Drilling operations in construction foundation projects
The rotary drilling rig is a construction machine suitable for drilling operations in construction foundation projects. It is mainly suitable for construction in sandy soil, cohesive soil, silty soil and other soil layers, and is widely used in the construction of various foundations such as cast-in-place piles, continuous walls, and foundation reinforcement. The rated power of rotary drilling rigs is generally 125 to 450kW. The output torque is 120~400kN·m, the maximum hole diameter can reach 1.5~4m, and the maximum hole depth is 60~90m, which can meet the requirements of various large-scale foundation construction.
Pile foundation consists of two parts: cap platform and pile group. The cap is set on the top of the pile, connecting the individual piles into a whole, and evenly transmits the load of the superstructure to each pile, and then from the pile to the foundation pile. According to the different ways of transmitting force, it is divided into friction piles and end-bearing piles. Manually dug holes for cast-in-place piles. Single and multi-tube high-pressure jet grouting piles, drilled and punched piles, rotary digging piles, CFG piles, deep mixing piles, powder spray piles, gravel piles, chemical filling, pipe piles, precast concrete piles, static pressure piles and cast-in-place piles hammered pile
This type of drilling rig generally adopts a hydraulic crawler-type telescopic chassis, a self-lifting and foldable drill mast, a telescopic drill pipe, automatic detection and adjustment of verticality, digital display of hole depth, etc. The whole machine generally uses hydraulic pilot control and load sensing. It has the characteristics of light operation and comfort. The main and auxiliary winches can be used in various situations on the construction site. This type of drilling rig is used with different drilling tools and is suitable for dry (short spiral) or wet (rotary bucket) and rock formation (core drill) drilling operations. It can also be equipped with a long auger, underground diaphragm wall grab, and vibrating pile hammer. etc., to achieve a variety of functions, mainly used in municipal construction, highway bridges, industrial and civil buildings, underground diaphragm walls, water conservancy, anti-seepage slope protection and other basic construction. Domestic experts believe that rotary drilling rigs will still have a large domestic market in the next few years.
