A STUDY ON UPGRADING METHOD OF ANCHOR-BOLTS IN EXISTING EXPOSED-TYPE STEEL COLUMN BASES

本文提出了外露式柱脚中既有锚杆的加固方法，并通过试验研究得出了以下结论。（1）加固后的锚杆在强度和变形方面有较大的提高。（2）提出了加固锚杆强度和延伸率的评定方法，该方法可以在安全范围内对加固锚杆的试验强度和延伸率进行评定。（3）现场加固的锚杆，在孔偏心小于2.5mm的情况下，其强度和延伸率与工厂加固的锚杆相当。（4）配筋锚栓的变形能力满足外露式柱脚要求的0.03rad的转动能力，基本相当于锚栓的0.03应变。

In this research upgrading method of existing anchor-bolt in the exposed-type column bases is proposed and following conclusions are obtained according to experimental studies. (1)Reinforced anchor-bolts show much upgraded performance in strength and deformation. (2)Evaluating method of strength and elongation of upgraded anchor-bolts are proposed, and these methods can estimate the experimental strength and elongation in the safe side. (3)Those anchor-bolts reinforced at the construction site have the strength and elongation as much as those reinforced in the factory, if the eccentricity of the hole is less than 2.5mm. (4)Reinforced anchor bolts have deformation capacity satisfying the rotation capacity 0.03rad demanded to exposed-type column bases, which is mostly equivalent to 0.03 strain of anchor-bolt.