1. Introduction

The shaft grouted bored pile construction technique, initially proposed by Gouvenot and Gabaix in the mid-20^th century, gained widespread application from the 1990s onward in regions including Hong Kong, Thailand, and Vietnam. This technique is distinguished by its ability to enhance shaft friction, significantly improving load distribution along the pile’s length. By increasing load-bearing capacity and reducing settlement, shaft grouting is ideally suited for high-load applications in structures such as high-rise buildings, bridges, and offshore facilities.

Previous empirical research and projects demonstrated that bored piles using shaft grouting can achieve up to twice the load-bearing capacity of conventional bored piles. The optimization of pile performance reduces the number of piles, delivering substantial cost and time efficiency in construction.

Shaft grouting enhances pile load capacity through several key mechanisms: (1) a grout layer envelops the pile shaft, enhancing contact with surrounding soil; (2) densification of soil disturbed or loosened during drilling; (3) cementation of soil particles around the pile shaft; and (4) grout infiltration into voids, cracks, or gaps within the soil matrix, expanding the effective contact area between the pile shaft and surrounding soil.

2. Scope of application

Due to its capacity to enhance load-bearing performance, shaft grouting is commonly employed in the pile construction of high-rise and supertall buildings, bridges, and offshore structures.

3. Construction sequence

The construction sequence of shaft grouted bored pile technique is illustrated in Fig. 1.

Figure 1. Construction sequence of shaft grouted bored pile technique

4. Technology video