Preliminary study on the effect of different treatments on setting of cement reef and pH value and salinity of leaching solution
The addition of quick-setting ingredients,seawater immersion,drying will affect the setting of the cement reef and the leaching solution quality after casting.The setting time of cement reefs with different ratios of accelerators was measured,and the pH and salinity of 300 mL of seawater within the cement reefs treated differently were studied.The results showed that when the mass ratio of accelerators increased from 0∶10 to 1.5∶10,the initial setting time of algal reefs was shortened from 245 minutes to 0.17 minutes,and it was found that adding accelerators would release alkaline leaching substances from reefs is relatively slowlier and the fluctuation range of leaching solution salinity on the cement reef is smaller.The pH value of the leaching solution with the reefs of the two groups showed a significant upward trend(P＜0.05)from 0 to 16 days,and the pH value of the leaching solution was up to 12.30.The salinity of group A(without accelerator)showed a trend of increasing gradually,while the salinity of reef B(with accelerator)showed a trend of decreasing early and then increasing.The salinity of group A was significantly higher than group B(P＜0.05).Seawater immersion of cement reefs also affected the salinity and pH value of the leaching solution.The pH value of the leaching solution of the two groups of reefs in the first immersion changed significantly(P＜0.05)compared with the second and third immersion(P＜0.05),while the pH value of the second and third immersion did not change significantly(P＞0.05).When the reefs of A group were put first into seawater,the salinity of leaching solution increased from 34.66 to 38.20,and the salinity of leaching solution fluctuated between 33.50 and 35.00 in the last two immersion.The leaching solution salinity of group B all showed a trend of decreasing first and then increasing and fluctuated between 33.50 and 34.90 during the three times.The carbonization treatment can reduce the impact of the cement reef on the pH value of leaching solution.The longer the carbonization time is,the slower the leachate pH value rises,and the longer it takes to stabilize.The experimental results can provide data reference for the application of cement-based reefs in marine ranching.
万方数据
维普
