Comparative Analysis of Physical and Strength Properties of Various Aggregate sources in Pakistan

Abstract

Because of various mountain ranges of aggregate, Pakistan has a large aggregate potential. However, due to a lack of study in this field, the characteristics of these aggregates have yet to be investigated. Since the 1960s, Margalla crush has been widely utilized in road construction and building construction and is regarded as a standard aggregate source for road development in the federal and Punjab areas. As a result of the widespread use of Margalla in road and building construction, two more sources, Swabi and Hattar have been included in this research to determine the physical and strength attributes of these sources. Margalla crush qualities are used as a reference to examine the acceptability of aggregate samples gathered from other probable sources in this investigation. In this research, three sources are chosen and various physical tests including aggregate impact test, aggregate crushing test, elongation and flakiness test, Los Angeles abrasion test, aggregate absorption and specific gravity test are performed in laboratory to evaluate the physical strength of these sample. To assess their strength, density –voids analysis and the stability – flow, Marshall Mix Design is utilized. The rutting value is evaluated by utilizing the gyratory compaction test. Resilient modulus is also calculated by using the Universal Testing Machine (UTM) test. At the end, a comparison between different sources aggregate is also developed. The result represents that the aggregate impact values of Hattar and Swabi aggregates are 7.3% and 15.98% weaker than the Margalla source. All impact values lie under the standard specifications. The specific gravity of Hattar source for fine and coarse aggregates are 3.11% and 2.69% lesser than Maraglla source respectively. The specific gravity of Swabi source for fine and coarse aggregates are 4.7% and 3.48% weaker than Margalla source aggregates respectively, which represents that Margalla source has higher strength as compared to the other two aggregate sources. The Marshall stability of all sources are above 8KN which is in standard specifications. So, all three aggregates can be used in road construction. The stability of Hattar and Swabi source is 1.91% and 17.48% lesser than the Margalla source but good enough to be used in HMA construction. The flow (Deformation) of Hattar and Swabi sources are 13.33% and 37.68% higher than Margalla source, respectively. The flow of Swabi source is much higher as compared to the other two sources. However, all mixtures met the specification for roads. Resistance to permanent deformation of Hattar and Swabi aggregate is 28.94% and 17.09% less than the Margalla source.

All values are much less than standard value of 12.5mm. No sample fails in Rutting. So, all three aggregates can be used in road construction. The Resilient Modulus of Hattar source is 6.27% better than the Margalla aggregate source while MR of Swabi source is 10.32% lesser than the Margalla Source. However, all mixtures met the specification for roads. In comparison to Margalla aggregates, aggregates generated from Hattar and Swabi quarries are appropriate for road construction according to the analysis. If these quarries are developed, they would be able to generate plenty of long-lasting aggregates for Pakistan's Khyber Pakhtunkhwa and northern Punjab regions by reducing the load on Margalla source.