中文摘要：

为了考察膨胀剂对高延性水泥基复合材料（HDCC）力学性能和变形的影响,研究了掺膨胀剂HDCC的抗折和抗压强度、弯曲韧性、单轴拉伸性能和干燥收缩变形,并采用环境扫描电镜观察了膨胀剂在HDCC中的水化产物形貌。结果表明：膨胀剂对HDCC的抗折强度基本无影响,但略微降低了抗压强度,增大了HDCC的弯曲强度和极限拉伸强度,降低了HDCC的韧性和延性;抗压强度降低幅度在15%以内,极限拉伸应变降低幅度在1/4以内,韧性降低幅度为28%～45%。掺膨胀剂后,HDCC在前2 d有一定的膨胀变形,而长龄期收缩变形值降低了1/4～1/2。膨胀剂水化产生的钙矾石提高了HDCC的体积稳定性。

英文摘要：

The effect of expansive agent on the mechanical properties and deformation behavior of high ductility cementitious composites （HDCC） was investigated via measuring flexural/compressive strengths, flexural toughness, uniaxial tensile and drying shrinkage. The hydration product of expansive agent was determined using scanning electron microscopy. The results show that the expansive agent has no effect on the three-point flexural strength and slightly reduces the compressive strength. The use of expansive agent increases the four-point flexural strength and the ultimate tensile strength, and decreases the flexural toughness and the ductility. The compressive strength is reduced by 〈15%, the ultimate tensile strain is decreased by 〈 1/4, and the toughness is reduced by 28%-45%. The HDCC with expansive agent has a considerable amount of expansive deformation at age of 2 d, and the long-term shrinkage deformations are reduced by 1/4 to 1/2. The ettringite, as the hydration product of expansive agent, improves the volume stability of HDCC.