Aging and Rheological Properties of Latex and Crumb Rubber Modified Bitumen Using Dynamic Shear Rheometer

Rubberized bitumen technology has been applied for a long time to enhance the performance of the asphalt pavement. In this research, the influence of natural rubber (NR) latex and crumb rubber (CR) on the conventional and rheological characteristics of 80/100 penetration grade bitumen before and after aging was compared. Conventional tests of penetration, ring and ball temperature, and ductility were conducted to evaluate the consistency of base bitumen and rubberized bitumen. A dynamic shear rheometer (DSR) test was carried out to evaluate the viscoelastic characteristics of the base and rubberized bitumen. The results showed that the addition of NR latex and CR reduced the penetration grade and increased the ring and ball temperature and ductility of the rubberized bitumen. This indicates that promising enhancement of the bitumen properties can be expected with the addition of NR latex and CR. The rheological properties analysis results showed that addition of CR up to 8% and NR latex up to 4% improved the complex modulus and rutting resistance of the rubberized bitumen compared to conventional bitumen. This indicates that the application of NR latex and CR in bitumen modification is expected to improve the durability of asphalt pavement.

Application of Non-Model Dependent Hybrid Higher-Order Differential Feedback Controller on Crane System

Gantry Crane is a machine used for shipping of goods from one point to another. Speed, accuracy and safety are of paramount importance in gantry crane (GC) operation, but operating GC results in unwanted sway which degrades the accuracy and safety. In this paper, hybrid control schemes are proposed for precise trolley position control and sway suppression in GC systems. Output Based input shaping (OBIS) filter was designed using the output of the system for sway suppression and proportional integral derivative (PID), linear quadratic regulator (LQR), higher order differential feedback (HODF) controllers were incorporated separately for precise trolley position control. Based on Simulation studies and analysis, it was observed that LQR-OBIS controller shown more precise tracking and higher sway reduction control. But HODFC-OBIS is a model-free control schemes hence more robust

Prediction of Linear Viscoelastic Rheological Properties for Composite Nanosilica/Polyethylene Modified Bitumen Using Response Surface Methodology

This study evaluates the suitability of response surface methodology (RSM) to describe the linear viscoelastic (LVE) rheological properties of composite nanosilica/polyethylene modified binder. Two independent and three response variables were investigated, the independent variables were temperature and nanosilica content whilethe response variables are phase angle and complex modulus. Each of the independent variables was varied over three levels. The temperature was varied in the range of 35 to 55 OC and nanosilica was varied from 2 to 6%. RSM was used for the evaluation based on Central Composite Design (CCD) design. From the results, a high correlation coefficient (R2) of 0.9999 and 0.9953 were obtained for complex modulus and phase angle. This confirms that the experimental values obtained are in real agreement with the developed quadratic models. Analysis of the individual effects of temperature and nanosilica content reveals that all the responses are influenced by the interaction of both the two independent variables but highly influenced by temperature than nanosilica content

Vibrations and Intelligent Tracking Control of Single Link Flexible Manipulator

Residual vibrations and oscillations at the Endpoint due to flexible body motions are big challenges in control of single link flexible manipulators. This makes payloads positioning very difficult and hence less efficient and low productivity. In this paper, a hybrid intelligent control of single link flexible manipulator is proposed. Output-based filter (OBF) was designed using the signal output of the system to suppress the tip deflections and it was incorporated with both linear quadratic regulator (LQR) controller and fuzzy logic controller for set point tracking control of the system. Based on the Simulation results, it was observed that, a good tracking and significant tip deflections reduction was achieved. This was measured using the time response analysis. OBF-LQR performed better and more compatible then OBF-fuzzy

Experimental and numerical investigation of thermosyphon heat pipe performance at various inclination angles

Interest in the use of heat pipes in solar applications is increasing due to their role in improving the heat transfer performance of solar collectors. In order to effectively utilise heat pipes, their performance under various operating conditions and inclination angles need to be investigated. In this work, numerical and experimental studies were carried out to investigate the effects of heat input and inclination angle on the wall temperature distributions and thermal resistance of thermosyphon heat pipe. A Computational Fluid Dynamics (CFD) model was developed using ANSYS Fluent to simulate the flow and mass transfer using volume of fluid (VOF) approach together with user - defined function (UDF) to simulate the phase change processes at various inclination angles. Experiments were carried out to validate the CFD model at heat inputs of 81.69W and 101.55W with temperature distribution results showing good agreement of ±4.2% average deviation. Also the predicted thermal resistance at different inclination angles showed good agreement with the experimental ones with maximum deviation of ±5.7%. Results showed that as the heat input increases, the heat pipe wall temperature increases and the thermal resistance decreases. Experimental and numerical results showed that increasing the inclination angle will improve the thermosyphon heat pipe performance to reach its maximum value at 90o, but this effect decreases as the heat input increases

