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| 摘要: |
| 为研究环境因素对结构混凝土耐久性的影响,现场检测了宁波某海工码头工作平台不同结构区域的结
构混凝土耐久性能. 检测结果表明碳化深度和钢筋保护层厚度的特征值与设计值的比值为大气区>水位变动区
>水下区;混凝土表面氯离子浓度和碱含量为水下区>水位变动区>大气区;表观氯离子扩散系数为水位变动区>
水下区>大气区. 大气区混凝土易受CO2 侵蚀而导致混凝土钢筋保护层劣化. 有害介质氯离子与CO2 共同侵蚀
导致水位变动区混凝土钢筋锈蚀和钢筋保护层劣化. 作业时间有限和环境恶劣降低了水下区混凝土对钢筋的
保护能力,导致钢筋锈蚀速度和钢筋保护层劣化加快. |
| 关键词: 环境因素 结构混凝土 耐久性 检测与评估 |
| DOI： |
| 分类号: |
| 基金项目:西部交通建设科技支持项目(2006ZB01-2);金陵科技学院博士启动项目(JIT 40610042) |
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| Tests and evaluation of structural concretedurability at Ningbo marine wharf |
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| Abstract: |
| In order to study the influence of environment factors on the structural concrete durability, the durability
properties of concrete at different structural regions of the working platform of a marine wharf in Ningbo are tested.
The test results show that the carbonation depth and the characteristic value and designed value of bar protective
layer thickness change from high to low, namely those in the atmosphere zone are greater than those in the water
level fluctuating zone, and those in the water level fluctuation zone are greater than those in the underwater zone.
The change in the apparent chloride concentration and alkali content of the concrete is: that in the underwater zone
is higher than that in the fluctuating water level zone and that in the fluctuating water level zone is higher than that
in the atmosphere zone. In terms of the apparent chloride diffusion coefficients, the fluctuating water level zone is
greater than the underwater zone and the underwater zone is greater than the atmosphere zone. Concrete in the
atmosphere zone is much exposed to CO2, which results in deterioration of the protective layer thickness. The
combined action of chloride ion with CO2 erosion leads to deterioration of the protective layer thickness in the
fluctuating water level zone. The limitation of operation time and bad environment lower the ability of reinforced
protection, and a faster steel corrosion and the deterioration of the layer thickness can be found in the underwater
zone. |
| Key words: environmental factors structural concrete durability inspection and evaluation |
