In recent years, the search for economic and environmentally friendly alternatives has become a global necessity to achieve sustainability and preserve raw materials. From this concept, natural bitumen (NB) derived from sulphur springs is now one of the most promising alternative energy resources for many applications, especially in asphalt pavement construction. Its low price and abundance characterise NB since sulphur springs produce thousands of tonnes of NB annually and are used in very limited fields. Two main objectives were adopted for this work. The first objective is to examine the virgin NB properties from five sulphur springs and compare them with petroleum asphalt. The second objective is to enhance NB properties by applying heat treatment. The experimental results reveal that heat treatment is highly effective in improving the NB properties. This was confirmed by conducting many tests, such as asphalt, Marshall, SEM-EDX, and indirect tensile strength tests. Based on the experimental test outcomes, virgin NB properties do not conform to asphalt specification limits and are unsuitable for flexible roads. Also, MS-NB significantly affected the mechanical properties of the asphalt mixture, as Marshall's stability increased by 41.3% compared to the conventional mixture. In addition, SS-NB was more effective in moisture damage resistance due to increasing the tensile strength ratio by 5.72 % and provided a higher stiffness index than the conventional mixture by 40.36%. In conclusion, the treated NB can successfully be used as a binder material in hot asphalt mixtures. ABSTRAK: Beberapa tahun kebelakangan, pencarian alternatif baharu ekonomi dan mesra alam telah menjadi satu keperluan global bagi mencapai kemampanan dan memelihara bahan mentah. Melalui konsep ini, bitumen asli (NB) yang diperoleh daripada mata air sulfur kini merupakan satu sumber tenaga alternatif yang berguna bagi digunakan dalam pelbagai aplikasi, terutamanya dalam pembinaan turapan asfalt. NB dicirikan oleh harga yang rendah dan kelimpahannya kerana mata air sulfur menghasilkan beribu-ribu tan NB setiap tahun dan digunakan dalam bidang terhad. Dua objektif utama telah dipakai untuk kajian ini. Objektif pertama adalah memeriksa sifat NB dara daripada lima mata air sulfur dan membandingkannya dengan asfalt petroleum. Objektif kedua adalah meningkatkan sifat NB dengan menggunakan rawatan haba. Dapatan eksperimen mendedahkan bahawa rawatan haba sangat berkesan dalam meningkatkan sifat NB. Ini disahkan dengan menjalankan pelbagai ujian, seperti ujian asfalt, ujian Marshall, ujian SEM-EDX, dan ujian kekuatan tegangan tidak langsung. Berdasarkan dapatan eksperimen, sifat NB dara tidak mematuhi had spesifikasi asfalt dan tidak sesuai untuk jalan fleksibel. Selain itu, MS-NB mempunyai kesan ketara pada sifat mekanikal campuran asfalt kerana kestabilan Marshalls meningkat sebanyak 41.3% berbanding campuran konvensional. Tambahan, SS-NB lebih berkesan dalam rintangan kerosakan lembapan kerana meningkatkan nisbah kekuatan tegangan sebanyak 5.72 % dan memberikan indeks kekukuhan yang lebih tinggi daripada campuran konvensional sebanyak 40.36%. Kesimpulannya, NB yang dirawat boleh berjaya digunakan sebagai bahan pengikat dalam campuran asfalt panas.
