Fig 4 - uploaded by Shahid Naseem
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Types of gradation curves and curve of the study area, based on average grain size. Shaded area specifies upper and lower limits of coarse aggregate
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Properties of coarse aggregate of carbonate rocks of Malikhore Formation of Jurassic age of districts Lasbela and Khuzdar, SE Balochistan were investigated. Bulk specific gravity (SSD), water absorption, sieve analysis, Los Angeles abrasion test, unconfined compressive strength, soundness, silica alkali reactivity, clay lump and friable particles,...
Contexts in source publication
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... sieve is raised to the nth power (usually taken as 0.45) and convenient for determining the maximum density line and adjusting gradation [18]. In the graph, size of the aggregate is plotted on x-axis in descending order; while passing percent is plotted on y-axis. A diagonal straight line is created from zero to the maximum size of the aggregate (Fig. 4). This 0.45 power curve of gradations provides a concept to appraise the distribution of different sized aggregate. Based on variation in the size of aggregate, five different types of size distribution curves are familiar, namely, dense graded, gap- graded, uniformly graded, well graded and open graded (Fig. 4). The average grain size ...
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... the maximum size of the aggregate (Fig. 4). This 0.45 power curve of gradations provides a concept to appraise the distribution of different sized aggregate. Based on variation in the size of aggregate, five different types of size distribution curves are familiar, namely, dense graded, gap- graded, uniformly graded, well graded and open graded (Fig. 4). The average grain size curve of Malikhore Formation illustrate that coarse fraction has affinity with uniform gradation while finer materials show resemblance with open gradation. In spite of the fact, the gradation curve is within the upper and lower limit of coarse aggregate (Fig. 4). The size is good enough for durable and high ...
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... gap- graded, uniformly graded, well graded and open graded (Fig. 4). The average grain size curve of Malikhore Formation illustrate that coarse fraction has affinity with uniform gradation while finer materials show resemblance with open gradation. In spite of the fact, the gradation curve is within the upper and lower limit of coarse aggregate (Fig. 4). The size is good enough for durable and high strength concrete, because it requires less cement for binding. Similarly, the size is convenient to bear freeze-thaw ...
Citations
... Naseem et al. [19] 7 ...
Alkali–silica reaction (ASR) is one of the major durability issues that affect the material degradation and structural performance, compromising the service life of concrete structures. Therefore, this study was planned to investigate the potential of ASR for locally available unexplored and vastly used aggregates, as per ASTM C1260. Aggregates from five different sources (Shalozan, Abbotabad, Orakzai, Swabi and Sada) were procured from their respective crusher sites. Mineralogical components of these aggregates were studied using the petrographic analysis. Cube, prism and mortar bar specimens were cast using mixture design in accordance with ASTM C1260 and placed in sodium hydroxide solution at 80 °C for 90 days. Identical specimens were also cured in water for the purpose of comparison. It was observed that mortar bar expansion of Orakzai aggregate was higher among the other tested aggregates and greater than 0.20% at 28 days, indicating the reactive nature according to ASTM C1260. Petrographic analysis also revealed the presence of reactive silica (quartzite) in the tested Orakzai source. It was observed that the compressive and flexural strengths of specimens exposed to ASR conducive environment was lower than the identical specimens placed in water. For instance, an approximately 9% decrease in compressive strength was observed for Orakzai aggregates exposed to ASR environment at 90 days compared to similar specimens placed in water curing. Moreover, microstructural analysis showed the development of micro-cracks for specimens incorporating Orakzai source aggregates. This study assists the construction stakeholders for the potential of unexplored local aggregates with regard to ASR before its utilization in mega construction projects.
... Geologically, the park is located at the Western Fold Belt (WFB) which is outcome of collision between Indian and Eurasian plates. The WFB represents the fore land fold and thrust belt along the western margin of the Indian Plate (Bannert et al. 1993;Ahsan and Mallick 1999;Naseem et al. 2012Naseem et al. , 2016. The Balochistan province is laying in Triassic to recent strata and contains several tectonometallic and sedimentary basins which comprises of Sulaiman (middle Indus), the Balochistan basin (remains of Neotethys), and part of the suture of the Indus (central belt) and Kirthar (Indus bottom), a fragment of Gondwana (Khanoranga 2019;Akhtar et al. 2021). ...
The Hingol National Park, Pakistan, holds complex geological setting due to active geodynamic nature and association of three major tectonic plates, i.e., Eurasian, Arabian, and Indian. The geological and geomorphological characteristics of HNP were studied as a geoheritage candidate form southern Pakistan. The lithological successions exposed in HNP are highly deformed and tectonically thrusted sheets of cretaceous to Paleocene mélanges. For the first time, the geoheritage features in the HNP are highlighted and correlated with the criterion (Viii, natural) of UNESCO World Heritage list. Fourteen geological heritage and ten notable geological features are documented in this paper. These features are reported as tectonic, economical , geochemical, paleogeographical, environmental, hydrogeological, sedimentological, paleontological, and geohistorical. HNP maintains global ranking and needs professional knowledge for understating particularly the mechanism behind the geological/geomorphological features. Moreover, the HNP aesthetic properties are high due to the spectacular landscapes specifically princess of hope, sphinx of Baluchistan, beaches, oasis, and mud volcanoes which are collectively discussed as geological resources. The geoheritage diversity described in this research can be proposed as a complex geosite with distinctive geological and geomorphological characteristics due to its excellent quality of outcrops and easy access to the area. These characteristics can be helpful in documenting the scientific and geotourism perspective, making the national park as an important geosite for the better and efficient exploration of geoheritage.
