高性能混凝土及其配合比设计探讨

长期以来,人们对工程仅要求和注重强度,忽视了由于追求水泥早强、高强及生产质量下降、使用环境恶劣等原因引起的混凝土过早劣化现象,此时的混凝土配合比设计也主要以满足强度要求进行.混凝土的过早劣化迫使人们注重其耐久性.高性能混凝土以耐久性为主要指标.对不同的工程,高性能混凝土有不同的"特殊性能组合".抗渗性是普通混凝土耐久性的关键指标,然而在具有高抗渗性的高性能混凝土中某些侵蚀性离子仍能在其中扩散,对此用侵蚀性离子的扩散性(以扩散系数表示)来评定其耐久性更为合理.高性能混凝土配合比设计以耐久性为目标,即满足侵蚀性离子在高性能混凝土中的低扩散性.

High Performance Concrete and its Mixing Design

The concrete strength has been attached great importance to in projects for a long time,while the concrete deterioration caused by early and high strength cement,low production quality and abominable using environment has been neglected.And the concrete mix proportion is mainly designed to meet the need of strength.However,early concrete deterioration forces people to pay more attention to its durability.As durability is a key indicator for high performance concrete(HPC),HPC for different projects requires "different special performance combination ".Meanwhile,impermeability is the key indicator for general concrete;however,some erosion ion can still proliferate in HPC with high impermeability.Therefore,it is more reasonable to assess HPC durability according to ion proliferation coefficient.Aiming at the durability,the mix proportion design for HPC tries to meet the requirement of low ion proliferation in HPC.