Marshall Stability And Compaction Astm

Originally
developed by Bruce Marshall, a highway engineer in U.S.A later on
standardised by ASTM. Generally the test is applicable to hot mix
designs using bitumen and aggregates upto a maximum size of 25 mm.

 

In this method the resistance to plastic deformation of cylindrical
specimen of bituminous mixture is measured when the same is loaded
at periphery at 5 cm per min. This test procedure is used in designing
and evaluating bituminous paving mixes. The test procedure is
extensively used in routine test programmes for paving jobs There are
two major features of the Marshall method of designing mixes namely.
 


[A]. Density  voids analysis.

[B]. Stability  flow tests.


 

The marshall stability of mix is defined as a maximum load carried by a
compacted specimen at a standard test temperature of 60 deg.C. The flow
value is deformation the marshall test specimen under goes during the
loading upto the maximum load, in 0.25 mm units. In this test and
attempt is made to determine optimum binder content for the type of
aggregate mix and traffic intensity.

 

The apparatus consists of: 1. A loading unit motorized, capacity 5000
kg with two telescopic pillars and an adjustable cross head Limit
switches are fitted inside to control upward or downward movement of the
pillars. On  off reversing switch and indicator lamps are on the front
side while a hand wheel to manually move the pillars minute operated
on 230 Volts A.C.
 


[A]. 1 No. Compaction pedestal with specimen mould holder

[B]. 2 Nos. Compaction Rammers, 4.5 kg weight and free fall 45.7 cm.

[C]. 1 No. Breaking head assembly with provision to fix flow meter

[D]. 3 No. Specimen mould 10.16 cm I.D. x 7.6 cm high with base plate and
        extension collar

[E]. 1 No. Kit for specimen extraction, consists of one each load transfer bar,
        steel ball, specimen exacting plate.

[F]. Flow meter (dial gauge) grauated 0.01 mm x 25 mm travel

[G]. Fitted with a stem brake unit to indicate maximum deflection Complete as
        above.


 

Accessories :-

 

High sensitivity proving Ring 2500 kg capacity fitted with 0.002 mm dial
gauge and our own test certificate. Complete in a nice wooden carrying
case.