沙漠公路风积沙台背回填技术研究

Research on Backfilling Technology behind Aeolian Sand Abutment on Desert Highway

针对沙漠高速公路涵洞台背回填困难问题,结合沙漠地区风积沙资源丰富的工程环境特点,开展风积沙台背回填关键技术研究。通过检测洒水压实法下压路机静压一遍+振压一遍和推土机静压一遍+铲运车收光一遍两种碾压工艺对风积沙台背压实度的影响,以及采用水沉法下不碾压或装载机静压一遍两种碾压工艺对风积沙台背压实度的影响,评价风积沙台背回填最优压实方法与碾压工艺;通过超载方式对台背部分进行预压,观测其沉降值,评价风积沙台背稳定性。研究结果表明,相比于水沉法,洒水碾压法仅需将表层风积沙湿润,其用水量不足水沉法的十分之一,经济效益显著;相比推土机静压一遍+铲运车收光一遍的碾压工艺,压路机静压一遍+振压一遍的方法对机械资源需求量低,而且可满足连续作业需求,施工效率显著;此外,采用该方法的风积沙回填台背的稳定性良好,降低了台背不均匀沉降风险;同时,因风积沙材料的透水性良好,可较大程度地避免水损害。

Aiming at the difficulty of backfilling behind culvert abutment on the desert expressway,combined with the characteristics of the engineering environment in the rich aeolian sand of desert area,the key technology of backfilling behind the aeolian abutment is studied.The best compaction method and the rolling processes of backfilling behind the aeolian sand abutment are evaluated by testing the influence of two rolling processes under the hydraulic sprinkling and compaction method of one static press of road roller+one vibration press and one static press of the bulldozer+one finish of the scraper on the compaction degree behind the aeolian sand abutment,and the influence of two rolling processes of non-rolling by water sinking method or one static press by loader on the compaction degree behind the aeolian sand abutment.The stability behind the aeolian sand abutment is evaluated by using the overloading method to preload the section behind the abutment and to observe its settlement value.The study result shows that compared with the water sinking method,the watering rolling method only needs to wet the surface aeolian sand.Its water consumption is less than one tenth of that of water sinking method,and its economic benefits are remarkable.Compared with the rolling process of the bulldozer static press once+the scraper truck receiving the light once,the method of one static press of road roller+one vibration press is low in mechanical resource demands.Moreover,it can meet the needs of continuous operation and the construction efficiency is remarkable.In addition,the stability of backfilling behind the Aeolian sand abutment by this method is good,and the differential settlement risk behind the abutment is reduced.At the same time,the water damage can be greatly avoided because of the Aeolian sand material with the good water permeability.