An Experimental Approach to Evaluate the Resistance of Gas Pipeline to Dent and Gouge Damage by an Excavator

An experimental methodology for the evaluation of the resistance of gas pipeline with regard to the third part aggression by an excavator is presented. The essential tool used is a new full-scale facility specifically designed to be able to reproduce, in full-scale conditions, the external mechanical damage caused by concentrated loads, both static and dynamic, due to an excavator acting on pipelines for gas transportation. The main characteristics of the facility are: • computer controlled with the possibility to insert stiffness feedback control to simulate different excavators; • trajectory in vertical plane defined by the user via computer; • trajectory in transverse plane defined by the user using springs with stiffness simulating different excavators; • use of real excavators tooth as aggression tool; • pressurised or unpressurised test pipe. The aim of the presented experimental methodology is to demonstrate the capability to reproduce “real” excavator damage under controlled laboratory conditions starting from few, simple and basic information such as excavator type and characteristics, tool type, digging modality and relative position between excavator and pipe.