The invention discloses a volcanic accumulation layer foundation treatment method. The volcanic accumulation layer foundation treatment method specifically comprises the following steps of construction preparation; measuring and setting out; leveling the down-the-hole
drill in place; the down-the-hole
drill drills to form a hole to form a first
drill hole; shifting the down-the-hole drill; a screw
pile drilling
machine is in place; a drill rod of the screw
pile drilling
machine drills downwards along the first
drill hole to form a second
drill hole; a mixture is injected into the second
drill hole, and after the second drill hole is filled with the mixture, the drill rod is pumped and lifted to the
earth surface at the specified speed; and the next
pile is shifted and constructed. The construction method is applied to
subgrade screw pile foundation treatment under the
volcanic ash geology, efficient construction can be achieved through the method, the construction effect is good, and the overall method is economical. The method is simple and safe in construction, suitable for foundation treatment, especially for
volcanic ash stratum conditions, high in applicability and capable of guaranteeing the construction quality of the screw pile.