Autoclaved concrete block group mold and use method thereof

The invention discloses an autoclaved concrete block group mold and a using method, the group mold comprises a bottom plate and an outer peripheral wall, an inner peripheral wall is detachably arranged in the outer peripheral wall, a certain distance is reserved between the inner peripheral wall and the outer peripheral wall so as to form an annular area in a clamping mode, a ventilation heating pipe ring is further arranged in the annular area, an annular rectangular center wall is arranged in the inner peripheral wall, and the annular rectangular center wall is arranged in the annular heating pipe ring. An annular pouring area is formed between the inner surrounding wall and the center wall in a clamped mode, the length and the width of the center wall can be changed, the four outer side wall faces are smooth faces all the time before and after the size changes, the bottom of the center wall is detachably and fixedly connected to the upper end face of the bottom plate, and the bottom of the center wall is a