Light-concentrating anti-frost anti-heave heat gathering device and subgrade thereof

A light-concentrating anti-frost anti-heave heat gathering subgrade used in seasonal frozen soil region, comprising:

• a subgrade of highway or railway;
• and
• an unpowered light-concentrating anti-frost anti-heave heat gathering device, comprising:
• a light concentrator mounted outside the subgrade;
• and
• a heat gathering tube comprising a heat absorption section, a transition section and a heat release section sequentially in communication, wherein the light concentrator is configured to focus sunlight to the heat absorption section to heat the heat absorption section, the heat absorption section is inserted inside the light concentrator for further transferring absorbed heat to the heat release section, and the heat release section is inserted inside the subgrade for heating the subgrade,
• wherein the light concentrator is mounted outside the subgrade, and the heat release section is inserted inside the subgrade,
• wherein the heat gathering tube comprises a tube body, liquid absorbing cores disposed on an inner wall of the tube body, and a phase change working medium filled inside the tube body, the phase change working medium absorbs heat and releases heat by transitioning between liquid and vapor states, and
• wherein a length direction of the transition section is parallel to a slope of the subgrade, and there is a height difference between the heat absorption section and the heat release section, so that the heat absorption section lower than the heat protection section.