基于静力荷载实验的城市树木抗风修剪比例研究

Research on Wind-resistant Pruning Ratios for Urban Trees Based on Static Load Tests

摘要:

我国东南沿海地区台风及强对流天气多发，近年来不少城市常发生强风导致树木倒伏的事故。为探究城市树木抗风性与其修剪比例的关系，聚焦于广州市行道树的常见树形卵形和塔形，选择卵形树种中国无忧花 Saraca dives、人面子 Dracontomelon duperreanum，以及塔形树种小叶榄仁 Terminalia neotaliala、木棉 Bombax ceiba 为研究对象，基于静力荷载实验，开展树木形态稳定性分析及不同修剪次数下拉力与角度相关性研究，以确定城市树木的最佳抗风修剪比例。结果表明：树越高、树冠越不对称，树木的稳定性越低；树木的修剪比例显著影响树木抗风能力，卵形和塔形树木的城市树木最佳抗风修剪比例为11％ ~25％。

Abstract:

In China's southeastern coastal areas, typhoons and severe convective weather are frequent, and in recent years, many cities have experienced accidents of tree failure caused by strong winds. To investigate the relationship between urban tree wind resistance and pruning ratio, this study focuses on the common tree shapes found among Guangzhou's street trees—the oval and pyramidal shapes—and selects the oval-shaped species Saraca dives and Dracontomelon duperreanum, as well as the pyramidal-shaped species Terminalia neotaliala and Bombax ceiba, as the subjects. Based on static load tests, an analysis of tree morphological stability and a study on the correlation between pulling force and angle under different pruning frequencies are conducted, so as to determine the optimal wind-resistant pruning ratio for urban trees. The results indicate that taller trees and more asymmetrical crowns exhibit lower stability. The pruning ratio significantly affects tree wind resistance, and the optimal pruning ratios for both oval-shaped and pyramidal urban trees fall within the range of 11%~25%.