From the point of the structure engineering, the shrinkage strains of 28 concrete specimens are measured on series 360 days. The multi-coefficient formula of shrinkage strains for concrete is gained the age, the compressive strength, the environmental condition and the specimen dimension are all analyzed in detail. In the formula, the 28-day compressive strength for concrete is regarded as a comprehensive variable,the shrinkage strains are changed continually with the compressive strength. The changes of relative humidity are considered,and the changes of temperature are considered firstly. A comparison between the suggested formula, ACI209 formula, literature [5] formula is conducted. The result shows that the suggested shrinkage strains are closer to the experimental shrinkage strains,and the suggested formula is also suit for the shrinkage experimental shrinkage strains of Luoxi Bridge.%从工程结构的视角,对28个商品混凝土标准收缩构件的收缩变形进行了360 d的试验及理论分析研究,提出了商品混凝土收缩变形的多系数估算公式.估算公式中考虑了龄期、混凝土强度、环境温湿度及构件尺寸对收缩的影响.将混凝土28 d立方体抗压强度作为一综合变量,商品混凝土的收缩随抗压强度呈连续变化；既考虑了常规的相对湿度对收缩的影响,也首次考虑了环境温度对收缩的影响.将本文建议公式与ACI 209公式、文献[5]公式各龄期自由收缩变形计算值与相应龄期的实测值进行了比较.结果表明,本文建议的计算公式与实测结果相接近.此外,建议公式也与广东省洛溪大桥混凝土的收缩试验结果吻合较好,工程适用性强.
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