This paper presents development of temperature-induced transient creep strain in different types of concrete. To measure creep strain, concrete specimens were subjected to combined effects of heating and mechanical loading in the temperature range between 20 °C and 800 °C. The test variables included temperature, load level, rate of heating, strength of concrete and presence of fibers in concrete. Data from these tests indicate that transient creep strain constitutes a significant portion of total strain. Data also affirm that temperature range and stress level have significant influence on the magnitude of transient creep strain, specially at temperatures above 500 °C and stress levels of 40% or more. However, rate of heating and presence of fibers in concrete have only a moderate influence on the generated transient creep. Presence of steel fibers in normal strength concrete slightly reduce the extent of transient creep strain, while the addition of polypropylene fibers to high strength concrete leads to higher transient creep strain. Finally, data generated in tests on transient creep strain is utilized to propose temperature and stress dependent creep strain relations for different types of concrete.

本文介绍了不同类型混凝土中温度引起的瞬态蠕变应变的发展。为了测量蠕变应变，在20°C至800°C的温度范围内，混凝土试样受到加热和机械载荷的共同作用。测试变量包括温度，负载水平，加热速率，混凝土强度以及混凝土中纤维的存在。这些测试的数据表明，瞬时蠕变应变占总应变的很大一部分。数据还证实，温度范围和应力水平对瞬态蠕变应变的幅度有重大影响，特别是在温度高于500°C且应力水平为40％或更高时。但是，加热速率和混凝土中纤维的存在对所产生的瞬态蠕变仅具有中等影响。在正常强度的混凝土中存在钢纤维会稍微降低瞬态蠕变应变的程度，而在高强度混凝土中添加聚丙烯纤维会导致较高的瞬态蠕变应变。最后，利用在瞬态蠕变应变测试中生成的数据，针对不同类型的混凝土提出了温度和应力相关的蠕变应变关系。