CROSSFALL IN DESIGN OF TWO-LANE ROADS /IN FINNISH/

AFTER REVIEWING CROSSFALL SPECIFICATIONS IN DIFFERENT COUNTRIES, THE AUTHOR OUTLINES CROSSFALL DESIGN SPECIFICATIONS AS DRAWN UP IN NEW 1970 FINNISH STANDARD SPECIFICATIONS FOR ALIGNMENT DESIGN. AT THE MOMENT, THE CROSSFALL OF NEW TWO-LANE ROADS IS MOST FREQUENTLY THE MINIMUM REQUIRED FOR DRAINAGE. LARGER CROSSFALL VALUES ARE CONSIDERED ONLY IN EXCEPTIONAL CASES. RESULTS ARE GIVEN OF A SURVEY OF THE CROSSFALL OF 36 HIGHWAYS IN FINLAND. IT WAS FOUND THAT, ON GRAVEL ROADS, THE CROSSFALL NEVER EXCEEDED THE MINIMUM VALUE OF 5 PER CENT; THE MINIMUM CROSSFALL OF OIL GRAVEL ROADS WAS 4 PER CENT; 2.5 PER CENT WAS THE CROSSFALL NORMALLY FOUND FOR ASPHALT SURFACINGS. /RRL/