摘要: |
Horizontal Directional Drilling (HDD) has become one of the fastest-growing trenchless technology construction methods for the installation of underground pipelines and conduits. According to the board of directors of the Ohio Horizontal Directional Drilling Association (OHDDA), there are many HDD specifications employed in Ohio, and these specifications vary significantly in their content and requirements. Consequently, inferior products may have been installed, unnecessary risks may have been taken, and the competition among contractors may have been compromised. Therefore, a HDD specification that provides for high quality installations, allocates risks appropriately, and ensures correct design and installation of product pipes without damaging the roadway is needed. The proposed draft was based on comparison of more than 12 existing HDD specifications with the HDD Good Practice Guidelines and the collective input from professional partners representing the interest of the various entities involved in a typical HDD project. The research team along with the professional partners proposed draft specification for pressurized applications with pipe diameters in the range of 4 inches (10 cm) to 24 inches (60 cm). Installations outside this range of pipe sizes and gravity installations are beyond the scope of the specification. The implementation plan for the draft specification includes ODOT review to ensure it does not conflict with other ODOT specifications, ODOT evaluation of the proposed specification through use on an actual project, feedback from the larger interest groups across the state of Ohio, and update as needed. |