DRAINAGE SYSTEM FOR STABILISING THE ROADWAY ON THAWED SOFT SOILS Russian patent published in 2021 - IPC E01F5/00 E02B11/00 E02D17/20 

FIELD: construction of roads.

SUBSTANCE: invention relates to the field of construction of earthworks in complicated natural and climatic and engineering and geological conditions. The drainage system for stabilising the roadway on thawed soft soils comprises an upper and a lower longitudinal trenches and a waterproof screen. The trenches are made along the subgrade outside of the drained area. The upper and lower longitudinal trenches are filled with coarse-pored fractional drainage soil. The upper longitudinal trench is located directly behind the lower longitudinal trench higher uphill from the high part of the relief, forming a single stepped trench. The waterproof screen is laid on the side stepped face of the single trench, wherein a reinforcing screen is laid along the entire perimeter of the single stepped trench on top of said screen. The coarse-pored fractional drainage soil of the upper longitudinal trench is enveloped in a reinforcing screen, forming a drain. The upper longitudinal trench is made in the upper part of the seasonal thawing layer. The lower longitudinal trench is made to the full depth of the seasonal thawing layer and is overlapped with a heat insulation screen at the level of the step of the single stepped trench, wherein a waterproof layer is laid above said screen to the level of relief of the drained area. On the low side, additionally, in the near-bottom zone of the subgrade, a heat insulation screen is laid under a waterproof layer on the daylight surface. The waterproof layers on both sides of the roadway constitute dewatering berms made of clay soils.

EFFECT: increase in the maintenance-free service life of the drainage system until the time of planned re-equipment of the roadbed.

1 cl, 1 dwg