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Collar Suitability and Joint Deflection for MTBM Tunnelling

Appropriate jacking pipe collar selection can significantly influence the outcome and success of a microtunnelling project. Significant forces and loadings are experienced at the joints along a pipeline during installation which are subsequently experienced by the jacking pipe collar. Poor collar selection can lead to…

Condition assessment and rehabilitation of deteriorated buried pressure water pipes using MPEP

Assessing the levels of deterioration of buried pipelines is a significant asset management problem for most water utilities. The lack of asset condition information, particularly for old reticulation mains, compounds this problem, forcing utilities to adopt a reactive maintenance approach for their ageing assets. We…

Condition Assessment Outputs - What Do They Mean

Condition assessment of pressure water and sewer mains has become increasingly important over the past 20 years. Nowadays, there are several service providers offering a range of technologies, with varying outputs. This paper discusses some of the outcomes derived from a range of technologies, including acoustic…

Design of Enveloper Pipe Installations and To Grout or Not to Grout

The design requirements of enveloper pipe installations, or what is sometimes called a “pipe in a pipe”, often causes confusion among designers, installers, and asset owners alike. Often the design intent or purpose of the enveloper is not understood and there is confusion as to whether it is part of the temporary or…

Direct Pipe Down Under – Recent Success and Opportunities

Direct Pipe® (DP) was first introduced to the world in late 2007 with a 464m crossing beneath the Rhine River. Although still considered a new technology, as of March 2021, over 160 DP crossings have been completed globally with the popularity, and range of applications, growing rapidly since 2015. But what is Direct…

Direct Pipe in Three Case Histories- Overcoming Challenging Ground and Site Conditions

Direct Pipe® (DP) is a relatively new trenchless technology by which a steel pipe is installed in compression through curves and sometimes tangent sections. The ground in the heading of the pipe is excavated through conventional microtunneling methods while a Pipe Thruster machine provides the motive force. Once the…

Effects of temperature on material properties in spray and cured-in- place-pipe liners

Temperature plays a vital role in estimating the long-term properties of spray and CIPP liners, which are examined for relining deteriorated water pipes. Temperature variation in pipelines should be known prior to installation of any polymer-based pipe or liner. This ensures that long-term properties can be assessed…

End-to-end Pipeline Asset Management

Evaluation of One-Part Geopolymer Mortars as Protective Sewer Coating for Sewer Assets

This study evaluated the suitability of various commercially available geopolymer mortars (GP) for application in a sewer environment. Corrosion of one-part geopolymer mortars was compared with commercially available calcium aluminate cement through a series of accelerated corrosion and field tests. Accelerated…

Fibreglass Future – GRP Maintenance Structures on Large Gravity Sewers

Maintenance structures (or “manholes”) play an essential role in helping keep sewerage systems running. They enable the owner of the sewer to access, inspect and maintain a sewer throughout its asset life. Over the past 10 years, Melbourne water retailer Yarra Valley Water has embraced the use of glass-reinforced…

GeoKrete – A Geopolymer Pipe Rehabilitation System

GeoKrete is a geopolymer mortar liner for raw, storm and wastewater infrastructure rehabilitation. For rehabilitation of existing aged assets that have reached, or are nearing end of design life, it is an alternative that can provide a far more cost effective solution than complete replacement. AquaMetro has partnered…

Geology and Trenchless Technology

Even though there are significant benefits in utilising Trenchless Technology for the installation of new pipelines it brings its own set of challenges and risks that need to be appropriately managed for a successful outcome. One of the major risks with the use of any trenchless technology is the geology. To be able…

Hawthorn Main Sewer Rehabilitation

Innovation in trenchless rehabilitation of potable water lines - SAERTEX-LINER H2O

In 2019, SAERTEX multiCom was awarded with the ISTT NO-Dig Innovation award in the category of “UV curable GRP Liner for the trenchless rehabilitation of potable water lines” for their SAERTEX-LINER® H O. 2 This product, made in germany, is produced by SAERTEX multiCom GmbH a manufacturer of UV-cured…

Management of AC Pipes Now and Into the Future

Abstracts should be limited to 250 words maximum. Water Services Association of Australia (WSAA) commenced investigation of issues associated with Asbestos Cement (AC) pipes in the 2010/2011 WSAA Asset Management Program. Stage 1 (2013) quantified the length of inservice AC water mains at 40,000km costing between $8.9…

Minimum Performance Requirements of HDPE Pressure Pipes

Product and installation standards for HDPE pressure pipes have been established to ensure a target design life of at least 50 years under typical application conditions. It is essential that all actors involved in pipe value chain have a basic understanding of the minimum performance requirements listed in the…

Miracles of St Marys Bay Water Quality Improvement Project

In January 2020, McConnell Dowell Constructors (MCD) commenced the St Mary’s Bay Water Quality Improvement Project on behalf of Auckland Council Healthy Waters (ACHW). The project involved the construction of 1,125m of 1.8m ID storage tunnel, which was designed to intercept 3 existing Combined Sewer Outfalls. These…

Mountain Highway AC Water Main Renewal – Demonstration of a New Trenchless Alternative

Like Water Utilities throughout Australia, South East Water in Victoria has asbestos cement water mains in its distribution network that are reaching the end of their service life. South East Water’s 1,600 kilometres of AC mains were mostly laid in the 1950’s and 1960s, and like other Water Utilities, were mostly in…

Northern Interceptor Pipeline Project

The amount of wastewater being collected and treated has increased significantly as Auckland’s north-west residential regions have expanded. To cater for this future growth in Auckland and free up exiting Wastewater Treatment Plants, the NZ$108 million Northern Interceptor wastewater pipeline was proposed in order to…

Performance of cured-in-place-pipe lined cast iron pipes with circumferential defects under internal pressure

Circumferential defects may exist in deteriorated cast iron pipes before or after lining with cured-inplace-pipe (CIPP) liners. These defects may be in the form of gaps or failed joints and they may significantly influence the performance of the lined pipes under service conditions. However, limited research was found…

Pipe Jacking innovations for E-Power Pipe and small diameter Direct Pipe

Shaft Construction

Abstracts should be limited to 250 words maximum. Shaft construction Ground conditions Risk management Temporary to permanent works Shafts are needed on most trenchless construction projects, and they need to be treated with the same level of attention as other parts of the project. Shafts can be a major expense and…

Smart Linings for Pipe and Infrastructure

The Smart Linings for Pipe and Infrastructure Project researched the effectiveness of pipeline liners focusing on four product categories: cured-in-place pipe liners and polymeric spray liners for water mains, and calcium aluminate cement mortars and alkalai activated binders (including geopolymer cement mortars) for…

Specification: Design for Structural Renovation of Pipelines by Internal Lining