Sigra has over nearly three decades operated in a range of engineering fields associated with the ground. These have included both coal and metalliferous mining, civil engineering works and shallow gas. The common theme through this work is the necessity to understand the geology as this is the model into which the engineering works are inserted. Sigra then measures what is relevant to the engineering works within the context of the geology. To do this Sigra has created a suite of suitable field and laboratory tools. The emphasis with these is to measure real properties rather than some index and to use these values in Sigra’s models of the ground’s behaviour which include stress and strain and fluids. The purpose of these is to enable optimal designs to be developed. In some cases Sigra has gone on to provide complete solutions in the form of these designs or items of equipment to deal with particular challenges.

Sigra has always worked on the basis that the laws governing how rock and soil behaviour are fundamentally the same whether the case involves a foundation excavation or a borehole at 2000 m depth. What is different is the stress level, strength of the material, fluid pressure and the shape of the hole to be created in the ground. This ability to work from the first principles has benefitted the company and its clients enormously. It helps removes cloak of mystery and jargon with which each discipline of engineering likes to shroud its own area of operations thus reducing the problem on one of fundamentals.

By working across disciplines Sigra has been able to transfer technologies between these. For example the well testing techniques used in the petroleum industry can be used to great advantage to test for groundwater in tunnelling applications. In a similar vein understanding the structural behaviour of plate structures is beneficial to analysing the collapse of a sedimentary sequence into the goaf of a longwall coal mine. This breadth of experience is immensely valuable.