结构实体混凝土强度检验与评定的试验研究

发布时间：2018-06-09 06:17

本文选题：实体混凝土强度 + 掺合料　；参考：《哈尔滨工业大学》2014年硕士论文

【摘要】：为进一步加强对建筑工程质量的监督和管理，基于“验评分离、强化验收、完善手段、过程控制”的指导原则，诸多机构开展专题研究、工程试点应用以及广泛的实践调查，本试验在哈尔滨、海南、浙江、北京等地以相同标准对此展开探索和研究。由于“标准养护试件”和实际结构构件的成型方式、尺寸大小、养护条件（温、湿度）等明显不同，“标准养护试件强度”实为一种“材料强度”，而不是“结构强度”，不能确切地代表结构实体混凝土的实际质量情况。因此，结构实体混凝土强度越来越受到人们重视，它是工程施工质量验收、鉴定加固、事故评估分析等方面重要参考指标之一。然而，工程现场对混凝土强度的检测多数仅采用单一的强度测定方法，并且采用不同方法所得出的结论不尽相同，，不能很好地适应工程质量验收标准的要求。特别是矿物掺合料混凝土强度的检测与评定研究较少，科学、可靠地评定结构实体混凝土强度对完善工程质量验收理论具有重要意义。为此，本试验对C30、C40、C50、C60四种强度等级的矿物掺合料混凝土（包括单掺粉煤灰混凝土、复掺粉煤灰和矿渣混凝土）进行研究，分析不同龄期下“标准养护试件强度”、“同条件养护试件强度”以及用“回弹法”与“钻芯法”分别获得的结构混凝土“推定强度”之间的相互关系；同时，分析了混凝土各类强度随等效龄期的增长规律。试验表明，单掺粉煤灰混凝土、复掺粉煤灰和矿渣混凝土的强度发展规律相近；在等效龄期为28d（成熟度为600oC d）时，掺合料混凝土的“同条件养护试件强度”、“结构混凝土回弹强度”和“结构混凝土取芯强度”均达不到28d的标准养护试件强度；对于掺合料混凝土，“同条件养护试件强度”可以代表“结构混凝取芯强度”来进行结构实体混凝土强度检验；还显示，直径为50mm、75mm、100mm的混凝土芯样强度基本相同。同时，掺合料混凝土的各类检测强度随龄期的变化呈对数增长趋势，并指出，为了达到规范对普通混凝土强度检验要求的标准，结构实体掺合料混凝土强度的检测龄期应适当延长；或者，在保证与普通混凝土强度检验龄期相同时，降低掺合料混凝土强度检测标准。通过把因地域差异而产生的不同试验结果综合分析，为新修订的国家标准《混凝土结构工程施工质量验收规范》(GB50204-2002)提供依据。
[Abstract]:In order to further strengthen the supervision and management of construction engineering quality, based on the guiding principles of "score separation, strengthen acceptance, perfect means, process control", many institutions carry out special research, project pilot application and extensive practical investigation. This test was carried out in Harbin, Hainan, Zhejiang, Beijing and other places with the same standards. Due to the obvious differences in the molding methods, dimensions, curing conditions (temperature, humidity) between the "standard curing specimens" and the actual structural members, "strength of standard curing specimen" is actually a kind of "material strength" rather than "structural strength", which can not represent the actual quality of concrete. Therefore, more and more attention has been paid to the strength of structural concrete, which is one of the important reference indexes in engineering construction quality acceptance, appraisal and reinforcement, accident assessment and analysis, etc. However, most of the concrete strength tests in the engineering field only use a single strength measurement method, and the conclusions obtained by different methods are different, which can not meet the requirements of engineering quality acceptance standards. Especially, the research on the testing and evaluation of concrete strength with mineral admixtures is less. It is of great significance to evaluate the strength of concrete with solid structure scientifically and reliably in order to improve the acceptance theory of engineering quality. In this paper, four kinds of mineral admixture concrete (single fly ash concrete, mixed fly ash concrete and slag concrete) with four strength grades, C30, C40, C50 and C60, are studied, and the "strength of standard curing specimen" at different ages is analyzed. The relationship between the strength of the specimen under the same condition and the constructive strength of the structural concrete obtained by the springback method and the drill core method respectively; at the same time, The increasing law of concrete strength with equivalent age is analyzed. The test results show that the strength development law of concrete with fly ash is similar to that of slag concrete, and when the equivalent age is 28 days (maturity is 600oC d), The strength of "curing specimen under the same condition", "rebound strength of structural concrete" and "coring strength of structural concrete" of admixture concrete are not up to the standard curing strength of 28 days. "strength of the specimen under the same condition" can be used to test the strength of solid concrete on behalf of "core strength of structure coagulation", and it is also shown that the strength of concrete core sample with diameter of 50mm to 75mm or 100mm is basically the same. At the same time, The testing strength of admixture concrete has a logarithmic increasing trend with age. It is pointed out that in order to meet the standard of normal concrete strength test, the testing age of structural concrete admixture strength should be extended properly. Or, at the same time as the normal concrete strength test age, reduce the admixture concrete strength detection standard. Through the comprehensive analysis of the different test results due to the regional differences, this paper provides the basis for the newly revised national standard < Code for acceptance of Construction quality of concrete structure Engineering > GB50204-2002).
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU528

【参考文献】