Abstract: The invention concerns a novel road structure whose bearing part on top of the ground comprises three successive layers of bituminous material bonded with one another, namely: a base layer which rests on the ground with optional insertion of a forming layer of thickness H.sub.i such that: 4 cm.ltoreq.H.sub.i .ltoreq.10 cm, and of elastic modulus: E.sub.i ; a median layer of thickness H.sub.m such that: 4 cm.ltoreq.H.sub.m .ltoreq.20 cm, and of elastic modulus E.sub.m such that: 2000 MPa<E.sub.m <8000 MPa; and a top layer of thickness H.sub.s such that: 4 cm.ltoreq.H.sub.s .ltoreq.10 cm, and of elastic modulus E.sub.s, such that elastic moduli of said layers comply with inequality relationships (a) and (b).

Abstract: This invention relates to a process for measuring the dynamic load exerted on a highway by the axles of the vehicles circulating thereon. Two piezo-electric cables sensitive to the pressure of the axles, furnish, upon passage thereof, a weight information pulse and a speed information pulse, respectively. Signals representing respectively the area of the pulse and the duration of the time gap separating the pulses, are applied to a divider which effects the quotient thereof and furnishes a signal representing the dynamic load.