市政道路膨胀土环境路基填筑施工改良技术

Construction Improvement Technology of Subgrade Filling in Expansive Soil Environment for Municipal Road

市政道路路基是道路工程最底层的结构物,是整个道路的受力基础,应具有足够的强度和稳定性。在膨胀土环境下如果不进行妥善处理而直接填筑施工会导致市政道路发生沉降变形、路面开裂、甚至在严寒天气作用下产生滑坡等病害,严重威胁道路行车安全。为改良东北严寒地区膨胀土地质环境下填筑路基的施工技术,实践中采用了最佳石灰掺量试验、最佳闷灰时间确定、工地现场修筑试验段等方法,并在哈尔滨新区丁香大道市政道路施工中进行应用。得出如下结论:处理膨胀土环境的最佳石灰掺量为6%、最佳闷灰时间为2 h、通过无侧限抗压强度试验检测不同龄期路基土的强度,其强度符合要求。

The municipal road subgrade is the bottom structure of road engineering,which is the load-bearing foundation of the entire road and should have sufficient strength and stability.If the expansive soil environment is not properly treated and directly filled,it can lead to settlement and deformation of municipal roads,road cracking,and even landslides under the influence of severe cold weather,seriously threatening road driving safety.In order to improve the construction technology of filling roadbeds under the expansive soil environment in the severely cold region of Northeast China,innovative methods such as the best lime content experiment,the determination of the best compaction time,and the construction of test sections on site were adopted;And applied in the construction of municipal roads on Dingxiang Avenue in Harbin.The following conclusion has been drawn:the optimal lime content for treating expansive soil environment is 6%,the optimal lime filling time is 2 hours,and the strength of roadbed soil at different ages has been tested through unconfined compressive strength experiments,and its strength meets the requirements.