Under electron-beam irradiation of heteroshape-heteroscale structure of silica-shelled Ga microball-nanotube, an abnormally large and fast volume expansion of liquid Ga is observed. First, we analyze the processes and phenomena about experiment, and the abnormal expansion process can be regarded as a quasi-static process. Then in the framework of quasi-static thermodynamics, according to the Fourier heat conduction law the relative volume variation with temperature is further quantitatively discussed, and the relative expansion rate and expansion coefficient in system are obtained. At the same time it is found that abnormal expansion coefficient of system under electron-beam irradiation is 5-9 times the general thermal expansion coefficient. Finally, it is pointed out that the abnormal expansion is due to the gallium atom ionization effect and the retention effect resulting from a few electrons retaining in the liquid gallium system under electron-beam irradiation. In essence, both ionization effect and the retention effect make the particle densities of liquid systems increased dramatically, resulting in volume expansion abnormally large and fast of liquid Ga.