Stone Mastic Asphalt

Course feedbackCourse feedback

Specification updateSpecification updateRob VosMartin van de VenDennis Rossmann

DiscussionDiscussionExpanded panel

SMA

you&

me

BE

FO

RE

BE

FO

RE

Performance of some Performance of some SMA says we areSMA says we are

SMA - why a course?

hbasically a technology transfer from Europe

hnot only one European approach

hincreased interest locally

hstart-up problems

hsome lack of understanding of basics

hneed to fix the platform of knowledge

Usage of SMA’s in Europe

Country Total Area (106m2) % 1996

Denmark 14 1.1Germany >100 8Netherlands 32 8Norway 12 3Poland 12Spain (BBM) 69Sweden 50 18

Equates to > 27 000 km of single lane roads

SMA’s functional surfacecharacteristics

hgood skid resistance (safety)

han even surface (driver comfort)

hlow noise (environmental &

comfort)

hdurability - rut free (pavement performance)

himproved visibility (safety)

Three day SMA course

SMA course at Stellenbosch

hIngeborg Schröder - BP GermanyhHigh local inputh46 delegates

hclient bodieshsuppliershconsultantshcontractorshstudents

What is a real SMA ?

according to Draccording to Dr Zichner Zichner 1960’s 1960’s

hself supporting stone skeleton

hbitumen rich mastic (“glue”)

hlow voids content (impermeable)

hefficient stabilisation of the mastichduring transport, constructionhprevent segregation

Course contents

hFunctional / structural requirements of surfacings

hSMA mix design - spatial approach

hProduction, transport and construction

hProblems and failures

hLocal experience

hCost benefit

SMA problem areas

hmix designhaggregrate requirementshspecification status and developmentshsmaller window for manufacture and

constructionhtighter quality control

So where to with SMA’s

hstandardise the design approachhallow for changes to the current specificationhdevelop manufacture and placing guidelineshget ASPASA together in getting SMA’s to

work in SA