高海拔地区RPC120混凝土的配合比设计及工程应用

Mix Proportion Design and Engineering Application of RPC120 Concrete in High Altitude Area

本文研究了在高海拔地区RPC120-RC-GB/T 31387等级混凝土的配合比设计方案,同时结合当地实际情况,放弃使用特殊级配石英砂,改用当地的河砂配制RPC120-RC-GB/T 31387等级混凝土,并检测其力学和耐久性能。在实际工程应用过程中发现,在高原低气压地区,混凝土的气-液界面结构明显异于常压地区,通过调整外加剂和配合比妥善的解决了该问题。试验和现场的实践证明,使用当地的河砂也可以在现场生产出RPC120-RC-GB/T 31387等级的混凝土,且能够实现在高原低气压环境下的浇注成型,并保证其力学及耐久性指标达到设计要求。

The mix proportion design scheme of RPC120-RC-GB/T 31387 concrete in high altitude area is studied,at the same time,in combination with the local actual situation,the use of special graded quartz sand was abandoned,and the local river sand was used to prepare RPC120-RC-GB/T 31387 grade concrete,and its mechanical and durability properties were tested.In the process of engineering application,it is found that the airliquid interface structure of concrete in the plateau low-pressure area is obviously different from that in the normal pressure area,and this problem is properly solved by adjusting the admixture and mix ratio.Through laboratory tests and field practice,it is proved that RPC120-RC-GB/T 31387 grade concrete can be produced on site by using local river sand,and it can be cast and formed under the environment of low pressure in plateau,and its mechanical and durability indexes can meet the design requirements.