https://www.homedepot.com/p/Construction-Select-4-in-x-12-in-x-16-ft-Ground-Contact-Hem-Fir-Pressure-Treated-Timber-10021209/100029018
4 x 12 x 16 Select Pressure-Treated Timber - This lumber meets the highest grading standards for strength and appearance, and is pressure treated for...
constructionselectxft
https://www.preprints.org/manuscript/201804.0149
In the extra-thick coal seams and multi-layered hard roofs, the longwall hydraulic support yielding, coal face spalling, strong deformations of goaf-side...
ground pressureoverburdenfailurebehaviourlongwall