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					         PPGS
N3/1: Durban - Pinetown
             PPGS
N2/25,26 DURBAN OUTER RING ROAD
                      PPGS
      N2/25,26 DURBAN OUTER RING ROAD

                 Pavement History
Constructed: 1978 (northern last 3 km 1990)

Pavement Structure:    40 mm            AS
                       125-145 mm       BS
                       150 mm           C2/C3
                       150 mm           C3/C4
                       150 mm           C4 SG
                       Subgrade         G7

Overlay 1990/93:       40 mm            AS
                       PPGS
        N2/25,26 DURBAN OUTER RING ROAD

                       Traffic


                    AADTT        AADT     ± Area m2
Section A (South)   4826         85 743   500 000
Section B (North)   1706         18 400   260 000
                                                       PPGS
               N2/25,26 DURBAN OUTER RING ROAD
                                  95th PERCENTILE PAVEMENT CONDITION PARAMETERS

                                               Initial rut   New rut (mm) – various lane          Remaining life (years) for
No        Km         Direction   Ymax ( m)   (mm) – slow                                  IRI   different traffic scenarios
                                                lane only
                                                             Rut (mm)           Lane              DBP             AASHTO
      17.2 – 18.15                                              16                2
     18.15 – 20.02                                              22                3
1                       N           122           12                                       3.2   19-28               13
     20.02 – 20.64                                              16                2
     20.64 – 22.18                                              12                1
      17.2 – 18.01                                              16                2
1    18.01 – 19.39      S           110            7             -                -        2.7   18-26               >20
     19.39 – 22.18                                              16                2
     22.18 – 27.49                                              21                2
2    27.49 – 28.04      N           118           16            12                1        3.1   17 – 26             11
     28.04 – 28.65                                              19                2
     22.18 – 26.94                                              16                2
2    26.94 – 27.68      S           108            9            11                1        3.2   17-25               11
     27.68 – 28.65                                              16                2
     28.65 – 29.95                                              19                2
3                       N           84            14                                       3.0   17 - 26             11
     29.95 – 30.8                                               13                1
3    28.65 – 30.8       S           206            8            16                2        3.5   10-16               11
       0.0 – 0.89                                               14                3
       0.89 – 1.25                                               7                2
4                       N           137           10                                       3.0   17 - 26              7
        1.25 – 3.3                                              13                3
         3.3 – 3.5                                               8                2
       0.0 – 2.06                                               10                3
4                       S           N/A            8                                       2.2    N/A                >20
       2.06 – 3.5                                                -                -
5       3.5 – 10.4      N           182            9            13                2        3.1   12-19               15
        3.5 – 10.4                                              12                2
5                       S           N/A            9                                       2.3    N/A                >20
        3.5 – 10.4                                               9                2
6      10.4 – 13.8      N           87             7            11                2        2.5    >20                >20
      10.4 – 11.44                                               9                2
6    11.44 – 12.06      S           69             5             8                1        2.1    >20                >20
      12.06 – 13.8                                              11                2
             PPGS
N2/25,26 DURBAN OUTER RING ROAD




      ROUND No 1
                     PPGS
N2/25,26 DURBAN OUTER RING ROAD


           Tender Closure – October 2002
Tenderer              PPGS             *Non PPGS /
                                        Alternative
   A                R26,5 m                   -
   B                R28,3 m                   -
   C                R74,3m                 R70,0 m*
                                           R71,8 m*
                                           R72,9 m
                                           R75,3 m
   D                   -                   R58,9 m*
                                           R60,8 m*
                                           R63,2 m*
          PPGS
SANRAL / SAFCEC WORKSHOP


     5 FEBRUARY 2003


     40 PARTICPANTS
                        PPGS Workshop

•   Experiences with PPGS
•   Risk sharing
•   Quality
•   Innovation and Product Certification
•   Tender Procedures
•   Procurement
•   Partnering and subcontracting
•   Performance guarantees
•   Scope of PPGS
•   Recommendations
                        PPGS Workshop

                      Experiences with PPGS
•   > 10 Projects to date. Generally successful
•   BOT projects ( a form of PPGS?) tend to have lighter
    pavement structures than conventional. Money/risk?
•   Whole life cost of PPGS = conventional projects. Could be
    less due to greater focus on quality and reduced cost
    during maintenance period?
•   In general, little innovation observed on PPGS projects
•   CAPSA 94 resolution: PPGS should be implemented
    incrementally
                        PPGS Workshop

