What is TT World:

Trenchless Technology World provides information about Decision Support Systems that are being developed by the Trenchless Technology Center at Louisiana Tech University . These programs are designed to help users to become more aware and to better select Trenchless Technologies when installing, replacing or rehabilitating a pipes and manholes.

Background

Investments in infrastructure are mainly provided by the public sector and represent, together with the running cost of existing infrastructure, a significant proportion of public budgets. A challenge facing every state is maintaining its infrastructure in a good state of repair to support optimization of economic activities and meet relevant environmental regulations, while at the same time having sufficient funds available for supporting new growth.

However, reducing maintenance costs and improving sewer, water and gas systems' efficiency have always been challenges for municipalities and decision-makers due to the large number of factors involved (i.e. volume, velocity, temperature and chemical composition of the waste stream, burial depth, diameter, and material composition of the pipe; multiple failure modes/patterns). The traditional approach for rehabilitating an inadequate sewage, water or gas system is replacement using the cut-and-cover method. In congested and densely populated areas, performing such an operation would disrupt traffic and nearby businesses and result in annoyances (noise, dust, vibration) to the general public. Additional costs may be associated with the repair and re-pavement of the road surface or landscape features as well as accelerated deterioration of secondary roads due to detours and in some cases reduced road safety. In the past few decades new methods, namely Trenchless Technologies, have been introduced to the municipal marketplaces that are capable of rehabilitation, replacement and new installation of buried sewer, water, and gas pipes with minimal surface disruption and potentially, lower costs.

With this in mind the research team, along with its sponsors, set out to develop comprehensive, yet straightforward and easy to use interactive software for the evaluation and ranking of alternative construction methods that can be employed in the installation, rehabilitation or replacement of buried sewer and water pipes . The need for a computerized decision support system arose from the following reasons:

• Number of methods - there are 21 trenchless and 2 primary open-cut construction methods that can be employed for the installation of new pipes, 6 inline replacement methods, and over 30 trenchless methods as well as several open cut based methods for the rehabilitation of existing pipes.

• Complexity of analysis - each alternative construction method offer unique advantages and limitations; also, the decision making process involves a large number of parameters, some of which are interrelated.

• The rapid development of condition assessment, rehabilitation and replacement technologies - decision-makers that are not well acquainted with recent developments in the rapidly growing field of trenchless technology June 12, 2008ives that might accomplish the same task with less disruption and at lower costs.