利用自制的混凝土三轴试验系统，通过１２７块试件，对国内尚未研究、国外也较少开展的轻骨料混凝土在常规三轴及真三轴状态下（包括两轴拉及三轴拉状态下）的变形特性进行了试验研究；分析了应力－应变关系的特点，并与普通混凝土三轴状态下的特性进行了比较，发现了轻骨料混凝土在三向高压应力比下其应力－应变曲线具有明显的平台流塑特性；讨论了中间应力对峰值应变的影响以及轻骨料混凝土体积应变规律，为建立轻骨料混凝土的本构关系和结构设计提供了依据． Using the self-made concrete triaxial test system, through 127 specimens, the lightweight aggregate concrete that has not been studied in China and is less developed abroad is under the condition of conventional triaxial and true triaxial conditions (including two-axis tension and triaxial tension. The deformation characteristics of the lower part are studied experimentally; the characteristics of the stress-strain relationship are analyzed, and compared with the characteristics of ordinary concrete in the triaxial state, the stress-strain of the lightweight aggregate concrete under the three-way high stress ratio is found. The curve has obvious platform flow characteristics; the influence of the intermediate stress on the peak strain and the volumetric strain law of the lightweight aggregate concrete are discussed, which provides a basis for establishing the constitutive relation and structural design of the lightweight aggregate concrete.