条形药包爆炸挤密黄土路堤横向影响规律

Lateral influence rules on explosion-compacted loess embankment by linear explosive bars

为了合理设计既有公路路堤爆炸挤密钻孔的平面布置方案,以爆炸挤密加固某高速公路黄土路堤为例,研究了条形药包爆炸挤密黄土路堤的横向影响规律。先根据该高速公路实际几何尺寸和材料参数建立有限元模型,然后用ANSYS/LS-DYNA分等横截面不等长和等长不等横截面两类条形药包共计16种工况进行数值模拟,得出爆腔水平半径、土壤密度峰值及其位置和爆炸挤密黄土路堤横向影响半径的变化规律,此外还拟合出横截面为2支药管组成的条形药包爆炸挤密后土壤的密度增量与该点距爆心的水平距离和药量之间的关系表达式。最后,结合工程实例,说明了上述规律在施工方案设计中的应用。

In order to rationally design the plane layout scheme of drilling holes for explosion compacting the loess embankment of an existing highway,this paper took the loess embankment of a highway reinforced by explosion compaction( EC) as an example and studied the lateral influence rules on EC with linear explosive bar.Firstly,a finite element model was established according to the actual geometry and material parameters of the highway. Then,based on the numerical simulation of sixteen cases carried out by ANSYS/LS-DYNA,the change rules of the horizontal radius of the explosion cavity,the peak values of soil density and their position,the lateral influence radius of explosion compacting loess embankment were obtained. These sixteen cases belong to two kinds of situations. One kind is of explosive bars with equal cross section and unequal length,while another one is of those with equal length and unequal cross section. Moreover,the relationship functions among the increment of soil density after EC with the explosive bar whose cross section was composed of two explosive tubes,the horizontal distance to the core of the explosive bar and the amount of explosive were fitted. Finally,combined with the actual EC engineering of the highway,the application of the above rules in the design of construction scheme was illustrated.