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

本文提出了对暴露式柱基础现有锚杆进行升级改造的方法，并通过试验研究得出以下结论：(1)加固后锚杆在强度和变形性能上均有较大提升。(2)提出了升级锚杆强度和伸长率的评价方法，该方法可用于安全侧试验强度和伸长率的估算。(3)在施工现场加固的锚固螺栓，如果孔的偏心小于2.5mm，其强度和伸长率与工厂加固的锚固螺栓相同。(4)加筋式锚杆的变形能力满足露露式柱底座转动能力0.03rad的要求，多相当于锚杆应变0.03。

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.