Method for 3D printing prefabricated modular buildings

A method for 3D printing a prefabricated modular building, comprising the following steps:

• step S10:
• performing concrete printing using a 3D printing device to obtain an intermediate module and connection modules;
• step S20:
• rotating the intermediate module by 90 degrees in a vertical plane to obtain a prefabricated module;
• and
• step S30:
• assembling the prefabricated module and the connection modules together to form the prefabricated modular building,
• wherein step S10 comprises the following sub-steps:
• step S11:
• constructing a shape of the intermediate module using a support;
• wherein the support is steel bars, and interchanging horizontal steel bars and vertical steel bars in a practically desired building, so that after the intermediate module is rotated, directions of the steel bars are exactly the same as required directions for the steel bars in the practically desired building to ensure that the steel bars in the intermediate module can receive stresses properly;
• step S12:
• forming four faces of the intermediate module uninterruptedly by laying concrete layer by layer on the support using the 3D printing device;
• wherein the four faces of the intermediate module formed in step S12 are a top, a bottom, a first wall, and a second wall of the intermediate module, respectively, and the top, the bottom, the first wall and the second wall are connected with each other to form a ring structure;
• wherein the top, the bottom, the first wall, and the second wall are solid structure walls with thickness respectively;
• step S13:
• constructing stress bearing members on two opposite faces of the intermediate module to complete construction of the intermediate module;
• and
• step S14:
• forming at least two connection modules using the 3D printing device,
• wherein transitions between the top, the bottom, the first wall, and the second wall are arc transitions,
• wherein the 3D printing device adjusts an angle of a discharge direction of each of two discharge ports through a gear while adjusting a travelling rate in each of two directions along a horizontal axis (X) and a vertical axis (Y) of the intermediate module during printing of arc-shaped walls, so that the discharge directions of the discharge ports are always kept consistent with an angle of an arc-shaped trajectory of the steel bars, which realizes printing of a continuous and smooth arc-shaped wall during transition from horizontal axis (X) building coordinates to vertical axis (Y) building coordinates;
• and
• wherein the concrete discharged from the discharge ports on two sides of the steel bars wraps the steel bars located at a middle position between the discharge ports to form a thickness of the wall, and the wall printed each layer has a height which is the height of each layer.