CELEX: 51990PC0486
Language: en
Date: 1990-10-17
Title: PROPOSAL FOR A COUNCIL DIRECTIVE AMENDING DIRECTIVE 85/3/EEC ON THE WEIGHTS, DIMENSIONS AND CERTAIN TECHNICAL CHARACTERISTICS OF CERTAIN ROAD VEHICLES

No C 292/12                         Official Journal of the European Communities                            22. 11. 90
           Proposal for a Council Directive amending Directive 85/3/EEC on the weights, dimensions and
                               certain technical characteristics of certain road vehicles
                                                  COM(90) 486 final
                                  (Submitted by the Commission on 26 October 1990)
                                                     (90/C 292/11)
           THE COUNCIL OF THE EUROPEAN COMMUNITIES,
           Having regard to the Treaty establishing the European Economic Community, and in
           particular Article 75 thereof,
           Having regard to the proposal from the Commission,
           Having regard to the opinion of the European Parliament,
           Having regard to the opinion of the Economic and Social Committee,
           Whereas, in the light of decisions made at the adoption of Council Directive 89/338/EEC (x) it
           is necessary to give an objective technical definition to the equivalence of air suspension;
           Whereas, in order to mitigate the negative effect on the road pavement and on certain bridge
           structures of the 11,5 tonnes drive axle of heavy commercial vehicles, that drive axle should be
           fitted with twin tyres and air suspension or suspension considered to be equivalent,
           Whereas the increased benefit of twin tyres and air suspension or its equivalence should permit
           the use of the 11,5 tonne drive axle and whereas if the drive axle is not equipped with twin
           tyres and air suspension or its equivalent its maximum authorized weight should be limited to
            10,5 tonnes,
           Whereas measures to reduce the adverse effect of axle weight (both static and dynamic) on the
           road pavement and bridges should not prejudice the vehicle's safety, in particular its stability
           and braking characteristics, indeed these qualities should be enhanced,
           Whereas this proposal can be considered as the first step towards prescribing requirements for
           vehicle axles and axle groups that take full account of the need to mitigate as far as possible
           the negative effect of the total vehicle on road and bridge structures;
           Whereas Council Directive 85/3/EEC (2), as last amended by Directive 89/461/EEC (3),
           should be amended accordingly,
           (') OJ No L 142, 25. 5. 1989, p. 3.
           (2) OJ No L 2, 3. 1. 1985, p. 14.
           (3) OJ No L 226, 3. 8. 1989, p. 7.
 ---pagebreak--- 22. 11.90                            Official Journal of the European Communities                               N o C 292/13
          HAS ADOPTED THIS DIRECTIVE:
                                                         Article 1
          Directive 85/3/EEC is hereby amended as follows:
          1. The following third and fourth paragraphs are added to Article 4:
             '3.     For vehicles refered to in Annex I which are first put into circulation from January
             1993 the provisions of Article 3 (1) shall apply when the drive axle is at its maximum auth-
             orized weight of 11,5 tonnes and where it is equipped with twin tyres and air suspension or
             suspension recognized as being equivalent within the Community as defined in Annex III.
             4.    Where the drive axle of any vehicle referred to in the third paragraph is not equipped
             with twin tyres and air suspension or suspension recognized as being equivalent within the
             Community as defined in Annex III then the maximum authorized weight of that drive axle
             shall be limited to 10,5 tonnes.'
          2. Annex I is amended as follows:
             Paragraph 2.2.4.2:
             '2.2.4.2.   is greater than 1.8 m                   36 tonnes + 2 tonnes of margin when the
                                                                 MAW of the motor vehicle (18 tonnes) and
                                                                 the MAW of the tandem axle of the semi
                                                                 trailer (20 tonnes) are respected and the
                                                                 driving axle is fitted with twin tyres and air
                                                                 suspension or suspension recognized as
                                                                 being equivalent within the Community as
                                                                 defined in Annex III.'
             Paragraph 2.3.2:
             '2.3.2.     Three-axle motor vehicles                    25 tonnes,
                                                                     26 tonnes where the driving axle is fitted
                                                                     with twin tyres and air suspension
                                                                     or suspension recognized as being
                                                                     equivalent within the Community as de-
                                                                     fined in Annex III.'
             Paragraph 2.3.3:
             '2.3.3.     Four-axle motor vehicles with                32 tonnes where the driving axle is fitted
                         two steering axles                           with twin tyres and air suspension
                                                                      or suspension recognized as being
                                                                      equivalent within the Community as de-
                                                                      fined in Annex III.'
             Paragraph 3.5.3:
             '3.5.3.      1,3 m or greater but less than              18 tonnes
                          1,8 m (1,3 m < d < 1,8 m)                   19 tonnes where the driving axle is fitted
                                                                      with twin tyres and air suspension
                                                                      or suspension recognized as being
                                                                      equivalent within the Community as de-
                                                                      fined in Annex III.'
          3. A new Annex III is added as set out in the Annex hereto.
 ---pagebreak--- N o C 292/14                              Official J o u r n a l of the E u r o p e a n C o m m u n i t i e s             22. 11. 90
                                                                    Article   2
           1.      T h e M e m b e r States shall, after consultation with the C o m m i s s i o n , bring into force the
           laws, regulations and administrative provisions necessary to comply with this Directive n o t later
           t h a n 1 J a n u a r y 1993.
