Combination of the DTH hammer with rotary drilling in hard rock pile foundation

Abstract:

Rotary drilling technology has the advantages of low cost， high drilling rate and environmental protection， and is widely used in pile foundation engineering. However， conventional rotary drilling is very slow in drilling hard rock （compressive strength greater than 80 MPa）. In order to solve the slow advance problem with rotary drilling in hard rock， and in view of high penetration rate of the DTH hammer in drilling hard and brittle rock， the combination of the DTH hammer with rotary drilling rig was explored. This paper introduces the construction process of the combined DTH hammer and rotary drilling technology with respect to the construction of anti-slide piles in the Guanjing Base landslide treatment project， analyzes the rock breaking mechanism， and verifies the feasibility of the combined DTH hammer and rotary drilling technology. It can provide a useful reference for the construction of hard rock pile foundation projects.