木柱抗横向冲击性能研究

Study on the Lateral Impact Resistance of Wooden Columns

为研究圆木柱抗冲击性能,利用自主设计的简易落锤式试验机对圆木柱进行横向冲击试验。运用高速相机记录各试件在冲击过程中裂缝的发生、发展直至破坏的全过程,并且利用数字图像相关技术(digital image correlation method,DIC)获得试件的位移云图和冲击挠度,分析冲击高度和冲击位置等关键因素对木柱横向冲击动力响应的影响。结果表明,试件在冲击荷载作用下的整体变形表现为由受拉引起的弯曲变形,裂缝首先在试件底部产生,然后迅速在侧面并向上发展。随冲击位置由跨中向支座处靠近,对应的挠度越来越小,即跨中为最不利冲击位置,而冲击位置对冲击力峰值和冲击持续时间的影响有限。

In order to study the impact resistance of round wood columns,a simple drop hammer test machine designed by ourselves was used to conduct lateral impact tests on round wood columns.A high-speed camera was used to record the whole process of crack occurrence,development and damage of each specimen during the impact process,and the displacement cloud chart and impact deflection of the specimens were obtained by digital image correlation(DIC)technique.The effects of key factors such as impact height and impact location on the lateral impact dynamic response of the wooden column were analyzed.The test results showed that the overall deformation of the specimen under impact loading was characterised by bending deformation caused by tensile forces,with cracks first arising at the bottom of the specimen and then rapidly developing at the sides and upwards.With the impact position approaching from midspan to support,the corresponding deflection became smaller and smaller,that was,midspan was the most unfavorable impact position,and the impact location had limited effect on the peak impact force and impact duration.