... Aggregates with distinctly different origins and lithology are the most fundamentally and commonly used construction materials, constituting about 75-85% of the volume of Portland cement concrete, 93-95% of bituminous paving mixtures, and approximately 100% of the volume of unbound granular base and ballast layers (Pan and Tutumluer 2007;Ugur et al. 2010). Carbonate aggregates, which constitute the most common source of crushed rock aggregate, are abundant in the earth's crust and are also commonly suitable for these purposes (Shakoor and Brown 1996;Tepordei 2004;Naeem et al. 2014;Naseem et al. 2016). ...
Rock aggregates are the most fundamental material of highway, railroad, and other construction activities. The quality of rock aggregates for a given usage is determined by many different test methods, one of the most important of which is the Los Angeles abrasion (LAA) test as it is used to evaluate the resistance to abrasion and wear of aggregates for such applications as railroad ballast, base course material, and asphalt and concrete aggregates. In this study, the relationship between rock texture and LAA loss was investigated for 26 sources of carbonate aggregates found in Iran which constitute the most commonly quarried crushed rock. Regression analyses were used to determine whether rock texture was a useful predictor of LAA loss. The texture of rock aggregate was quantified by texture coefficient (TC), which can be used to put a value on rock texture with studies carried out on the rock thin section using image analysis. In addition, the effects of textural parameters including area weighting of grains or packing density, grain shape, grain elongation, circularity, and orientation of mineral grains, and also TC on the LAA loss were evaluated. Although the results show that weak relationships exist between textural parameters and LAA loss, a strong relationship exists between TC and LAA loss. The results indicate that many textural parameters, together with TC, can be interpreted as rock texture which influences the LAA loss. Also, the results indicate a strong negative correlation between LAA loss and TC, and can be used to predict LAA loss in practical applications.
The China-Pakistan Economic Corridor (CPEC) is an ongoing mega-construction project in Pakistan that necessitates further exploration of new natural resources of aggregate to facilitate the extensive construction. Therefore, the Late Permian strata of Chhidru and Wargal Limestone for aggregates resources were envisaged to evaluate their optimal way of construction usage through detailed geotechnical, geochemical, and petrographic analyses. Geotechnical analysis was performed under BS and ASTM standards with the help of employing different laboratory tests. A simple regression analysis was employed to ascertain mutual correlations between physical parameters. Based on the petrographic analysis, the Wargal Limestone is classified into mudstones and wackestone, and Chhidru Formation is categorized into wackestone and floatstone microfacies, both containing primary constituents of calcite and bioclasts. The geochemical analysis revealed that the Wargal Limestone and Chhidru Formation encompass calcium oxide (CaO) as the dominant mineral content. These analyses also depicted that the Wargal Limestone aggregates bear no vulnerability to alkali-aggregate reactions (AAR), whereas the Chhidru Formation tends to be susceptible to AAR and deleterious. Moreover, the coefficient of determination and strength characteristics, for instance, unconfined compressive strength and point load test were found inversely associated with bioclast concentrations and directly linked to calcite contents. Based on the geotechnical, petrographic, and geochemical analyses, the Wargal Limestone proved to be a significant potential source for both small and large-scale construction projects, such as CPEC, but the Chhidru Formation aggregates should be used with extra caution due to high silica content.
This paper investigates physico-mechanical and petrographic attributes of Paleocene Lockhart Limestone which is measured, sampled and described from Rumli (RUM) and Shah Allah Ditta (SAD) sections of Islamabad. Petrographic analysis delineates that the limestone is categorized mainly into mudstone and wackestone microfacies and dominant presence of the micrite matrix favors the strength of the rock, whereas; veins, microfractures and porosities adversely affect the stability of the rock. Based on the UCS and PLT analyses, limestone samples incorporating the lowest porosities partnered with bioclasts encompass the highest UCS and PLT values and vice versa. The physico-mechanical analyses reveal that the limestone aggregates are within limits of the respective standards (ASTM, AASHTO, BS and NHA) for utilization in wearing, coating, cement concrete. The limestone of both sections can be utilized for geotechnical purposes like crushed material and aggregate source. Simple regression analysis was employed and based on these correlations; the limestone of the studied formation is designated as moderately strong and recommended for road or bridge construction purposes.
Barite deposits of the Lasbela District, Balochistan, hosted in the Ferozabad Group (FG) of Jurassic are relatively pure and have BaO value ranging from 40.18 to 60.91 % with minor amounts of Sr, Fe and Ca. The measured average density of the studied samples (4.21 g/cm3) is compatible with the API-13A specification. The quantity of water-soluble alkaline earth metals found is very low (av. 50.76 mg/kg) and safe to be used in the drilling mud. The scanning electron microscope study of some of the selected samples revealed nearly 10 % particles are fine (<6 µm) and have equant, subrounded to rounded shape; however, larger particles (>10 µm) are tabular and low in quantity. The average content of Pb (3418 mg/kg) in the barite samples is relatively high as designated by the API specification (1000 mg/kg), while Hg, As and Cd contents are very low, except in a few samples. The average content of Sr is 1.19 %, indicating hydrothermal origin of the barite deposits of the study area and to some extent it is toxic in biological functions. Some of the samples have elevated amount of SiO2 (1.83–8.88 %) which may cause risk of silicosis in the persons either involved in milling industry or at well site. The positive loadings of first factor of principal component analysis for Ba and S, and density revealed genetic alliance with MVT/SEDEX mineralization, and negative loadings of Ca, Mg and Fe demonstrate hydrothermal alteration of host rock.
