Stability and Volumetric Properties of Colored Asphalt Mixtures Containing Iron Oxide

The objective of this paper is find the effect of using iron oxide as a filler on the Marshall stability, flow and the volumetric properties of HMA and compared the results with conventional HMA using limestone dust. Three blends were used: coarse, mid and fine with neat bitumen (AC 40-50). One aggregate type (crushed) with two types of fillers: limestone and iron oxide III (α- ) with three different filler content 6%, 8% and 10%. The Marshall mix design was conducted on the three blends and the optimum binder content is computed for each blend. The Marshall stability test results and the volumetric properties analysis showed that increasing the iron oxide content from 6% to 10% increases the stability about 28%, 17% , 16% for the coarse , mid and fine mixtures respectively. This increment in stability of mixtures using iron oxide related to the increment in specific gravity of the mix (Gmb) by (1.3% to 1.5% about 30 to 50 kg/m3). On the other hand, the flow of mixtures is decreased about (5%) for mixes using iron oxide than the ones that used limestone as filler. The fine blend with 10% iron oxide exhibit the highest stability of 13.3 kN. While the coarse blend stability was 10 kN for the same filler type and content. Generally, the Marshall Test results of HMA using iron oxide as filler showed better resistance to plastic deformation, also produce denser HMA with higher stiffness. On the other hand, the volumetric properties analysis showed lesser values as compared with conventional mixture where the void in mineral aggregates and void filled with asphalt has decreased but within the acceptable limits.

The Corelation of Compliance to Use PPE (Mask) and The Event of Respiratory Disorders in Workers in Bukit Kapur Jaddih, Parseh Village, Socah District, Bangkalan Regency

The process of limestone mining will resulted in limestone dust on the working environment. This can lead to inhalation of the limestone dust which can cause respiratory problems.The type of the research was analytic with Cross Sectional design. The population was all workers in Bukit Kapur Jaddih, Parseh Village, Socah District; 52 workers. The sample was 45 workers taken by simple random sampling technique. The independent variable was compliance to use mask protective equipment, while the dependent variable was respiratory disorders. The data was collected by questionnaires and observation physical observation. The data was analyzed using Lambda test, with α= 0.05.The results of the research showed that workers who did not use PPE (masks) were 35 workers (77.8%), who experienced respiratory problems were 39 workers (86.7%), and 6 workers (13.3%) did not experience respiratory problems. The lambda test results p Value of 0.073>α (0.05) meant that H0 was accepted and H1 was rejected. The compliance to use personal protective equipment (masks) and the presence of respiratory problems showed no correlation. For this reason, workers must continue to use masks while working to protect themselves from the effects of occupational breathing (lime dust).

Influence and Possibility of Using Limestone Dust Replacement of Sand for Sustainability in Concrete Production

This paper aimed to assess the potential of using limestone dust to replace sand at levels of 0, 20, 40, 60, 80 and 100% by weight. Concrete mix design for cement : fine aggregate : coarse aggregate was 1: 2 : 4 and 0.40, 0.50, 0.60 water-to-cement ratios were used. The study started by testing the basic properties of the material. The compressive strength test was done with curing for 7, 14, 21 and 28 days and modulus of elasticity of concrete at 28 days, after which the microstructural properties of concrete modified with limestone dust were investigated. The study found that the concrete had better workability when increasing the limestone dust content. The incorporation of 40% limestone dust at 0.50 water-to-cement ratios was found to improve the compressive strength of the concrete and resulted in the maximum compressive strength. However, high levels of replacement lead to porous microstructures. Moreover, the use of limestone dust in concrete production tends to be more cost-effective. Therefore, the results of this research seemingly provide confirmation and support for the utilization of these waste materials by reducing the use of natural resources. Further, it is a goal of local governments to help promote the value of limestone dust for future use.

Application of Waste Rock Dust in Cement Binding Mixtures Used in Roadway

The article contains the results of research on the effect of waste rock dust on the properties of cement-bound mixtures. Gabbro-limestone dust with a significant proportion of active silica and calcium carbonate was used for the tests. The results of strength tests after 28 days of maturation with a variable proportion of cement (3%, 5%, 7%) and rock dust (0%, 10%, 20%) are presented. The stabilized aggregate was fine sand. The obtained results did not show the expected strength and frost resistance of the tested samples. The analysis of the results shows that the addition of rock dust is not applicable in dusty soils.

