框架柱新增混凝土强度标准差分析

STANDARD DIFFERENCES OF ADDED CONCRETE STRENGTH OF FRAME COLUMNS

文中以某框架结构为案例,采用扩大截面法加固框架柱,新增混凝土强度经回弹法试验,发现标准差过大。经现场踏勘,初步分析得出存在分段浇筑施工的可能。采取对比验证方法,先抽取3根框架柱,通过分段回弹法试验,框架柱新增混凝土部分上下段回弹试验标准差有效降低,但混凝土抗压强度相差较大,同时经钻芯法验证回弹结果,证明数据可靠,进一步抽取其余加固框架柱进行验证后,得出结论,即不排除标准差过大是由于使用了不同强度等级的混凝土进行浇筑造成的,为后续类似工程项目提供借鉴与参考。

Taking a frame structure as an example,the method of enlarging section is adopted to reinforce the frame column,and the added concrete strength is tested by the rebound method.After the site investigation,the prelimi-nary analysis shows that there is a possibility of segmental pouring construction.By using the method of contrast verification,three frame columns were selected firstly,and the standard deviation of the springback test of the new concrete part of the frame columns was reduced effectively,but the compressive strength of the concrete was quite differ-ent.The rebound results are verified by the core-drilling method,which proves that the data is reliable.It is not excluding the standard deviation result from the use of the with different strength grades,which provides references for similar projects.