Earth Bed

Earth Bed


a structure that serves as the foundation for the superstructure of a railroad track or the pavement of a road. The earth bed absorbs the load from the rails and crossties (sleepers), ballast, and rolling stock on a railroad and from the pavement and motor-vehicle traffic on a highway by distributing it uniformly over the underlying natural ground. An earth bed is one of the main elements of a road; its condition determines the good working condition of rail-road track and road pavement.

Railroad earth beds consist of embankments and cuts, as well as borrow pits, spoil banks, drainage devices (side ditches, troughs, catch drains, banquette cuts, and drains), and reinforcing and protective structures. The width of the main roadbed adopted in the USSR for single-track lines (on straight sections of track) is 7 m for lines of the first and second categories, 5.8 m for lines of the third category, and 5.5-5.8 m for lines of the fourth category. The width is correspondingly reduced to 6 and 5.2 m in rocky, largefragment, and sandy soils (except fine and silty sands). If a second track is planned, the distance between its axis and the edge of the bed is set at 3.5 m. On curved sections the width of the bed is increased by 0.1-0.5 m on the outer side, depending on the radius of the curve.

A highway roadbed is composed of the roadway, two shoulders, and a dividing strip or railings. The width of the roadbed is 27.5 m or more for roads of the first category, 15 m for roads of the second category, 12 m for roads of the third category, 10 m for roads of the fourth category, and 8 m for roads of the fifth category. The steepness of the embankment and excavation (cut) slopes depends on the soil characteristics; the geological, hydrographic, and climatic conditions of the locality; construction methods; embankment height; and excavation depth. Methods used to reinforce the banks of earthen roadbeds include the planting of perennial grasses, the laying of sod or flagstones, the planting of bushes, the use of fascine, and covering with built-up, cast, or reinforced concrete.

Earth beds are usually constructed by special mechanized groups or teams, which have such excavating and earthmoving machines as excavators, dump trucks, pull-type and motor scrapers, grader elevators, motor graders, screw-type planers, and machines for packing the soil of embankments and for finishing work.


Chernyshev, M. A. Vstroistvo, soderzhanie i remont puti, 2nd ed. Moscow, 1963.
StroiteVnye normy i pravila, part 2, sec. D, chapter 6: “Avtomobil’nye dorogi promyshlennykh predpriiatii.” Moscow, 1964.
References in periodicals archive ?
The construction works are executed according to a project prepared by the contractor and approved by the contracting authority and includes: - spoiling the existing road construction along its entire length and width, - dismantling existing concrete curbs, - the construction of the new road construction after coordination with the imp, - carrying out all necessary activities to ensure proper drainage of the roadway and the earth bed - drainage systems, Collector systems, Rainwater shafts, Inspection shafts, And so on.
Japan finds major rare earth bed in waters near easternmost island
Each class has its own raised earth bed to grow vegetables of its choice, some opting for pizza ingredients, others for potatoes or salad.
For the first time since it was created the road and a brick-built bridge over the River Medway are now visible above its cracked earth bed.
First, I led students in making a large-scale earth bed 10 x 13 (3 x 3.
People in the community will continue to watch the earth bed as it changes over time with the handmade paper dissolving into mulch and the flowers growing and blooming in the quilt pattern.
types of activities: - geodetic surveys of the existing terrain, - excavation work, - production of reinforced concrete drainage in detail, - sealing the earth bed, - strengthening the earth basis, - laying the crushed stone, - laying of 20 cm thick concrete pavement with double reinforced mesh no 10 on a 20/20 cm carriage, concrete b 40, sulphate-resistant, shaped in rectangular fields enclosed by joints.
For the container chambers a large earth bed is provided.
Exarch Joseph Borovo Municipality - construction activities include the following works: Excavation of earth bed of pavement; Mound of earth bed of pavement; Excavation for single foundations under playground equipment; Loading and transportation of waste by truck; Delivery, installation and transportation of sand under pavement and others.
Tenders are invited for Supply & making of earth bed & copper plate earthings for replacement of 2 x 3 kw fm tr by 5 / 6 kw fm tr at all india radio, ddk site, ajinkyatara, satara ( m.

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