The unloadingcurve normally falls below the loading curve to form a hysteresis loop .
卸载曲线通常都落在加载曲线之下,形成一个滞后回线。
2
There are three kinds of methods of concrete column strengthened with prestressed. The concept of unloadingcurve for the strengthening method with prestressing is introduced.
Spindle static stiffness unloading is more than that of loading. The elastic deformation of spindle system resumes stagnantly when unloading. So the loading curve and unloadingcurve are not closed.