UET Peshawar Publications Site (University of Engineering and Technology, Peshawar)
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MOISTURE DAMAGE IN ASPHALT MIXTURES FROM SATS TEST AND X-RAY CT
No full textThis study investigated damage in asphalt due to moisture by using the modified SATS (saturation aging tensile stiffness) test along with image analysis. Specimens made from granite aggregate and limestone aggregate and of high grade (hard) bitumen were tested in the modified SATS test. The samples were scanned within an X-ray CT before the testing using SATS, after the initial saturation and at the completion of SATS test. Bitumen was extracted from tested specimens and scanned separately in a high resolution Nanotom. The extracted bitumen was tested in a DSR for Shear properties. The specimens made from granite (acidic) and limestone (basic) aggregate were found to have similar permeability and was high for specimens having high design void content. Specimens made from basic aggregate had higher stiffness value than the specimens made from acidic aggregate. The Master curve of aged binder is different to that of virgin binder (bitumen). The microstructure of binder observed was different for aged and virgin binder
Dynamic Modeling and Starting Behavior of a Small Horizontal Axis Wind Turbine
No full text
Small, stand-alone wind turbines are a possible solution to the energy requirements of remote areas in Pakistan. However except for the coastal areas, wind speeds available in various areas of Pakistan are low to medium, especially in the northern areas. It is possible to produce significant power from a small wind turbine at low wind speeds provided the turbine can be started. In this paper “BEM function” and “Aerodynamic function” are used based on the Blade element momentum theory. These Matlab functions calculate the wind turbine blade parameters and aerodynamic forces that will act on wind turbine blades. Pro/E models were then developed on the basis of these parameters. Pro/E models were imported into ADAMS to calculate the output torques. Our analysis shows that most of the starting torque comes from the hub section of the blade. Various changes were incorporated into ADAMS models near the hub region of the wind turbine blade which showed an increase in the staring torque due to an increase in the blade angles and chord lengths. The wind turbine designs for the selected locations of Pakistan were successfully optimized by improving their starting behavior. 
DETWINNING OF THE MARTENSITE PHASE IN SHAPE MEMORY ALLOYS (SMAs) AND THE INFLUENCE OF PRESTRESS IN SMA ACTUATORS
No full textThe unique characteristic, Shape Memory Effect (SME), of Shape Memory Alloys (SMAs), is primarily investigated by researchers as an economical source of actuation supplemented by its simple operating principle, and elimination of moving parts. Depending upon whether the SMA wire is martensitic, in transition, or austenitic phase, it exhibits different elastic isothermal behaviour. The microstructure is altered by the stress and thermal levels at both the low temperature phase and the high temperature phase. Precise experimental results for the isothermal measurements in the detwinning of the martensite phase of Nitinol and the influence of prestress in the performance of SMA wire actuators is presented in this study. Force of actuation and the displacement due to contraction during quazi-static actuation (transformation) and its dominance are illustrated for Nitinol wires used in SMA actuators
SEISMIC PERFORMANCE EVALUATION OF BRICK MASONRY SHEAR WALLS CONSTRUCTED IN STONE DUST MORTAR
No full textAn experimental study to evaluate the seismic performance of unreinforced brick masonry (URBM) shear walls constructed in cement, sand and stone dust mortar being widely used in Northern Pakistan is presented. In-plane shear-compression tests were carried out on twelve walls, using quasi-static cyclic loading. Testing set produced double bending curvature in walls. The effect of aspect ratio and pre-compression levels on various parameters used to quantify seismic performance is examined. Experimental work showed that walls with medium to high aspect ratios failed in diagonal tensile shear failure mode while squat walls failed in diagonal shear followed by bed-joint sliding. The diagonal tensile shear strengths of the walls determined from experimental work were then compared with Turnsek and Sheppard equation used to determine diagonal tensile shear strength of URBM walls. Influence of the pre-compression level on the lateral displacement ductility, drift ratio and equivalent viscous damping of the walls is discussed. Finally, drift ratios for performance levels corresponding to various damage levels, for unreinforced brick masonry walls, are proposed on the basis of experimental results
PERFORMANCE OF BRICK MASONRY CAVITY WALLS WITH DIFFERENT WALL TIES
No full textThis paper presents a study about the behavior of brick masonry cavity walls. Three types of cavity walls were tested, each having two wythes of 4½ inches thickness and 2 inches cavity between the two wythes. The first type did not have any ties, the second types had I-shaped ties while the last one had Z-shaped ties. A total of six specimens were fabricated and tested, two specimens for each of the three wall types. The specimens were then subjected to constant vertical and horizontal cyclic loads in a displacement controlled environment. Lateral strength, stiffness and ductility of the walls were determined and compared.
