考虑后续使用年限的结构可靠性鉴定方法研究

发布时间：2018-11-03 18:55

【摘要】：从我国目前以旧建筑物改造为主、国家重大基础性建设及民生建设工程穿插进行的实情出发,根据既有建筑结构的特征,对建筑结构的后续使用年限的鉴定工作进行研究。将统计数据作为科学参考,以鉴定规范中数据来源为基点展开研究。针对目前关于既有建筑结构可靠性鉴定标准之间存在的矛盾之处,结合工程人员在实际鉴定工作中存在的困惑,探究新规范对于鉴定工作产生的影响。将新旧规范更改之处进行衔接分析与理论解释,使将来鉴定工作更加系统化、科学化、经济化与合理化。基于可靠度分析理论以及荷载标准值等数据的调整,分别运用JCSS法与Monte Carlo法计算出新的目标可靠指标并依据不同可变荷载的概率统计模型计算出对应于不同设计使用年限的调整系数及数理统计参数。以最小二乘法为准则,分别采用穷举优化搜索法和极值理论求解法计算出实用设计表达式中荷载分项系数及结构重要性系数,并计算出标准值等数据调整前后的单构件的相对误差增量。从工程应用的角度出发,在荷载、抗力分项系数均按现行规范采用的情况下,计算出能同时体现不同安全等级与设计使用年限的结构重要性系数,并分析了现行规范中采用的结构重要性系数取值对应的包络范围,对今后结构设计提供参考借鉴。基于结构构件承载能力分级原则,求解出既有结构与新建结构不同后续使用年限鉴定分级系数。首先,根据既有结构与新建结构抗力数理模型的不同,归纳整理出对应的抗力统计参数；其次,根据荷载标准值调整前后的不同,求解出设计基准期下对应的鉴定分级系数；再次,依据后续使用年限调整系数与统计参数的不同,计算出现行规范条件下不同后续使用年限对应的鉴定分级系数。最后,加入考虑抗力衰减因素,对比得出鉴定分级系数的安全富余程度,为将来实际鉴定工作打下坚实的基础。
[Abstract]:Based on the fact that old buildings are mainly reformed in our country and the major national basic construction and people's livelihood construction projects are interspersed at present, according to the characteristics of the existing building structure, the appraisal work of the subsequent useful life of the building structure is studied. Taking the statistical data as the scientific reference, the research is carried out on the basis of the data sources in the identification specification. In view of the contradictions existing in the reliability evaluation standards of existing building structures and the puzzlement of engineering personnel in the actual appraisal work, this paper probes into the influence of the new code on the appraisal work. In order to make the appraisal work more systematic, scientific, economical and reasonable, the paper analyzes the changes of the new and the old norms and explains the theory. Based on reliability analysis theory and load standard value adjustment, The new target reliability index is calculated by JCSS method and Monte Carlo method, and the adjustment coefficient and mathematical statistical parameters corresponding to different design life are calculated according to the probability and statistical model of different variable loads. Based on the least square method and the exhaustive optimization search method and the extreme value theory method, the load partial coefficients and the structural importance coefficients in the practical design expressions are calculated respectively. The relative error increment of single component before and after data adjustment is calculated. From the point of view of engineering application, under the condition that the load and resistance sub-coefficients are adopted according to the current codes, the structural importance coefficients which can reflect different safety grades and design life at the same time are calculated. The envelope range corresponding to the value of the structural importance coefficient used in the current code is analyzed, which provides a reference for future structural design. Based on the principle of carrying capacity classification of structural members, the grading coefficients of existing structures and new structures with different subsequent service life are calculated. Firstly, according to the difference of the mathematical model of resistance between the existing structure and the new structure, the corresponding statistical parameters of resistance are summarized and sorted out. Secondly, according to the difference before and after adjustment of the standard value of load, the corresponding identification classification coefficient under the design reference period is solved. Thirdly, according to the difference between the adjustment coefficient and the statistical parameters, the evaluation classification coefficient corresponding to the different follow-up service life under the current standard is calculated. Finally, considering the factor of resistance attenuation, the safety surplus degree of the appraisal classification coefficient is obtained, which will lay a solid foundation for the actual appraisal work in the future.
【学位授予单位】：中国海洋大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU311.2;TU317

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