建筑旧桩的桩身材料耐久性能试验研究

Experimental study on the durability of pile materials for old building piles

对旧桩进行桩身材料耐久性能检测是评估旧桩承载性能的重要方面,也是旧桩再利用的前提。依托上海曹家渡花鸟市场改造工程,对桩身混凝土开展了碳化深度、抗压强度和氯离子含量试验,并检测了混凝土中钢筋的锈蚀程度和抗拉性能。结果表明:随着距桩顶距离的增加,桩身混凝土的碳化深度和氯离子含量均逐渐减小,抗压强度逐渐增大;随着距桩顶距离的增加,混凝土中钢筋的直径、屈服强度和极限抗拉强度均略有减小,但仍满足HRB335级钢筋的强度要求;该工程旧桩满足原位再利用要求。

Testing the durability of pile materials for old piles is an important aspect of evaluating the bearing capacity of old piles and a prerequisite for their reuse.Based on the renovation project of the Caojiadu Bird and Flower Market in Shanghai,the carbonation depth,compressive strength,and chloride ion content tests of the pile concrete were conducted,and the corrosion degree and tensile performance of the steel bars in the concrete were tested.The results show that as the distance from the pile top increases,the carbonation depth and chloride ion content of the pile concrete gradually decrease,and the compressive strength gradually increases.As the distance from the pile top increases,the diameter,yield strength,and ultimate tensile strength of the steel bars in the concrete slightly decrease,but still meet the strength requirements of HRB335 grade steel bars.The old piles in this project meet the requirements for in-situ reuse.