Influence of Horizontal Directional Drilling on Mechanical Properties of Airfield Pavements: An Integrated Study Based on Finite Element Modeling and Field Tests

This study explores the structural safety, mechanical response and optimal construction parameters of the Horizontal Directional Drilling (HDD) technology applied in airport rigid pavements novelly for navigation lighting renovation. This study adopts a combined research method of three-dimensional finite element modeling (FEM) and field tests (full-scale 4C and 4E class airport runway sections). The reliability of the model is verified by the measured data using a Heavy Weight Deflectometer (HWD). The effects of drilling depth, drilling position and typical aircraft loads on the stress and deformation at the bottom of the pavement slab are systematically analyzed. Then, drilling, grouting and non-destructive testing are carried out in the field full-scale test section to investigate the change in pavement bearing capacities. The results show that minimized influence on the mechanical properties of the pavement can be achieved by using 15 cm drilling depths at either slab center or joints. The pavement stiffness slightly decreases by a maximum of 18.9% after drilling. According to the field grouting test, the Impulse Stiffness Modulus (ISM) of most measuring points can be recovered to the original level before drilling. The use of a 10 cm diameter HDD driller meets the structural safety requirements of airport pavements. The HDD technology induces minimized pavement damage and influence on the bearing capacity of the airport runway structure compared with traditional construction technologies, highlighting its advantages in airfield navigation lighting renovations.