荆岳长江公路大桥滩桥箱梁C55混凝土早龄期强度试验研究

摘要

The strength of C55 concrete at early ages of Approach Bridge of Jing-Yue Yangtze River Highway Bridge is tested in this paper. The standard and site curing specimens are made from pumping concrete which is sam- pled from the construction site. The compressive strength, elastic modulus and rebound strength of Approach Bridge concrete at early ages are tested. The results demonstrate that the curing condition has a great influence on the con- crete strength at early age. The strength of standard curing specimens is higher than the site curing one. As the age be- comes longer, this difference in strength becomes smaller. The rebound strength detection curve is proposed based on the results of rebound strength. The rebound strength shows that the curve is sufficiently accurate. It is demonstrated that rebound method can be applied to estimate the concrete strength of bridge at early age.%文中对荆岳长江公路大桥滩桥箱梁C55混凝土早龄期强度发展规律进行了试验研究。在施工现场对泵送混凝土取样，制作标准养护和同条件养护试件，对其早龄期抗压强度、弹性模量和回弹强度进行了测试。试验结果表明：养护条件对混凝土早龄期强度的发展有较大影响，就所测试的情形而言，同养试件的强度低于标养试件，随着龄期的增长，同养试件和标养试件的强度差异有减小的趋势。此外，文中根据回弹强度结果建立了滩桥箱梁混凝土早龄期强度专用测强曲线，回弹结果表明该曲线具有较高的精度。这说明回弹法适用于桥梁工程中混凝土的早期强度评估，这对于相关的施工检测具有一定的参考意义。