装、特殊支架光伏组件安装这四种工艺进行统计分析。
通过对各种不同的安装工艺进行统计，并将局部荷载转为均布荷载后，对所得数据进行K-S检验【4】确定持续性荷载与临时性荷载均满足极值I分布，确定任意时刻屋面光伏持续性活荷载均值为0.2883 kN/m2，标准差为0.1881 kN/m2；任意时刻人员荷载满足极值I分布均值为0.0402 kN/m2，标准差为0.0071 kN/m2。
2 荷载参数统计分析
（1）屋面光伏持续性活荷载统计参数分析
屋面光伏组件一般寿命为10~25年，本文按10年后重新安装，安装需要时间较短出现的概率约等于1，设计基准期T为50年，在设计基准期内荷载发生5次变化即r=5，已知任意时点光伏持久活荷载满足极值I分布均值为0.2883 kN/m2，标准差为0.1881 kN/m2, 根据平稳二项随机过程模型【5】确定设计基准期内荷载最大值的概率分布。
;
;
均值 LiT=0.4397+0.5772αT=0.5244kN/m2；
标准差 LiT=0.1881kN/m2；
变异系数LiT=0.3587
（2）临时性活荷载统计参数分析
统计得任意时刻人员荷载满足极值I分布均值为0.0402 kN/m2，标准差为0.0071 kN/m2。
;
均值 LiT=0.0459+0.5772αT=0.0491kN/m2；
标准差 LiT=0.0071kN/m2；
变异系数LiT=0.1446
由前面统计分析结果和Turkstra组合规则【6】，将屋面光伏持续性活荷载与临时性活荷载组合，可得出在设计基准期内光伏屋面活荷载的统计参数为：
=0.5646kN/m2;
=0.1882 kN/m2;
0.3333
利用matlab软件确定设计基准期屋面光伏活荷载最大值概率分布的0.05分位点对应的荷载值为屋面光伏活荷载的标准值其值为0.7711kN/m2。
3分项系数确定
（1）在各项标准值确定的前提下，要选取一组分项系数，使按极限状态设计表达式设计的各种构件多具有的可靠指标，与规定的可靠指标之间的误差要最小。具体要考虑一下几个方面：
①确定荷载及抗力的各参数，屋面光伏活荷载各参数通过上述计算已经确定，结构构件抗力各参数可以参考结构构件抗力统计参数表。
②考虑荷载组合情况和确定可变荷载与永久荷载的比值范围。论文分两种情况进行分析，第一种为屋面光伏活荷载+恒载单独组合，第二种为综合考虑四种荷载组合（恒载+屋面光伏活荷载、恒载+办公楼楼面活荷载、恒载+住宅楼楼面活荷载、恒载+风荷载），活荷载的各参数见表1。通常情况下由综合考虑所得的分项系数为最后确定的分项系数值，但当考虑单独组合情况所得系数远大于综合考虑各种可能出现的组合所得分项系数，这时就需要在综合考虑各组合情况所得分项系数前乘以相应的扩大系数以满足可靠性要求【7】。所以本文对这两种情况都做了分析。
③选择有代表性的构件，规定可靠指标。屋面光伏常安装于钢结构、薄钢、钢筋混凝土结构上，所以本文选择了相关的9种代表性构件，按规范要求结构安全等级，对应不同的可靠指标T详见表2。
表1各种荷载的统计参数
表2 各结构构件对应可靠指标
（2）恒载与屋面光伏活荷载单独组合时，抗力差值I的确定
抗力差值最小的一组荷载分项系数为最优分项系数，表达式如下：
恒载+屋面光伏活荷载组合，I值计算结果 如表3所示。
表3 恒载与屋面光伏活荷载组合时，I值
恒载与屋面光伏活荷载组合情况下，单独考虑所得的荷载分项系数G=1.1，Q=1.4低于荷载规范所得的荷载分项系数，因而按荷载规范取用G=1.2，Q=1.4，进行计算时能保证结构达到目标可靠指标。
（3）综合考虑四种荷载效应组合时，抗力差值I的确定
综合考虑四种荷载效应组合，I值计算结果 如表4所示。
表4 综合考虑四种荷载效应组合后I值
综合考虑恒载+屋面光伏活荷载组合、恒载+办公楼楼面活荷载、恒载+住宅楼楼面活荷载和恒载+风荷载情况下，所得的荷载分项系数G=1.1，Q=1.1。
4結论
由于对屋面结构进行设计时，规范中屋面活荷载中已经包括了施工人员临时性活荷载，在设计时应扣除光伏屋面施工人员临时性活荷载，利用matlab软件确定设计基准期屋面光伏活荷载最大值概率分布的0.05分位点对应的荷载值为屋面光伏活荷载的标准值其值为0.5396kN/m2，为方便计算直接取为0.54kN/m2。即不上人的光伏屋面活荷载取其1.04kN/m2，上人的光伏屋面活荷载为2.54kN/m2。
恒载与屋面光伏活荷载单独组合情况下及恒载与4种活荷载综合考虑情况下所得的分项系数均小于与规范中规定的荷载分项系数（G=1.2，Q=1.4），即按该分项系数进行设计能满足可靠性要求。
5 参考文献
[1]中华人民共和国国家规范.建筑结构荷载规范GB50009-2001（2006年）[S].北京：中国建筑工业出版社,2002.
[2]胡杭.建筑施工期活荷载统计分析及荷载效应影响面分析 [D].北京：北京交通大学硕士论文,2009
[3]建筑太阳能光伏系统设计与安装(10J908-5)[S].北京：中国计划出版社，2010
[4]胡国雷，何铭，孔告化.概率论与随机过程[M].北京：人民邮电出版社，2011.9
[5]黄兴棣，工程结构可靠性设计[M].北京：人民交通出版社，1989
[6]P.索夫特-克里斯坦森 M.J.贝克.结构可靠性理论及其应用[M],1988年
[7]龚治国，候建国等，吴春秋.现行规范中荷载分项系数的比较及修定建议[R].武汉化工学院学报.第23卷 第4期,2001