Economic analysis about the influence of the direct connection micropile-foundation on the underpinning project costs - Pellicer-Martínez, Francisco; Vicente S. Martínez Lirón; Alejandro M. Hernández Díaz; José A. López Juárez; Jorge Pérez Aracil (CMMost 2021: 6th International Conference on Mechanical Models in Structural Engineering, 2022)