FROST PROTECTION OF ROADS AFTER CLEARANCE ENLARGING
Frost problems or problems related to the bearing capacity of the insulating material used must be considered in studies of the problems connected with the enlarging of the vertical free space (clearance) under railway bridges. The possible methods of protecting footing and roadway against frost heaving are excavation of the frost active material, frost heaving soils, and refilling with inactive, and thermal insulation. The principal requirement of the material used (besides good insulation) should be durability. Commercially available insulating materials such as mineral wool, foam plastics, HD-insulation and nature products (slags, gravel, peat and bark) are briefly reviewed. The materials presently used in Sweden are foam plastics, expanded clay and HD-insulation. The foam plastics are characterized by a high and even density. They have very low water absorption and the types used are practically non-plastic at the stresses they are subject to. HD-insulation consists of crushed stone which has all voids filled with an insulating material, which may consist of granulated mineral wool, foam plastic or urethane foam. The frost protection or insulation may be applied as a screen around the footing or as a collar extending from the footing with the newly exposed part of the footing covered with some insulating material. This material may consist of foam plastic or mineral wool as it will not be subjected to any traffic load. Between the foundations however, the road-bed must be protected in the conventional way by application of some frost protection method. It is important that the excavation is not carried deeper than necessary, especially if the soil can give rise to settlements or movement of the foundations.
- This paper was presented during the Symposium on Frost Action on Roads held in Oslo, Norway, 1-3 October, 1973.
Organisation for Economic Co-operation and Development (OECD)2, rue André Pascal
Paris, France 75775 Paris Cedex 16
- Jerbo, A
- This paper was presented during the Symposium on Frost Action on Roads.
- Location: Oslo , Norway
- Date: 1973-10-1 to 1973-10-3
- Publication Date: 1973
- Features: Figures; Photos;
- Pagination: p. 405-416
- Volume: 2
- TRT Terms: Car clearances (Railroads); Crushed rock; Density; Durability; Electric insulating materials; Excavations; Fibers; Footings; Frost heaving; Frost protection; Insulating materials; Minerals; Plastic foams; Railroad bridges; Subgrade (Pavements); Surface course (Pavements); Water
- Old TRIS Terms: Beds; Clearances; Frost heave; Mineral wool
- ITRD Terms: 6758: Absorption; 3455: Bridge; 5906: Conductivity (heat); 4173: Crushed stone; 5910: Durability; 4502: Expanded material; 3377: Foundation; 2585: Frost; 4575: Gravel; 6743: Heat; 6489: Height; 6914: Insulation; 9048: Modification; 5483: Movement; 2955: Pavement; 4349: Peat; 6285: Penetration; 4561: Slag; 5933: Thickness; 4355: Water; 4506: Wood (mater)
- Subject Areas: Geotechnology; Highways;
- Accession Number: 00260458
- Record Type: Publication
- Source Agency: Transport and Road Research Laboratory (TRRL)
- Report/Paper Numbers: Conf Paper
- Files: ITRD, TRIS
- Created Date: Oct 11 1975 12:00AM