现场浇筑大坝混凝土断裂参数与等效成熟度关系研究  

Relationship between fracture parameters with an equivalent maturity of site-casting dam concrete

作　　者：管俊峰[1,2,3] 李庆斌[2] 吴智敏[3] 赵顺波[1] 

机构地区：[1]华北水利水电大学土木与交通学院,河南郑州450011 [2]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [3]大连理工大学海岸与近海工程国家重点实验室,辽宁大连116024

出　　处：《水利学报》2015年第8期951-959,共9页Journal of Hydraulic Engineering

基　　金：国家自然科学基金重点项目(51339003);国家自然科学基金项目(51209094);海岸和近海工程国家重点实验室基金(LP1211);河南省高等学校青年骨干教师资助计划(2013GGJS-084)

摘　　要：不同时段浇筑的大坝混凝土处于不同的外界环境条件,即对应于不同的温度、龄期及养护条件。因此,确定现场浇筑大坝混凝土的真实断裂特性,须考虑外界环境条件不同对其的影响。本文提出"等效成熟度"的概念,研究确定现场浇筑大坝混凝土的断裂参数与等效成熟度的关系。结合大坝施工现场浇筑的不同龄期试件的断裂试验成果,分析了等效温度对大坝混凝土"断裂韧度-等效成熟度"关系的影响规律,进而给出了大坝混凝土"断裂韧度-等效成熟度"的合理关系式。结果表明,采用大坝混凝土28 d龄期内的平均气温作为等效温度,可得到较好的"断裂韧度-等效成熟度"相关关系。研究成果可为求取大坝混凝土任意时刻的真实断裂参数提供依据。Dam concrete cast in different time is affected by different external conditions, thus, has different temperature, age and curing conditions. Therefore, the true fracture properties of dam concrete can be obtained, in which the effect of external conditions should be considered. In this paper, the concept of ＂equivalent maturity＇was proposed to determine the relationship between the fracture parameters with an equivalent maturity of site-casting dam concrete. Combined with the experimental fracture parameters of wedge-splitting specimens at different age obtained from a dam construction site, the effect of equivalent temperature on the reasonable relationship between the fracture parameters with an equivalent maturity was analyzed, and the relationship on ＂Fracture toughness-equivalent maturity relation＂ of site-casting dam concrete was obtained. The best results were achieved by taking the average temperature during age of 28 days as the equivalent temperature in calculating the equivalent maturity. The results can provide a scientific basis for obtaining the true fracture parameters of dam concrete at any time.

关 键 词：大坝混凝土 现场浇筑 断裂参数 试件龄期 外界环境温度 等效成熟度 等效温度 

分 类 号：TV313[水利工程—水工结构工程] TV41