Abstract
At the main asteroid belt and Kuiper-belt region, it is commonly occurred that small bodies is disrupted into fragments by mutual collision and re-accumulated by its self-gravity. These objects are called "rubble-pile". The tensile strength of these bodies is often considered as negligible, however, they may gain the strength according to the growth of the contact points (necks)between consitituent fragments. The growth process of the neck is mainly controlled by surface diffusion and evaporative condensation. In this study, we calculate the thermal condition in these bodies, and consider the growing process of the neck, which depends on the temperature.
