Marshall Stability Test Apparatus

Marshall Stability Test Apparatus

---

Marshal test is extensively used in routine test programs for the paving jobs. The stability of the mix is defined as a maximum load carried by a compacted specimen at a standard test temperature of 600 °C. The flow is measured as the deformation in units of 0.25 mm between no load and maximum load carried by the specimen during stability test (flow value may also be measured by deformation units of 0.1 mm). This test attempts to get the optimum binder content for the aggregate mix type and traffic intensity. This is the test which helps us to draw Marshall Stability vs. % bitumen.

Features:-
A loading unit motorized capacity 5000kgf 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 is on the right. The load frame has fixed speed of 5.08cm per minute. Operated on 230 Volts A.C
1 No. Compaction pedal with specimen mould holder.
2 Nos. Compaction Rammers, 4.5kg weight and free fall 45.7cm
1 No. Breaking head assembly with provision to fix flow meter.
3 Nos. Specimen mould 10.16cm I.D. x 7.6cm high with base plate and extension collar.
1 No. Kit for specimen extraction consists of one each load transfer bar, steel ball, specimen extracting plate.

Technical Specification:-
Heat the weighed aggregates and the bitumen separately up to 170°C and 163°C respectively.
Mix them thoroughly, transfer the mixed material to the compaction mould arranged on the compaction pedestal.
Give 75 blows on the top side of the specimen mix with a standard hammer (45cm, 4.86kg). Reverse the specimen and give 75 blows again. Take the mould with the specimen and cool it for a few minutes.
Remove the specimen from the mould by gentle pushing. Mark the specimen and cure it at room temperature, overnight.
A series of specimens are prepared by a similar method with varying quantities of bitumen content, with an increment of 0.5% (3 specimens) or 1 bitumen content
Before testing of the mould, keeps the mould in the water bath having a temperature of 60°C for half an hour.
Check the stability of the mould on the Marshall Stability apparatus.

Accessories:-
Integral type Proving Ring capacity 3000 kgs
A dial gauge 0.01 x 25mm
Universal Water Bath S.S. with false bottom and pyramid shaped lid to accommodates 3 Nos. marshal specimen
Thermometer 0 – 250ºC x 1ºC