A heavy-cast and light-cast building and construction method of a shell
assembly system, comprising a hollow steel section column I, a pull-out wall shell net, a steel truss beam and a prestressed
floor slab, wherein a plurality of the hollow steel section columns I are connected end to end, and the hollow steel section column I located at the floor elevation is connected to the steel truss beam, an
insulation layer is provided on the outer side of the steel truss beam, and a prestressed
floor slab is connected to the inner side of the steel truss beam, and a pull-out wall shell net is provided between the outer sides of two adjacent hollow steel section columns I, and the height of the pull-out wall shell net is consistent with the height of the hollow steel section column, the
insulation layer is butted with the pull-out wall shell net, and the outer side of the
insulation layer and the outer side of the pull-out wall shell net are located in the same plane; the hollow steel section column I, the steel truss beam, the pull-out wall shell net and the prestressed
floor slab constitute a basic building module. The flexible arrangement of the basic building module in three-dimensional space constructs buildings of various shapes; the design, factory production and construction costs of the present invention are low, and it has huge market promotion potential.