           W h e n M e m b e r States a d o p t these provisions, these shall contain a reference to this Directive or
           shall be accompanied by such reference at the time of their official publication. T h e p r o c e d u r e
           for such reference shall be a d o p t e d by M e m b e r States.
           2.       M e m b e r States shall forthwith c o m m u n i c a t e to the Commission the provisions of national
           law which they a d o p t in the field covered by this Directive.
                                                                    Article   3
           T h i s Directive is addressed to the M e m b e r States.
                                                                    ANNEX
                                                                   ANNEX      III
           Conditions relating to the use of the 11,5 tonne drive axle (or any drive axle with a maximum authorized
                                                         weight above 10,5 tonnes)
            1. Drive axles
                The drive axle at a maximum authorized weight above 10,5 tonnes shall be fitted with twin tyres and be
                supported by a suspension system as defined in paragraphs 3 and 4.
           2. Tyre contact pressure
                Tyre contact pressure must not be greater than 8 bars.
           3. Definition of air suspension
                A suspension system is considered to be air suspended if at least 75 % of the spring effect is caused by
                the air spring.
           4. Equivalence to air suspension
                A suspension recognized to be equivalent to air suspension must conform to the following:
                4.1. During free transient low frequency vertical oscillation of the sprung mass above a drive axle or
                     bogie, the measured frequency and damping with the suspension carrying its maximum load must
                     comply with the limits defined in paragraphs 4.2 to 4.5.
                4.2. Each axle must be fitted with hydraulic dampers. On tandem axle bogies the dampers must be
                     positioned to minimize the oscillation of the bogies.
                4.3. The mean damping ratio D must be more than 20 % of critical damping for the suspension in its
                     normal condition with hydraulic dampers in place and operating.
                4.4. The damping ratio d of the suspension with all hydraulic dampers removed or incapacitated must
                     be not more than 50 % of D.
 ---pagebreak--- 22. 11. 90                               Official J o u r n a l of the E u r o p e a n C o m m u n i t i e s           N o C 292/15
              4.5. The frequency of the sprung mass above the drive axle or bogie in a free transient vertical oscil-
                    lation must not be higher than 2,0 Hz.
              4.6. The definition of the frequency and damping of the suspension is given in paragraph 5 and the test
                    procedures for measuring the frequency and damping are laid down in paragraph 6.
           5. Definition of frequency and damping
              In this definition a sprung mass M kg above a drive axle or bogie is considered. The axle or bogie has a
              total vertical stiffness between the road surface and the sprung mass of k newtons/metre (N/m) and a
              total damping coefficient of C newtons per metre per second (N-s/m). The vertical displacement of the
              sprung mass is Z. The equation of motion for free oscillation of the sprung mass is
                                              d2 Z                     d Z
                                       M                     + C                      + kZ = 0
                                               dt2                      dt
              The frequency of oscillation of the sprung mass F rad/sec is
                                                               K                        C2
                                              1/               M        ~~             4M 7
              The damping is critical when C = Co, where
                                       Co   =    2   1/        KM
              The damping ratio as a fraction of critical is C/Co.
              During free transient oscillation of the sprung mass the vertical motion of the mass will follow a
              damped sinusoidal path (Figure 2). The frequency can be estimated by measuring the time for as many
              cyles of oscillation as can be observed. The damping can be estimated by measuring the heights of
              successive peaks of the oscillation in the same direction. If the peak amplitudes of the first and second
              cycles of the oscillation are Ai and A2, then the damping ratio D is:
                                                    C                     1                     Aj
                                      D    =                     =                    In
                                                    Co                  2 K                    A2
              In is the natural logarithm of the amplitude ratio.
           6. Test procedure
              To establish by test the damping ratio D, the damping ratio with hydraulic dampers removed, and the
              frequency F of the suspension the loaded vehicle should either:
              (a) be driven at slow speed (5 km/h ± 1 km/h) over an 80 mm step with the profile shown in Figure 1.
                   The transient oscillation to be analysed for frequency and damping occurs after the wheels on the
                   drive axle have left the step;
                   or
              (b) be pulled down by its chassis so that the drive axle load is 1,5 times its maximum static value. The
                   vehicle hold down is suddenly released and the subsequent oscillation analysed;
                   or
              (c) be pulled up by its chassis so that the sprung mass is lifted by 80 mm above the drive axle. The
                   vehicle hold up is suddenly dropped and the subsequent oscillation analysed.
 ---pagebreak--- N o C 292/16                          Official J o u r n a l of the E u r o p e a n C o m m u n i t i e s            22. 11. 90
             The vehicle should be instrumented with a vertical displacement transducer between drive axle and
             chassis, directly above the drive axle. From the trace the time interval between the first and second
             compression peaks can be measured to obtain the frequency F and the amplitude ratio to obtain the
             damping. For twin drive bogies, vertical displacement transducers should be fitted between each drive
             axle and the chassis directly above it.
                                                                Figure 1
                                                       Step for suspension tests
                                                                                                              10-20 mm radius
                                         Direction of travel
                                                                Figure 2
                                                   A damped transient response