Machines and system for 3D printing are disclosed. One machine includes a machine frame having a plurality of ground engaging elements to facilitate movement of the machine frame, a telescoping boom pivotably coupled to the machine frame and configured to pivot along at least a horizontal plane, a material line coupled to the boom and configured to convey a material therethrough, a printhead coupled to the boom and in fluid communication with the material line to receive the material and to dispense the material, and a controller configured to receive 3D printing information and to convert the 3D printing information into positional coordinates of the printhead, wherein the controller is to cause movement of the boom to position the printhead based at least on the position coordinates.

A concrete panel system includes first, second, and third rectangular precast concrete panels, each defining a respective top edge, bottom edge, and first and second lateral edges. A first type connector is formed in the concrete material at least along the top edge of the first panel and along the first lateral edge of the first panel. A second type connector is formed in the concrete material at least along the second lateral edge of the second panel, and along the bottom edge of the third panel. The first type connector and the second type connector are configured to connect together, and a cavity is formed between the respective panel edges. This cavity extends along both the top edge of the first panel and the first lateral edge of the first panel to facilitate positioning reinforcing bar traversing a corner of the first or second panel.

In an earthquake resisting design method of a PC construction, a column and a beam, which are high-strength precast prestress concrete members, are joined by binding juncture with a prestressing tendon. A grout is filled and bonded. A first stage linear resilient design is employed, where all construction members are not damaged, for earthquakes up to a predetermined earthquake load design value. A second stage linear resilient design is employed, where earthquake energy is absorbed by breakage of the bond of the grout, and principal construction members are not damaged, for earthquakes exceeding the predetermined earthquake load design value. By employing a non-linear resilient design in which the first stage linear resilient design and the second stage linear resilient design are combined, an earthquake-resisting design level is significantly increased, and the construction can resist earthquakes exceeding a seismic intensity 6 upper.