双源膨胀体系对混凝土收缩性能的影响研究

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中图分类号：TU528 文献标志码：A 文章编号：1005-8249（2025）02-0025-08

DO1：10.19860/j.cnki.issn1005- 8249.2025.02.005

Abstract：Toanalyzetheexpansionefectof expansiveagentsindiferent environmentsandtheirapplicableworkingconditions， theconcrete imited expansionrateof calcium source expansion agent，magnesium source expansion agentand theircomposite dual-source expansion systemunder diferent curing temperatureand curing system conditions wasstudied.The temperature historyofthree typical workingconditionsofconcretethicknessof3Oo，8OOand130Ommwas tested，andtheconretelimited expansionrateand cracking ofthedual-source expansion systemunderthe above workingconditions were studied.Theresults show that under different curing temperatures of 2 0 ，40 and ，the 2 8 - d concrete limit expansion rate is the highest for calcium-based expansive agents，dual- source expansive agents with a calcium to magnesium ratio of 3 5 ： 6 5 ，and magnesium - based expansiveagents，respectively；under diferentcuring humidities，the higherthehumidity，thegreatertherestricted expansionrateofconcrete with expansive admixture.Underthree typical working conditions ofconcrete thicknessof 300，800

and ，the peak temperatures are 55，63 and ，respectively.The optimal expansion system for the former is a dual- source expansive agent with a calcium to magnesium ratio of 3 5 ： 6 5 ，while for the latter two，it is a magnesium-based expansiveagent，indicatingthattheoptimal expansion systemvariesunderdiferentconditions，which providesbasicdataand technical support for the selection of appropriate expansive systems under diffrent working conditions.

Key words：double-source expansion system；concrete；simulation conditions；the restrained expansion rate；crack

0 引言

混凝土作为一种广泛应用于建筑领域的材料，其性能的优劣直接影响到结构的安全性和使用寿命[1]。（剩余8877字）