SLIPPERINESS STUDIES OF WET ASPHALT PAVEMENTS IN ISRAEL. FULL-SCALE EXPERIMENT WITH SKID-RESISTANT SURFACINGS

A full-scale experiment with skid-resistant surfacings was made in the years 1972-1979 on a roadway of a divided highway, carrying nearly 2000 commercial vehicles per day on the outer lane and nearly 500 on the inner lane. The experiment consisted of 23 short sections of surfacings, of various textures and compositions. The aggregates used in the mixtures were dolomite, basalt, diorite, quartzite and calcite-cemented sandstone. The object of the experiment was to examine and compare the skid-resistance and general behaviour of the surfacings over a prolonged period of time. This report gives the results of the experiment based on skid-resistance measurements and visual assessments of the surfacings' condition, carried out periodically during 5 to 7 years of service. The main findings are: the sn-speed gradient in the range of 40-50 mph for dolomite aggregate, bituminous-concrete surfacings, used as a standard wearing course on all inter-urban roads in Israel, was found not to exceed 0.3. Based on this gradient and on HRB recommendation, the minimum sn40 requirement for highway sections with normal geometrical conditions is determined. The skid-resistance of bituminous-concrete surfacings, made with dolomite aggregate, decreased within one year of service below the recommended minimum level, under a traffic volume of nearly 2000 commercial vehicles per day. It was found that an improvement in skid-resistance may be obtained by partial replacement of the dolomite coarse fraction with a non-carbonate aggregate of a higher psv (such as basalt). Deep-textured, dense gap-graded basalt mix surfacings were found to be best on the basis of combined skid-resistance - durability criteria. Basalt bituminous-concrete was determined as second best. (Author/TRRL)

• Corporate Authors:

  Ministry of Construction and Housing

  Division of Highways, POB, 55 Ben-Zvi Road
  Tel Aviv,   Israel 
• Authors:
  • Nedavia, D
• Publication Date: 1980-8

Language

• Hebrew

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: 85 p.

Subject/Index Terms

• TRT Terms: Aggregates; Asphalt concrete; Asphalt pavements; Basalt; Calcites; Commercial vehicles; Dolomite; Durability; Moisture content; Motor vehicles; Pavements; Polished stone value test; Quartzite; Sandstones; Skid resistance tests; Skidding; Slipperiness; Speed; Surfacing; Surveying; Texture; Traffic speed; Wearing course (Pavements)
• Uncontrolled Terms: Skid number; Visual surveys; Wet conditions
• ITRD Terms: 4183: Basalt; 4967: Bituminous mixture; 5460: Coefficient of friction; 4191: Dolomite; 5910: Durability; 388: Inter urban; 8050: Israel; 6136: Measurement; 3822: Polishing; 4110: Porphyry; 4102: Quartzite; 4104: Sandstone; 3031: Skid resistance; 5408: Speed; 2972: Surfacing; 6255: Test; 671: Traffic flow; 2980: Wearing course; 3015: Wet road
• Subject Areas: Geotechnology; Highways; Pavements; I23: Properties of Road Surfaces;

Filing Info

• Accession Number: 00341025
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Report/Paper Numbers: SR-46 Monograph
• Files: ITRD, TRIS, ATRI
• Created Date: Oct 28 1981 12:00AM