土木建筑与环境工程
土木建築與環境工程
토목건축여배경공정
Journal of Chongqing Jianzhu University
2015年
5期
41-47
,共7页
蠕变模型%约束钢梁%抗火性能%钢结构
蠕變模型%約束鋼樑%抗火性能%鋼結構
연변모형%약속강량%항화성능%강결구
creep model%restrained beam%fire resistance%steel structure
钢材在高温和荷载作用下产生明显蠕变变形,影响火灾中结构的变形和受力性能。现有的蠕变模型较多,但没有一个广泛适用的蠕变模型。不同的蠕变模型对钢结构抗火分析结果有很大影响。为了量化蠕变模型对约束钢梁抗火性能分析的影响,对5种常用的蠕变模型进行了对比分析。采用编写的约束钢梁计算程序,分别计算5种蠕变模型下约束钢梁的抗火性能并与试验数据进行对比。结果表明,采用 Norton 蠕变模型的计算结果与试验数据吻合最好。最后对影响约束钢梁抗火性能参数进行了研究,研究发现,Harmathy 蠕变模型对约束梁抗火性能分析结果影响最大;不同蠕变模型对不同荷载比、约束刚度下的约束钢梁抗火性能影响程度均不同。
鋼材在高溫和荷載作用下產生明顯蠕變變形,影響火災中結構的變形和受力性能。現有的蠕變模型較多,但沒有一箇廣汎適用的蠕變模型。不同的蠕變模型對鋼結構抗火分析結果有很大影響。為瞭量化蠕變模型對約束鋼樑抗火性能分析的影響,對5種常用的蠕變模型進行瞭對比分析。採用編寫的約束鋼樑計算程序,分彆計算5種蠕變模型下約束鋼樑的抗火性能併與試驗數據進行對比。結果錶明,採用 Norton 蠕變模型的計算結果與試驗數據吻閤最好。最後對影響約束鋼樑抗火性能參數進行瞭研究,研究髮現,Harmathy 蠕變模型對約束樑抗火性能分析結果影響最大;不同蠕變模型對不同荷載比、約束剛度下的約束鋼樑抗火性能影響程度均不同。
강재재고온화하재작용하산생명현연변변형,영향화재중결구적변형화수력성능。현유적연변모형교다,단몰유일개엄범괄용적연변모형。불동적연변모형대강결구항화분석결과유흔대영향。위료양화연변모형대약속강량항화성능분석적영향,대5충상용적연변모형진행료대비분석。채용편사적약속강량계산정서,분별계산5충연변모형하약속강량적항화성능병여시험수거진행대비。결과표명,채용 Norton 연변모형적계산결과여시험수거문합최호。최후대영향약속강량항화성능삼수진행료연구,연구발현,Harmathy 연변모형대약속량항화성능분석결과영향최대;불동연변모형대불동하재비、약속강도하적약속강량항화성능영향정도균불동。
Significant creep deformation occurs in steel subjected to elevated temperatures and loading,and thus affects the deformation and load capacity of steel Structures in fire.Currently there are many creep models,which are not widely suitable.Significant effect on fire resistance analysis of steel beam can be observed using different creep models.In order to quantity this effect,comparison was made to analyze five kinds of creep model.Fire resistance of restrained beam under five creep models was analyzed using computer program and the results were compared with test data.Norton creep model revealed best agreement with test data.Finally,parametric study was conducted on the parameters affecting the fire resistance of restrained steel beams.It is showed that Harmathy creep model had a greatest effect on fire response of restrained steel beams.The degree of creep influence to fire resistance of restrained steel beams for different creep models under different load ratio and restraint were different.