Abstract Seawater is highly corrosive, and it is very easy to cause erosion and destruction of tunnel lining structure through the weak area of surrounding rocks. In order to ensure the durability of the supporting structure, the mix proportion of corrosion-resistant grouting materials with ordinary Portland cement as the base material is designed by means of adjusting the content of water reducer, accelerator and high molecular polymer, and the corrosion-resistant index test and field grouting effect test are carried out on grouting materials with different mix proportions. The indoor test results show that the strength corrosion coefficient of the grouting material sample (water-cement ratio:0.65~1.0) after 360 d soaking in seawater is greater than 0.80, with good volume stability. In order to accelerate the erosion rate, the test sample is soaked in saturated MgSO4 solution, and the strength corrosion coefficient of the grouting material sample (water-cement ratio: 0.65) after 360 d soaking is greater than 0.80, and still with good volume stability. The strength of set grouts is tested through field grouting test. The test results show that the average point load strength of set grouts after 180 d soaking in saturated MgSO4 solution is 0.931 kN, which is 5.5% lower than the average strength 0.984 kN of non-soaked samples, further verifying the corrosion resistance of grouting materials.
Abstract：
Seawater is highly corrosive, and it is very easy to cause erosion and destruction of tunnel lining structure through the weak area of surrounding rocks. In order to ensure the durability of the supporting structure, the mix proportion of corrosion-resistant grouting materials with ordinary Portland cement as the base material is designed by means of adjusting the content of water reducer, accelerator and high molecular polymer, and the corrosion-resistant index test and field grouting effect test are carried out on grouting materials with different mix proportions. The indoor test results show that the strength corrosion coefficient of the grouting material sample (water-cement ratio:0.65~1.0) after 360 d soaking in seawater is greater than 0.80, with good volume stability. In order to accelerate the erosion rate, the test sample is soaked in saturated MgSO4 solution, and the strength corrosion coefficient of the grouting material sample (water-cement ratio: 0.65) after 360 d soaking is greater than 0.80, and still with good volume stability. The strength of set grouts is tested through field grouting test. The test results show that the average point load strength of set grouts after 180 d soaking in saturated MgSO4 solution is 0.931 kN, which is 5.5% lower than the average strength 0.984 kN of non-soaked samples, further verifying the corrosion resistance of grouting materials.
JIAO Lei
.Study on Corrosion Resistance of Grouting Materials for Subsea Tunnels and Its Engineering Application[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(1): 256-262
2022, Vol. 59 