Design and operational considerations to accommodate long combination vehicles and log haul trucks on rural highways in Alberta, Canada

The purpose of this paper is to outline the geometric design features that have been developed to accommodate Long Combination Vehicles (LCVs) and log haul trucks on rural highways in Alberta, Canada. Vehicles longer than 25 m are referred to as LCVs and include the following vehicles: Triple Trailer combinations, 35 m in length; Rocky Mountain Doubles, 31 m in length; log haul trucks which can be up to 30.5 m in length, with a 9 m overhang and Tumpike Doubles, 38 m in length. The paper presents the vehicle dimensions, swept path, and off­ tracking characteristics of each vehicle type. Geometric design features include intersections, ramps and centre­ line spacing on two-lane highways. The paper also presents the criteria used to develop the LCV and log haul truck route networks for the province. The movement of over-dimensional equipment, machinery and pre­ assembled components is accommodated on the high-wide-load (HWL) corridor. This 2100 km HWL corridor allows loads up to 9 m high and weights from 122 tonnes in the summer and 177 tonnes in the winter. Weights as high as 380 tonnes may be conveyed on condition that the size and space requirements of undercarriage wheel assemblies are met for critical bridge structures.