目的 以水曲柳为研究对象，研究高应变率压缩载荷作用下水曲柳试件的解离特征和能量耗散机制。方法 利用压缩加载试验分析应变率、加载方向对受载水曲柳的形态特征影响和动力学特性，并利用弹塑性基本原理分析其受压解离的能量耗散机制。结果 解离后径向加载试件主要呈火柴棍状，弦向加载试件主要呈片状，轴向加载试件主要呈不规则块状，试件的解离程度随应变率的增大而增大;当应变率在400~1 000 s⁻¹时，水曲柳试件的应力-应变曲线由弹性阶段和屈服后弱线性强化阶段两部分组成;水曲柳试件的屈服强度随应变率的增大而增大，当应变率从400 s⁻¹增加到1 000 s⁻¹时，径向、弦向和轴向加载试件的屈服强度分别增加了0.45倍、1.34倍和0.71倍;木材原料沿径、弦向解离时主要依靠木材细胞的压缩变形来耗散能量，沿轴向解离时主要依靠木材细胞纵向结构的弯曲来耗散能量。结论 弦向最易解离，轴向最难解离;水曲柳是一种应变率敏感材料;木材原料径、弦向解离主要依靠压缩变形来耗散能量，轴向解离主要依靠弯曲变形来耗散能量，木材原料解离能够耗散能量的多少主要受加载方向、木材细胞的结构尺寸和力学性能的影响。

The work aims to study the dissociation characteristics and energy dissipation mechanism of fraxinus mandshurica specimens under high strain rate compression loading with the fraxinus mandshurica as the research object. The effect of strain rate and loading direction on the morphological and dynamic characteristics of the loaded fraxinus mandshurica was analyzed by compression loading experiments, and the energy dissipation mechanism of its compression dissociation was analyzed by the basic principles of elastic-plasticity. After dissociation, the radial loaded specimens were mainly in the shape of matchstick, the tangential loaded specimens were mainly in the shape of chips, and the axial loaded specimens were mainly in the shape of irregular blocks. The dissociation degree of the specimens increased with the increase of strain rate. When the strain rate was in the range of 400 s–1 to 1 000 s–1, stress-strain curve of fraxinus mandshurica specimens consisted of two parts:the elastic stage and the weakly linear strengthening stage after yielding. The yield strength of fraxinus mandshurica specimens increased with the increase of strain rate. When the strain rate increased from 400 s–1 to 1 000 s–1, the yield strength of specimens subject to radial, tangential and axial loading increased by 0.45 times, 1.34 times and 0.71 times, respectively. When wood raw materials dissociated along the radial and tangential directions, they mainly depended on the compression deformation of wood cells to dissipate energy, and when dissociating along the axial direction, they mainly depended on the bending of the longitudinal structure of wood cells to dissipate energy. The tangential-loading specimens are the most easy to dissociate and the axial-loading specimens are the most hard to dissociate. Fraxinus mandshurica is a material sensitive to strain rate. When wood raw materials dissociate along the radial and tangential directions, they mainly depend on the compression deformation to dissipate energy, and when dissociating along the axial direction, they mainly depend on the bending deformation to dissipate energy. The amount of energy that wood raw material dissociation can dissipate is mainly affected by the loading direction, structural size of wood cells, and mechanical properties.