The evacuated tube solar collector ETC is studied intensively and extensively by experimental and
theoretical works, in order to investigate its performance and enhancement of heat transfer, for Baghdad climate
from April 2011 till the end of March 2012. Experimental work is carried out on a well instrumented collector
consists of 16 evacuated tubes of aspect ratio 38.6 and thermally insulated tank of volume 112L. The relation
between convective heat transfer and natural circulation inside the tube is estimated, collector efficiency, effect of
tube tilt angles, incidence angle modifier, The solar heating system is investigated under different loads pattern (i.e
closed and open flow) to evaluate the heat loss coefficient
The study aimed to analyze the effect of meteorological factors (rainfall rate and temperature) on the change in land use in the marshes of the Al‐Majar Al‐Kabir region in southern Iraq. Satellite images from Landsat 7 for 2012 and Landsat 8 for 2022 were used to monitor changes in the land coverings, the images taken from the Enhanced Thematic Mapper Plus (ETM+) and Operational Land Imager (OLI) sensors of the Landsat satellite. Geometric correction was used to convert images into a format with precise geographic coordinates using ArcMap 10.5. The maximum likelihood classification method was used to examine satellite image data using a supervised approach, and the data were analyzed statistically. We obtained clear images of the area,
... Show MoreThe aim of this research work is to study the effect of stabilizing gypseous soil, which covers vast areas in the middle, west and south parts of Iraq, using liquid asphalt on its strength properties to be used as a base course layer replacing the traditional materials of coarse aggregate and broken stones which are scarce at economical prices and hauling distances. Gypseous soil brought from Al-Ramadi City, west of Iraq, with gypsum content of 66.65%, medium curing cutback asphalt (MC-30), and hydrated lime are used in this study. The conducted tests on untreated and treated gypseous soil with different percentages of medium curing cutback asphalt (MC-30), water, and lime were: unconfined compression strength, and one dimensional confine
... Show MoreMoisture induced damage in asphaltic pavement might be considered as a serious defect that contributed to growth other distresses such as permanent deformation and fatigue cracking. This paper work aimed through an experimental effort to assess the behaviour of asphaltic mixtures that fabricated by incorporating several dosages of carbon fiber in regard to the resistance potential of harmful effect of moisture in pavement. Laboratory tests were performed on specimens containing fiber with different lengths and contents. These tests are: Marshall Test, the indirect tensile test and the index of retained strength. The optimum asphalt contents were determined based on the Marshall method. The preparation of asphaltic mixtures involved
... Show MoreGypseous soil is considered as a problematic soil for embankment construction, however, implementation of emulsified asphalt as a stabilization agent could be a proper solution for enhancing its properties as a subgrade soil. In this work, the sustainability of asphalt stabilized soil has been assessed in terms of its resistance to cyclic (freezing-thawing) and (heating-cooling) processes. Specimens have been prepared at optimum fluid content (moisture and emulsion) and tested under direct shear stresses while subjected to 30 cycles of (freezing-thawing) and (heating-cooling). Both of dry and soaked testing conditions have been implemented. Data have been observed after each 10 cycles, and compared with that of reference mix. It was conclud
... Show MoreThe problem of research is that there are ways to protect and sustain environmentally important sites in Iraq. There are no documentary sources for these sites, such as the natural landscape of natural and important natural resources, which suffer from severe environmental neglect
Objective: Dental caries is a chronic infectious disease that is prevalent worldwide in all age groups. Numerous attempts have been made to develop conservative approaches to halt caries progression and restore enamel defects. This study aimed to investigate the effect of applying grape seed extract and chicken eggshell extract on the microhardness of demineralized enamel in permanent teeth. Methods: Forty-eight sound upper first premolars were used. Following demineralization with the demineralizing solution for 96 hours, they were distributed into four groups consistent with the treatment agent used: group A was treated with casein phosphopeptide amorphous calcium phosphate (as a control group), group B was treated with grape se
... Show MoreThe unsteady state laminar mixed convection and radiation through inclined
cylindrical annulus is investigated numerically. The two heat transfer mechanisms of
convection and radiation are treated independently and simultaneously. The outer
cylinder was kept at a constant temperature while the inner cylinder was heated with
constant heat flux. The study involved numerical solution of the governing equations
which are continuity, momentum and energy equations using finite difference method
(FDM), where the body fitted coordinate system (BFC) was used to generate the grid
mesh for computational plane. A computer program (Fortran 90) was built to calculate
the bulk Nusselt number (Nub) after reaching steady state con
Many waste materials can be repurposed effectively within asphalt concrete to enhance the performance and sustainability of pavement. One of these waste materials is sawdust ash (SDA). This study explores the beneficial use of SDA as a substitute for limestone dust (LD) mineral filler in asphalt concrete. The replacement rate was 0%, 15%, 30%, 45%, and 60% by weight of total mineral filler. Scanning electron microscopy (SEM) was employed to assess the surface morphology of Sawdust (SD), SDA, and LD. In addition, a series of tests, including Marshall stability and flow, indirect tensile strength,moisture susceptibility, and repeated uniaxial loading tests, were conducted to examine the performance characteristics of asphalt mixtures of diffe
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