Circular economy potential and contributions of petroleum industry sludge utilization to environmental sustainability through engineered processes - a review

The petroleum industry activities unavoidably generate a large quantity of sludge named Petroleum industry sludge (PIS). The generation rate has been increasing because of the ascending energy demand. It is a potential energy resource. PIS has been shown to contain hazardous constituents that may have negative consequences on the environment and public health. Thus, the treatment and disposal of this waste is a global issue. Numerous treatment methods have been demonstrated to reduce sludge volume and toxicity and recover petroleum components. The sludge qualities affect how effective they are. These treatment strategies can reduce the toxic substances in sludge and reduce their detrimental effects on human health and the environment. However, because of the sludge's tenacious character, only a few technologies can meet strict environmental laws while using a sizable amount of water, electricity, and chemicals. PIS treatment methods that are both waste-free and cost-effective are currently unavailable. In terms of environmental engineering significance, this study adopted the systematic review to discuss the waste to resource potential applications of PIS for reusability in sustainable construction, wastewater treatment applications, and gas generation. PIS application ineffective microorganism biofertilizer production, levan production, rubber tires manufacturing, metal catalysts synthesis, carbon–clay composites for use in sensors and electronic devices were also discussed. That is not enough, this review also found that the adoption of the circular economy that represents a new direction to create value and prosperity by elongating product lifespan and moving the waste from the end of the supply chain to the outset is very important. Thus, the circular economy potential of PIS to achieve self-cycle operation through the concept of “wastes-treat-wastes” in the petroleum industry was extensively discussed

EFFECT OF NANOSILICA ADDITIVE ON THE PERFORMANCE OF POLYMER MODIFIED ASPHALT BINDERS AND MIXTURES

Bitumen is essentially the main material for construction of flexible pavement. However, large increase in axle load and traffic volume together with harsh environmental conditions causes severe distresses such as rutting deformation and fatigue cracking on flexible pavements

EFFECT OF NANOSILICA ADDITIVE ON THE PERFORMANCE OF POLYMER MODIFIED ASPHALT BINDERS AND MIXTURES

Bitumen is essentially the main material for construction of flexible pavement. However, large increase in axle load and traffic volume together with harsh environmental conditions causes severe distresses such as rutting deformation and fatigue cracking on flexible pavements

Effect of nanosilica particles on polypropylene polymer modified asphalt mixture performance

The current study was conducted to investigate the effect of nanosilica particles on the performance characteristics of polymer modified asphalt binders. In this study, control 80/100 binder were modified with polypropylene polymer and nanosilica particles at concentration of 0%–4%. Both nanosilica particles and polypropylene polymer were added by weight of total bitumen content. The asphalt performance tests flexural four point beam fatigue test, indirect tensile strength, indirect tensile stiffness modulus and draindown tests are conducted to evaluate the effect of nanosilica particles. The results of the study shows that nanosilica particles improves the fatigue properties of polypropylene polymer modified binder. This indicates that nanosilica particles have significant effect on improving the performance properties of polymer modified binders. Also, the result reveals that thermoplastic polymer polypropylene with nanosilica particles when used as bitumen modifiers improve the performance and durability of asphalt mixtures. Keywords: Polypropylene, Fatigue cracking, Stiffness modulus, Modified asphalt, Draindow

Rheological Evaluation of Asphalt Cement Derived from Alberta Oil-sand Bitumen at Different Distillation Temperatures

In this study, high, intermediate and low temperature properties of two crude oil asphalts and three asphalts derived from Alberta oil sands bitumen distilled at temperatures of 400 C, 430 C and 460 C were evaluated. High and intermediate temperature properties of the asphalt binders at different distillation temperatures were studied using a dynamic shear rheometer (DSR) through the performance grading (PG) tests. Low-temperature properties and performance grading were evaluated using a bending beam rheometer (BBR). The DSR high-temperature analysis indicated that oil sand bitumens distilled at high temperatures have significantly higher stiffness and more resistant to permanent deformation. BBR test results showed that irrespective of the asphalt source, oil sand bitumens distilled at lower temperatures are more resistant to cracking at low temperatures. The overall results indicate that oil sand bitumens are thus suitable to be used for both asphalt pavements requiring low and high-temperature resistance.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author