Test results show that use of ties increases stiffness of cavity walls, the increase being higher in the case of I-shaped ties compared to Z-shaped ties. The ductility also increased with I-type wall ties. However, wall ties have no effect on the lateral strength
INVESTIGATION TO CHECK THE FEASIBILITY OF COMPOSTING FOR SMALL CITIES IN DEVELOPING WORLD: A CASE STUDY OF TAXILA CITY
No full textThe case study presented herein investigates the composition of solid communal waste from a small city in a developing world and investigates the feasibility of using composting waste treatment. Taxila, a small city in Rawalpindi District, is selected as a focal area for this study and to start with the prevalent major environmental problems resulting from poor solid waste management were investigated. In the next stage of investigation, focal area was further subdivided into three neighbourhoods while considering the population and living standards of dwellers, with these zones named as poor, average, and rich. A total of fifty, thirty and fifteen sampling sites are selected from each of these zones respectively. Solid waste samples are collected from the selected sites for a week on daily basis, which are then analyzed to find their composition and are recorded accordingly for each zone. The analyses of collected samples indicated that almost 60-70% of generated communal waste from all three zones is organic in nature and that the composting option for such communal waste could be a more sustainable and economical solution when compared to sanitary land filling. The research findings indicated that biodegradable communal solid waste composition in small cities of developing world is suitable for composting that could help to minimize the harmful environmental impacts on life from open dumping and sanitary land filling of municipal wastes. 
PARAMETRIC ANALYSIS OF VARIOUS CONTROL ALGORITHMS FOR SEMI-ACTIVE SUSPENSION SYSTEM
No full textThe research paper involves modeling of passive and semi-active suspension systems using quarter car model. Different systems incorporating control strategies of groundhook, skyhook and hybrid are modeled on the basis of fuzzy logic control. A novel optimized control system is also developed that utilizes relative displacement and relative velocity across the masses as inputs to the fuzzy logic controller resulting in the output of modulating damping coefficient. A comparison of all the designed systems is carried out with the passive system for ascertaining ride comfort and road handling characteristics. The optimized system outperforms all other systems in both the parameters based on the rapid stabilizing time and minimum percentage overshoot. The optimized system comprises three membership functions for each of the inputs resulting in only nine rules thus enabling faster processing of the controller besides improved performance. The results manifest successful designing of an optimized fuzzy logic based control strategy for semi-active suspensions
LABORATORY MIX DESIGN OF ASPHALT CONTAINING RE-CLAIMED MATERIAL
No full textThis paper presents a study on the production of asphalt test specimens in the laboratory containing reclaimed asphalt. The mixtures considered were stone mastic asphalt concrete mixtures containing up to 30% of reclaimed asphalt. Specimens were compacted to the reference density obtained from the Marshall mix design. Gyration compaction method was used for preparing specimens for the experimental programme, while coring and cutting methods and X-ray computed tomography were used to investigate the change in properties within the specimens and to validate the selected methodology. The study concluded that gyratory compaction is suitable to produce homogeneous test specimens also for mixtures containing high amount of reclaimed asphalt. Nevertheless, preliminary trials for each material are mandatory, as well as final coring and trimming of the specimens due to side effects
PERFORMANCE ANALYSIS OF FORWARD ERROR CORRECTION AIDED P2P LIVE-VIDEO STREAMING
No full textPeer-2-Peer (P2P) technologies are rapidly advancing and have already proven successful in the form of various bandwidth demanding applications such as file-transfer and video streaming. The major advantage of the P2P technologies is its built-in scalability feature, relative to traditional client- server architecture. Therefore, keeping in view the large number of users involved in live video-streaming, P2P technology can be considered as a valuable tool aiming to broadcast live-video contents to a large number of users over the internet. Although, there is lot of research going on in analyzing the performance of P2P video streaming in heterogeneous networking scenarios, but to the best of our knowledge no work is done in analyzing the impact of Forward Error Correction (FEC) on the performance of P2P live-video streaming. In this paper we analyze the performance and characteristics of P2P live-video streaming on end-user quality of experience while employing FEC on the coded video packets. Additionally, in-order to carry out the performance analysis with reference to non-error protected benchmarker system; we utilized a realistic realtime French distributed Grid facility known as Grid'5000. More specifically, the performance of the system is evaluated while considering various realistic P2P video streaming constraints, such as limited playout delay, limited upload bandwidth and video rates. We concluded that the FEC will result in noticeable performance improvement in a scenario where each peer is connected with limited number of other peers that have the required contents for download. In such a situation the portion of the stream corrupted due to channel errors may not be recovered with the help of other accessible peers. However, if each peer has more connected peers with various alternative options to download the corrupted contents, then the employment of FEC may not have very noticeable advantage on the performance of the P2P video streaming system
WATER QUALITY INDEX OF SHALLOW AND DEEP GROUNDWATER DURING WET AND DRY SEASON OF PESHAWARBASIN
No full textThe main objective of this study was to estimate the suitability of shallow and deep groundwater wells for human and animal consumption from water quality index for irrigation and drinking purpose. A total of 95 groundwater samples at 1.5 to 30 m depths were collected in triplicate during wet and dry seasons. All samples were analyzed for pH, EC, TDS, SO42-, HCO3, CO3, Cl, Ca2+, Mg2+, Na+ , Fe+3 and K+. The result of this study showed that according to water quality index (WQI) of WHO all groundwater samples were categorized as good water and considered suitable for drinking apart from a few exceptions. The Sodium Adsorption Ratio of all groundwater was less than 10. Some of the groundwater showed more than 2.5 meq L-1 of Residual Sodium Carbonate. This suggests that groundwater is suitable for irrigation purpose in all seasons