                           Risk Sharing
•   Need to properly understand and quantify the risk profile.
    If known, more confidence to tender
•   Industry perception that only high risk projects go PPGS
    SANRAL approach – generally low risk (existing pavement
    condition)
•   Substantial number of variables may need to be controlled:
    difficult to quantify
                         PPGS Workshop

                              Quality
•   Contractor responsible for quality on conventional projects
    – more so on PPGS (incentive?)
•   Contractor be left to decide how to do the work and not be
    directed by the employer. Professional partner to offer
    him guidance
•   PPGS is all about building better quality into the works
•   Control of sub-contractors and suppliers!
•   ISO 9000 often a mere paper exercise?
•   Contractors tendered quality plans must be enforced
    during project
                        PPGS Workshop

           Innovation and Product Certification
•   Employers should not be too prescriptive and refrain from
    presenting benchmark designs, which could impede
    innovation
•   Rather provide employers cost estimate
•   Employers should refrain from specifying a product (e.g.
    single seal) as well as performance requirements?
•   Product certification increases employers confidence?
•   Although product certification is desirable, some problems
    at this stage (time /cost/market size)
                        PPGS Workshop

                       Tender Procedures
•   The purpose and objectives of any PPGS project must be
    made clear to tenderers
•   To date, insufficient time for tendering on PPGS projects
    (6 weeks minimum)
•   Need for a pre-site meeting to clarify technical issues?
•   Volume 6 contract document should include all relevant
    information in Detailed Design Report
•   Escalation and Rise and Fall on guarantee sum should either
    be part of risk (built in PPGS premium) or Contractor
    should specify and request in his tender
                       PPGS Workshop



                         Procurement
• Concern that PPGS not fully aligned with current
  procurement policies? Does not necessarily fall outside
  procurement directives but may have a cost premium
•   PPGS should be no exception to the promotion of capacity
    building, transformation and empowerment in the industry
                        PPGS Workshop



                 Partnering and subcontracting
• Good working relationship and partnerships are considered
  essential
•   Supplier to vet the application of his product?
•   Sub contractor/Suppliers to participate in supply of
    guarantees?
                      PPGS Workshop

                  Performance Guarantees
•   Based on previous experience, premiums for PPGS range
    between 3-4%
•   Size of premiums make PPGS a viable alternative to
    conventional?
•   Insurance companies partake in risk assessment
•   Reasonable performance criteria should be set over time.
    Employers do not expect a “new” road at end of guarantee
    period
•   Obtaining guarantees is no longer a problem ! May however
    be difficult if period exceeds 8 years?
                        PPGS Workshop

                         Scope of PPGS
•   May need to redefine PPGS level 2 e.g.
    Level 2A – limited to surfacings
    Level 2B – includes reworking of support layers (may
                require longer guarantee periods)




•   If risk profile is too high and cannot be adequately
    quantified, pricing of risk becomes impossible. Very long
    guarantee periods (20 years) not considered feasible
                        PPGS Workshop


                         Scope of PPGS
•   Consultants noted that pavement engineering is not an
    exact science and very little can be guaranteed (including
    traffic). Design engineers must however include design
    assumptions, which will be evaluated by employer
                        PPGS Workshop

                        Recommendations
•   PPGS requires a longer tender period
•   All available info must be supplied to contractors
•   All information should be supplied 2 weeks prior to site
    insp.
•   Technical meeting desirable before or during tender period
•   SANRAL to investigate accommodation of CPA & rise and
    fall
•   SANRAL should look at wider spread (low/high risk)
    projects
•   Further work needed to better understand and predict
    risks associated with PPGS projects
                    PPGS Workshop



                     General feeling


Contractors are generally supportive of PPGS (depending on
risks). Favours alternative products and quality conscious
contractors
             PPGS
N2/25,26 DURBAN OUTER RING ROAD



      ROUND No 2
                    PPGS
N2/25,26 DURBAN OUTER RING ROAD


           Tender closure – March 2003
Tenderer             PPGS                *Non PPGS /
                                          Alternative
   A               R17,6 m                    -
   B               R77,9 m                    -
   C               R124,9 m                R79,6   m
                                           R82,6   m
                                           R67,0   m
                                           R66,7   m
Estimate                                   R69,5 m
                    PPGS
Judges decision:
•   Is it a slip?
•   Is it a TKO?
•   Is it a KO?

				
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