BACKGROUND
State departments of transportation (DOTs) are increasingly using trenchless strategies to rehabilitate and repair aging infrastructure within urbanized areas. Performing pipe repairs to existing systems, as compared to pipe replacement, significantly reduces the construction time and maintenance of traffic operations and roadway reconstruction. This provides increased public safety and cost savings to the state DOTs. One of the most common pipe rehabilitation methods is cured in-place pipe (CIPP) liners. CIPP liners are a trenchless technology that provides a method to structurally rehabilitate existing pipes and conduits with minimal impact to the traveling public. The liner consists of a resin-impregnated material that is inserted into the existing damaged host pipe.
Currently, there is insufficient information available to ensure the CIPP liner possesses the properties and durability of the expected life span of this repair strategy. Pipe owners and CIPP contractors need design guide and testing standards for CIPP pipe rehabilitation repair.
OBJECTIVES
The objectives of this research was to develop (1) an AASHTO guide for design and installation of CIPP liners for structural rehabilitation of existing pipelines and conduits including design examples to demonstrate the application of the guide and (2) an AASHTO standard practice for test methods for CIPP liner technology. The AASHTO guide for design of CIPP liners will be based on the Load and Resistance Factor Design (LRFD) method.
At the minimum, the AASHTO standard practice for CIPP liner technology will include:
- a laboratory test method to verify the proposed structural capacity of rehabilitated conduits using CIPP liner technology,
- an accelerated laboratory test method to predict liner service life, and
- a laboratory test method for the different materials for liner and resin, and curing methods.
STATUS: The remaining tasks have been transferred to a new project that is pending.
