科尔沁沙漠区风积沙动力压实特性研究

Research on dynamic compaction characteristics of aeolian sand in desert region of Keerqin

沙漠区修筑公路,优质路基填料匮乏。依据就近原则,选用沙漠区储量丰富的风积沙作为路基填料,分析其矿物成分、化学成分、酸碱度、含盐量与级配特征。进一步探究不同试验方法(击实试验、振动台法、表面振动压实仪法)与试验控制条件下,风积沙干密度受因素控制的变化规律与压实特征。风积沙击实曲线与振动压实曲线均呈现"振实—振松—再振实"造成的"多峰"特征,振动法所得干密度一般优于对应含水率条件下击实试验所得干密度。振动台法在风积沙含水率接近饱和时振动的效果最好,风积沙的干密度最大,表面振动压实仪法3层填料的振动压实效果明显好于1层填料方式,进而可用于施工指导。

Quality subgrade filler is scare in the construction of highway in the desert area, aeolian sand is selected as subgrade filler which is massive in the desert area, of which the mineral composition, chemical composition, pH, salt content and gradation characteristic are analyzed according to the principle of proximity. The change laws of dry density of aeolian sand and compaction characteristics are explored by using different test methods, i.e. compaction test, shaking table test, surface vibration compactor method, and controlled conditions of test. Compaction curve and vibratory compaction curve of aeolian sand show the multimodal feature of vibration compaction, vibration loose and vibration compaction again;dry density by shaking table test is superior to the density by the compaction test under the same water content ratio. Maximum dry density of aeolian sand is attainted while the water content ratio is close to saturation by shaking table test which vibration effect is best. The effect of vibration compaction by three layers filler is better than one layer filler of surface vibration compactor method. The results can provide guidance for construction.