Study of the Time Characteristics for Stress Wave Propagating in Wood

When knocking different location source sensors,tested stress wave propagating time in the wooden disc sample which is intact,and in same sample drilled certain diameter hole,based definite sensor arrangement way and quantity.under the condition of identical source sensor location,testing stress wave propagation time-goal sensor location curve,respectively in the hole sample and the intact.Analyzed the characteristic of stress wave propagation time change in the hole timber internal comparatively,evaluated timber internal hole qualitative.