低品位全珊瑚骨料混凝土强度提升技术研究

Research on Strength Improvement Technology of Low-grade Coral Aggregate Concrete

采用筒压强度为3.72 MPa的低品位全珊瑚骨料配制LC30与LC50混凝土,针对低品位全珊瑚骨料混凝土28 d抗压强度很难超过50 MPa的问题,开展了基于水胶比、骨料预湿和人工海水拌养的抗压强度提升技术研究。结果表明:珊瑚骨料混凝土抗压强度随水胶比减小先增后减,水胶比0.20为极限水胶比,此时混凝土抗压强度最高;预湿骨料对水胶比较大的LC30混凝土强度提升较小,对于低水胶比的LC50珊瑚骨料混凝土强度提升明显;海水拌养有利于珊瑚骨料混凝土早期强度增长,但对28 d强度没有显著影响。

LC30 and LC50 concrete were prepared with low-grade coral aggregate with a cylinder crushing strength of 3.72 MPa. Aiming at the problem that the 28 d compressive strength of low-grade coral aggregate concrete is difficult to exceed 50 MPa, the compressive strength improvement technology based on W/B, aggregate pre-wet and artificial seawater mixing is studied. The results show that the compressive strength of coral aggregate concrete first increases and then decreases with the decline of W/B and 0.20 is the limit of water-to-binder ratio with a highest compressive strength. The pre-wet aggregate has less influence on strength improvement for LC30 coral aggregate concrete with larger W/B, while the strength of LC50 coral aggregate concrete with low W/B is obviously improved. Artificial seawater mixing is beneficial to the early strength growth of coral aggregate concrete, but has no significant effect on 28 d compressive strength.