Geotechnical Services
The company’s geotechnical division was the original arm of the business founded in 1966. Again we have diversified in this field to cope with most of todays onerous construction requirements ranging from simple trial pitting to rock coring, mini piling and ground stabilisation works with in house professional indemnity for foundation design.
With over 30 years of experience Denver Construction Services can offer the client the complete package for the initial stage of a variety of construction projects.
Associated methods of geotechnical investigation undertaken, and services provided
- Site Investigation
- Piling
- Rotary Core Drilling
- Rotary Percussive Open Hole Probing
- Drilling & Grouting for Ground Stabilisation
- Water Wells
To view our geotechnical services in more detail please click the links below
Our clients commission all forms of site work. Clients typically embrace consultants, engineers, local authorities and major construction company’s as well as the self builder. The company is able to offer a unique service in this specialist geotechnical field. From initial enquiry and preparation of desk/feasibility study reports we are able to recommend and undertake the most appropriate and economic site investigation with subsequent factual and interpretive reports to follow.
Denver Construction Services have in house experts who are then available to the client to assist in the design of all types of foundation solutions. In marginal ground we are also able to provide a full ground stabilisation service if required.
Denver Construction Services specialise in providing solutions to all types of foundation problems and offer a full design and installation package for all mini piling requirements. Our fleet of TD610.W hydraulic mini piling/drilling rigs (see opposite) are designed to drill up to 500mm diametre augered piles, and can also be used for rotary percussive bottom driven steel tube piling. With a 100mm diametre hollow main shaft in the rotation head concrete can be pumped directly to the bottom of the pile for true C.F.A work. This makes the TD610 the ideal mini piling rig to overcome any difficult operational conditions such as restricted access, difficult ground, limited headroom and environmental restrictions.
Steel driven cased piles offer a suitable alternative for a wide range of conditions when piling into sands, gravels, clays, and typically when driving through fill, overburden and into bedrock. The steel tubes used are between 2-3mtrs in length and are welded together during the drilling procedure. A single steel bar or cage is then installed and infilled with concrete or grout . The advantage of cased piles is minimal spoil generated, good axial and sheer capacity, prevention of concrete/grout loss (thus ensuring pile integrity) and minimal site preparation.
Denver Construction Services offer vast experience and a wide range of drilling rigs to suit the majority of investigation applications. The rotary percussive technique pictured opposite specialises in the investigation of old mine workings, mine shaft entries, old culverts and is ideal for drilling in all types of rock strata. All drilling rigs also carry strings of overburden steel casing which enables continuous drilling through difficult sands and gravels strata until solid rock has been penetrated. Once the required drilling depth has been achieved, the drill rods can be retrieved and the steel overburden casing extracted. Denver Construction Services have open hole percussive probing rigs that can achieve drilling depths of up to 100 mtrs if required with tyre wheel and track rigs available to suit all site conditions.
When required, all Denver Construction Services rigs can be adapted to undertake diamond rock coring. Steel core barrels with diamond heads are used to take rock samples at required depths for analysis. Plastic tube liners are used to case the samples for testing analysis.
In conjunction with site investigation drilling, Denver Construction Services have a vast range of grout mixers and pumps to suit all types of ground stabilisation and void grouting project applications. Typical examples of contracts continually undertaken are the grouting up of old mine working voids, mine shafts, culvets, broken ground and abandoned/redundant sewer and water pipes.
Grouting offers numerous cost cutting options, in relation to excavation, demolition and reinstatement costs.
The attached photographs show a typical grouting scenario undertaken by Denver Construction Services. On this occasion old mine working voids were found present on a “proposed factory extention” plot of land. A series of 100mm diametre holes were rotary percussively drilled into the void areas and plastic grout inserted.
Denver Construction Services then use an air driven bulk pan mixer complete with sandpiper grout pump to fill all the void areas throughout the proposed factory extension area. On this occasion as with most grouting job applications a 9:1 ratio PFA/Cement grout mix was used with bulk loads of 20 ton of PFA being used.
Denver Construction Services also supplied in house geotechnical engineers to oversee the grouting procedure through the working programme.
With water charges rising sharply private systems provide cost effective alternatives. Boreholes for example reduce charges by over 90% with the water costing less than 10p/1000 litres.
Borehole drilling for domestic and industrial water supply is one of the utilities provided by DLS. Clients include British Telecom, the ministry of Defence, Farmers and industrialists. Our water wells supply houses, offices, vehicle washing facilities, golf courses and leisure complexes.

