Trenchless Feasibility Study

Part of the McAllister Group

There are several aspects to be considered whether a trenchless solution for construction is feasible, and it is important that you have the right team involved - McAllister Specialist Construction can help.

The various aspects involved include:

Information gathering

Starting with desktop survey, historical information gathering- from 3rd parties or stakeholders carry out research contacting stakeholders or asset owners to obtain existing information such as existing maps, historical boreholes or existing GIS map. This step will often dictate what site surveys are required from baseline vibration monitoring to …

Geological information

Sub surface information will be key to the success of the project. The site investigation that gives up the geological information should be guided be an experienced person who understand the information required. For example boreholes – either percussive or rotary core, should be properly positioned so as not to cause interference, and to give a guide as to the type of ground likely to be encountered.

Sampling and testing

Sampling and testing of the ground can also be critical yielding various information about the strength and jointing plane of the ground. Testing for contamination-

Hydrological survey

Often over looked but can be critical giving a view of the ground water or aquifers that may be present. Checking the ground water level at regular stages and creating a

Trenchless Construction methods available and design

Based on available information an optioneering exercise in trenchless civils engineering, considers depth, expected ground, surface environment and structures, loading, surface structure impact, environmental impact, type of structure required pipeline to be installed by auger, guided auger, HHD, pipejacking, microtunnelling. Once the methods have been chosen early design calculations can show different factors that may influence the type of trenchless construction technique selected. Settlement calculations –structural calculation- Face loss calculations- skin friction-thrust wall calculations -volume of material excavated – grouting or vibration assessments on the surface assets.

Cost Modelling

All aspects of the entire lifecycle must be factored in to get a complete picture so an informed economic decision on the project can be made. That is the Total expenditure (Totex), which includes ; The capital cost to design and install, up to commissioning of the project (Capex), operational & maintenance (OPEX) cost and the replacement (REPEX) or decommissioning costs. Many projects need to consider the environmental impact and the cost.

Risk Analysis

Identify the hazard and the risks the pose to the project and record in a register and weight each with an impact. Mitigation methods available and the overall cost impact from construction risks to economic risks.

Decision Making

At every step in the feasibility process a clear record of the decisions that are made need to be documented. This helps track and show the influence and factors that informed the decisions made making a fully accountable and traceable feasibility approach.

Environmental Considerations

Trenchless Construction Solutions can typically offer a better environmental footprint that traditional construction methods and as we move forward to a greener we need to consider these impacts- the carbon footprint, the disruption costs (increased traffic e.g), the muck away and the materials. All these elements need to be assessed.

There are many questions that need to be asked and answered McAllister Specialist construction can assist you making the correct decisions on your trenchless projects. Please contact us to discuss your trenchless project.