Improving the stability of the roadbed
Abstract
Improving the stability of the roadbed
Incoming article date: 22.03.2022During the construction, overhaul and reconstruction of highways, various transport and technical and hydraulic structures, timely and effective drainage of ground water through the use of high-quality drainage systems is of paramount importance. It is well known that the main cause of deformation and destruction of the roadbed is both surface and ground water. It is necessary to ensure good filtration capacity, high water permeability, strength characteristics and reliability of the drainage system, thereby increasing the bearing capacity of the roadbed throughout the life cycle of the structure used. The authors of this article decided to set up an experimental section of the drainage system in the summer, during the period when the UGV is the lowest. A trench with the lowest permissible slope of water intake pipes is arranged primarily, depending on their diameter, they should be in the range from 0.001 (at d = 500 mm) to 0.007 (at d = 150 mm) and a depth of 40 cm below the UPG. The width of the trench is 45-50 cm larger than the diameter of the pipe. The bottom of the trench is leveled and compacted. After the trench is installed, a leveling layer of sand with a filtering capacity of at least 5 m / day is laid into it. and a thickness depending on the type of soil (loamy 15 cm, clay at least 20 cm), which is covered with a geotextile cloth so that the edges come out of the ditch with a sufficient margin for subsequent closure of the structure. The horizontal tubular drainage system should include inspection, drop-in and receiving wells. At the bottom of the trench, already with the geotextile laid, crushed stone of a fraction of 10-20 mm is filled in, with a layer thickness of 30 – 40 cm. Then the laying of drainage pipes begins, from the drainage well, in compliance with the slope. The next step in the installation of drainage pipes will be filling them with a layer of crushed stone, about 20 cm thick, and its subsequent sealing. After that, the structure is wrapped with geotextile cloths located on the surface with minimal overlap on each other, securing the joints with a rope or thin wire to prevent disclosure. The remaining part of the trench is filled with local soil with its layer-by-layer compaction.
Keywords: pipe filter, drainage system, non-woven geotextile, drainage pipe, filtration, water permeability, surface density, life cycle of the structure, ring stiffness