Ground Engineering

In a world where building and development take place on increasingly varied terrains, the ability to respond to the nature and intrinsic variability of the soil is of pivotal importance. And at HSL, knowledge of the soil we work on, flexibility in approaching our work and a high degree of know-how enables us to confidently overcome geotechnical challenges to help achieve safe and viable development in all kinds of locations.


Forming the very basis of construction, piling is an activity that requires experience and knowledge. Supported by a diverse range of up-to-date piling equipment, we are able to deliver piling works of high quality to ensure a safe and stable foundation for any kind of construction activity.

Widely used as an economical solution for the foundation of high-rise buildings, bored piling cannot be carried out effectively without extensive experience and knowledge. In normal soil conditions, the construction of bored piles involves installation of temporary steel casings prior to boring by means of a rotary rig. In extremely unstable and weak soil conditions, polymer or bentonite slurry is used to prevent collapse of the pile shaft. To overcome ground variability and minimize on-site vibration and noise levels, HSL performs detailed soil analysis and mitigation studies before selecting the most appropriate drilling technology, thus enabling us to build a safe foundation with minimal disruption to the surrounding areas.

Micro piles are small diameter piles used to carry vertical loads for small structures such as lift shafts and walkway shelters, particularly in congested built-up environments. It offers a viable alternative to conventional piling techniques, particularly in restricted access or low headroom situations. Our expertise in micro piles ensures that installations are carried out with a high level of quality control, low noise levels and minimum on-site vibration.

Earth Retaining Structures

Earth retaining structures are used to hold back earth and provide support for vertical grade changes. With a wealth of knowledge in installing earth retaining structures, HSL is able to construct diaphragm/slurry walls, contiguous bored pile walls and secant pile walls, ensuring a high degree of safety and durability for all of our work.

Diaphragm walls are barriers or earth retaining walls made of reinforced concrete and constructed in the ground by means of a trenching process. Slurry walls are similar, except that they are non-structural barriers and hence, more commonly used as cutoff walls to impede deep groundwater flow. Through the construction of diaphragm and slurry walls, HSL provides economical solutions for developing multilevel basements and for controlling environmental groundwater problems.

Contiguous bored pile wall is one of the most common earth retaining systems, where the bored piles are constructed in lineal sequence and side-by-side with minimum clear spacing. It is particularly suitable in situations where site boundary restrictions prohibit the use of alternative forms of soil retaining systems, for example where adjacent structures are immediately adjoined to the wall boundary. By tailoring methods and specifications to suit particular site conditions, HSL designs and builds walls that are safe and robust.

A secant bored pile wall is another type of earth retaining system using the bored piling technique of construction. Secant bored pile walls consist of overlapping primary piles which are often referred to as female piles and secondary (male) piles. Depending on ground conditions and design requirements, secant bored pile walls are a cost effective way to provide alternative retaining wall systems especially in controlling water flow, and allowing basement excavation with limited pumping in granular or water bearing strata.