摘   要：研究了轻集料种类及其在粗集料中所占比例、轻集料粒径与级配以及体积砂率对高强次轻混凝土的表观密度、抗压强度、抗拉强度和弹性模量的影响。试验结果表明，轻集料的种类及其在粗集料中所占比例对不同强度等级的高强次轻混凝土具有相似的影响规律，即当轻集料在粗集料中比例不超过50%时，混凝土的抗压、抗拉强度和弹性模量随轻集料掺量变化的变化并不明显，而超过50%时，则随着轻集料掺量增大而明显降低；高强次轻混凝土的力学性能随轻集料粒径减小而提高，间断级配对混凝土的力学性能影响不利；体积砂率存在最佳范围，约为40%左右。

Abstract: Effects of the types, the volume contents, the max-sides and the grading of lightweight aggregate and the volume rate of sand on the physical and mechanical properties of high strength semi-lightweight concrete (HSSC) were investigated. Test results show that tow types of lightweight aggregate have similar regularity of effect on the mechanical properties of different strength grade HSSC. When the volume rate of lightweight aggregate in coarse aggregate changes in un-exceeding 50%, its effect on the compressive strength, split tensile strength and elastic modulus of HSSC isn’t obvious, however when it’s in exceeding 50% the mechanical properties of HSSC decrease markedly with increase of the volume rate of lightweight aggregate. Besides, the mechanical properties of HSSC increase with reduce of the lightweight aggregate's max-side, and the gap-grading aggregate is disadvantage to the mechanical properties of HSSC, for HSSC the optimal volume rate of sand is at about 40%.