The invention relates to a combined hollow box body used for a cast-in-place energy-saving hollow floor
system, which comprises a bottom surface, an arc surface, a hole wall, a side surface and a top surface, wherein a concave closed hole is remained in the side surface and got through before
casting to enable a connecting short
pipe to pass through to form a mutually connected through
heat energy air supplying channel, a groove for laying a heating
pipe is remained on the top surface, and the groove and the
heat energy air supplying channel form a floor
system energy supplying
system; the bottom surface and the side surface of the box body form the arc surface, the
arc length of the arc surface is more than 70mm, the length of the arc
radius is more than 45mm, and the arc surface is used for preventing a jointing surface of the box body and a rib beam from
cracking and the box body from dropping under the conditions of earthquake and the like; and the upper end of the hole wall and the top surface form a
casting hole, concrete is poured in the
casting hole to be compounded with an iron wire remained on the bottom surface during the cast-in-place, thus the
upper wing edge of the floor system can be connected with the bottom surface of the box body, and the stress structure of the floor system is improved. The floor system adopting the hollow box body has the advantages of light weight, large
hardness, reasonable structure, crack control and
earthquake resistance; and the problem of heating can be solved by adopting a manner of transmitting the
heat energy by the box body.