Production of Light Weight Foam Concrete with Sustainable Materials

Most of the recent works related to the construction industry in Iraq are focused on investigating the validity of local raw materials as alternatives to the imported materials necessary for some practical applications, especially in thermal and sound insulation. This investigation includes the use of limestone dust as partial substitution of cement in combination with foam agent and silica fume to produce sustainable Lightweight Foam Concrete (LWFC). This study consists of two stages. In the first stage, trial mixes were performed to find the optimum dosage of foam agent. Limestone dust was used as a partial replacement for cement. Chemical analysis and fineness showed great similarity with cement. Many concrete mixes were prepared with the content of lime dust powder being 10%, 14%, and 18% as partial replacement of cement by weight. The results indicate that the compressive strength at 7, 28, and 90 days of age was increased for specimens with 14% limestone dust. The best results in compressive strength show an increase at 7 days and a decrease at 28 and 90 days for concrete specimens with 14% limestone dust. In addition, the results show a decrease in dry density for concrete containing 14% lime dust. In the second stage, different percentages of Polypropylene Fibers were added to the concrete, all mixes, containing a constant content of limestone dust of 14% by weight of cement, were modified using different percentages of Polypropylene Fibers (1%, 1.5 %, and 2% by volume) and the best percentage was found to be 1%. The addition of Polypropylene Fibers enhances splitting tensile and flexural strength at 28 days by 14.55% and 55% respectively.

The Effect of Nanomaterials on the Properties of Limestone Dust Green Concrete

Portland cement is considered the most involved product in environmental pollution. It is responsible for about 10% of global CO2 emissions [1]. Limestone dust is a by-product of limestone plants and it is produced in thousands of tons annually as waste material. To fulfill sustainability requirements, concrete production is recommended to reduce Portland cement usage with the use of alternative or waste materials. The production of sustainable high strength concrete by using nanomaterials is one of the aims of this study. Limestone dust in 12, 16, and 20% by weight of cement replaced cement in this study. The study was divided into two parts: the first was devoted to the investigation of the best percentage of replacement of waste lime. The second part of the study evaluated the performance of concrete when adding nanomaterials. Three percentages of cement replacement 0.5%, 1%, and 1.5% with nano-Al2O3 were used. The most efficient content of hydrated lime used in this study which achieves sustainability and maintains the quality of concrete was (16%). On the other hand, it was found that the best percentage of nano-Al2O3 as a partial replacement of cement is 1.5%.

Influence of Marble Dust Filler on Marshal Properties of Hot Mix Asphalt

Literature review reveals that mineral fillers play a vital role in altering the properties of asphalt concrete. Despite filler being a small part of asphalt, has a predominant effect on the performance characteristics of asphalt concrete. Millions tons of marble waste is being generated by marble processing industries, leading to environmental pollution and loss of valuable land. Developed countries have strict policies for waste disposal whereas in developing countries there are almost no policies. Hence, in this research, an effort has been made to evaluate the influence of marble dust on the strength properties and permanent deformation resistance of asphalt concrete. For this purpose optimum binder content has been determined by using 5.5% conventional limestone dust filler and after determination of optimum binder content, stone dust has been replaced with marble dust in increments of twenty five percent (i.e 0%, 25%, 50%, 75%, 100% ). The results of the tests performed on marble dust modified asphalt revealed that marble dust modified asphalt containing 50% marble dust have shown improvement in Marshal Stability and Flow values. Incorporation of marble dust up to 25% and 50% has resulted in better volumetric properties in comparison with stone dust made mixes. Keeping in view the improvement in properties of asphalt concrete in connection with marble dust, the utilization of freely available marble dust in asphalt concrete will have a marked impact in reducing the cost of asphalt concrete as well as minimizing the environmental problems due to disposal of waste marble dust. Keywords: Asphalt Concrete, Marble Dust, Limestone dust, Marshal Stability and Flow

Performance characteristics of different mineral filler in asphalt concrete mixtures

With the increase of traffic load in Canada, asphalt mixtures are required to sustain heavier loads and withstand the harsh Canadian winter. This requires careful design and material selection. This study evaluates the performance of different types of mineral filler in asphalt pavements. Five 19mm Superpave mixes were tested with four types of mineral filler namely fly ash (Class C and Class F). Blast Furnace Slag and General Use Portland cement along with a control mix with limestone dust. The results showed that, Class C fly ash generated the most economical mix by reducing 0.3% asphalt content of total mix. The indirect tensile strength (ITS) and tensile strength ration (TSR) test results were used to evaluate the effects of different fillers for water susceptibility. Both types of fly ashes have excellent results on Tensile Strength Ratio (TSR) which increase resistance to water susceptibility. These mixes have a very positive effect on stripping resistance. Improvements in binder properties were shown after short and long term aging which was attributable to the reduction of oxidation and aging effect. Binder with fly ash has the best rutting and fatigue resistance out of all tested binder samples.