Cement concrete is widely used in pavement, bridge decks and expansion joint anchorage zones. It is prone to cracking, potholes, spalling and other diseases during use. Cement-based repair materials generally have problems such as a long curing period, low bonding strength with existing concrete, and insufficient mechanical properties. Given this, this paper proposes an early-strength high-ductility cement composite material with the goal of short curing age, excellent tensile mechanical properties and relatively low price. The tensile mechanical properties of the composite material at different ages were tested, and the tensile constitutive model of the composite material was proposed. The results show that when the fly ash content is about 50 wt.%, the PVA fiber content is about 2%, and the sand-binder ratio is 0.36–0.50, the tensile properties of the early strength high ductility cement composite material at each age are better. Under the condition of optimum mix ratio, the tensile strength of 1, 3 and 28 d of early strength high ductility cement-based composites reached 4.58 MPa, 4.67 MPa and 4.64 MPa respectively, and the strain corresponding to 0.8 times of peak stress in softening section could reach 2%.

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Research on Axial Tensile Mechanical Properties of Early-Strength High Ductility Cementitious Composites

  • Wenhong Duan,
  • Jiaquan Yuan,
  • Li Xiong,
  • Weihong Jiang,
  • Huimei Li,
  • Lin Mou,
  • Xiaohua Yang,
  • Xiaomin Huang,
  • Weibing Xu,
  • Kun Yang

摘要

Cement concrete is widely used in pavement, bridge decks and expansion joint anchorage zones. It is prone to cracking, potholes, spalling and other diseases during use. Cement-based repair materials generally have problems such as a long curing period, low bonding strength with existing concrete, and insufficient mechanical properties. Given this, this paper proposes an early-strength high-ductility cement composite material with the goal of short curing age, excellent tensile mechanical properties and relatively low price. The tensile mechanical properties of the composite material at different ages were tested, and the tensile constitutive model of the composite material was proposed. The results show that when the fly ash content is about 50 wt.%, the PVA fiber content is about 2%, and the sand-binder ratio is 0.36–0.50, the tensile properties of the early strength high ductility cement composite material at each age are better. Under the condition of optimum mix ratio, the tensile strength of 1, 3 and 28 d of early strength high ductility cement-based composites reached 4.58 MPa, 4.67 MPa and 4.64 MPa respectively, and the strain corresponding to 0.8 times of peak stress in softening section could reach 2%.