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Article ; Online: Discovering blackspots caused by pavement distresses using Lagrange polynomial and safety inspections of traffic accidents

Khawaja Sheeraz / Naeem Aziz Memon / Aftab Hameed Memon / Nafees Ahmed Memon / Syed Faraz Jafri

Mehran University Research Journal of Engineering and Technology, Vol 42, Iss 4, Pp 123-

A case study for Karachi, Pakistan

2023 Volume 139

Keywords	Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Language	English
Publishing date	2023-10-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Asphalt Pavement Temperature Prediction Models

Adwan Ibrahim / Abdalrhman Milad / Zubair Ahmed Memon / Iswandaru Widyatmoko / Nuryazmin Ahmat Zanuri / Naeem Aziz Memon / Nur Izzi Md Yusoff

Applied Sciences, Vol 11, Iss 3794, p

A Review

2021 Volume 3794

Abstract: The performance of bituminous materials is mainly affected by the prevailing maximum and minimum temperatures, and their mechanical properties can vary significantly with the magnitude of the temperature changes. The given effect can be observed from ... ...

Abstract	The performance of bituminous materials is mainly affected by the prevailing maximum and minimum temperatures, and their mechanical properties can vary significantly with the magnitude of the temperature changes. The given effect can be observed from changes occurring in the bitumen or asphalt mixture stiffness and the materials’ serviceable life. Furthermore, when asphalt pavement layer are used, the temperature changes can be credited to climatic factors such as air temperature, solar radiation and wind. Thus in relevance to the discussed issue, the contents of this paper displays a comprehensive review of the collected existing 38 prediction models and broadly classifies them into their corresponding numerical, analytical and statistical models. These models further present different formulas based on the climate, environment, and methods of data collection and analyses. Corresponding to which, most models provide reasonable predictions for both minimum and maximum pavement temperatures. Some models can even predict the temperature of asphalt pavement layers on an hourly or daily basis using the provided statistical method. The analytical models can provide straight-forward solutions, but assumptions on boundary conditions should be simplified. Critical climatic and pavement factors influencing the accuracy of predicting temperature were examined. This paper recommends future studies involving coupled heat transfer model for the pavement and the environment, particularly consider to be made on the impact of surface water and temperature of pavements in urban areas.
Keywords	pavement temperature ; temperature distribution ; prediction model ; layered systems ; heat transfer ; climate ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
Language	English
Publishing date	2021-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Effect of Variation in Blending Variables on the Properties of CRMB

Naeem Aziz Memon / Kamran Ansari / Zaheer Ahmed Almani

Mehran University Research Journal of Engineering and Technology, Vol 32, Iss 2, Pp 175-

2016 Volume 182

Abstract: The enhancement in the properties of the modified blends largely depends on the proper understanding of the interaction between CR (Crumb Rubber) and bitumen, where the CR particles swell after absorbing lighter fraction from the bitumen phase. However, ... ...

Abstract	The enhancement in the properties of the modified blends largely depends on the proper understanding of the interaction between CR (Crumb Rubber) and bitumen, where the CR particles swell after absorbing lighter fraction from the bitumen phase. However, the properties of CRMB (Crumb Rubber Modified Bitumen) blends at a wide range of temperatures are considered to be somewhat unclear due to the various interaction effects of CR and base bitumen. This largely depends on the interaction conditions such as blending time, temperature, speed and device, which may alter the properties of the blend to great extent. In this study, influence of the interaction condition was investigated by looking at the viscosity with a Brookfield viscometer. For this, CR and bitumen proportions along with other material characteristics were kept constant to understand the effect of interaction parameters of the properties of the CRMB blend. A total of 12 CRMB blends were produced with unvarying combinations of material constituents. However, selected variation in the blending parameters were; blending device, duration, speed and temperature. Observations from this laboratory study indicated: (1) blending performed with the high shear mixer resulted in higher viscosity values compared to the blends produced with the low shear mixer; (2) reduced blending time was required to achieve peak and ultimate stable viscosities, when blends were produced with the high shear mixer; (3) blending temperature of 180°C has resulted in the blends with consistent properties for longer blending durations compared to the blends produced at higher temperature. As a result, results with high shear mixer were always promising, which required comparatively lower interaction temperature, time and speed.
Keywords	Crumb Rubber ; Crumb Rubber Modified Bitumen ; High Shear Mixer ; Mechanical Stirrer ; Blending Speed ; Blending Temperature ; Blending Device ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Subject code	620
Language	English
Publishing date	2016-04-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Effect of Firing on Cracking and Warping of Clay Beams

Nawab Ali Lakho / Muhammad Aucher Zardari / Naeem Aziz Memon

Mehran University Research Journal of Engineering and Technology, Vol 35, Iss 2, Pp 247-

2016 Volume 252

Abstract: Reinforced baked clay beams may be considered to be a substitute of reinforced cement concrete beams in order to build low cost houses. The baking of these clay beams can pose problems such as cracking and warping. This paper presents the effect of ... ...

Abstract	Reinforced baked clay beams may be considered to be a substitute of reinforced cement concrete beams in order to build low cost houses. The baking of these clay beams can pose problems such as cracking and warping. This paper presents the effect of different treatments applied to clay beams during baking to reduce cracking and warping. These clay beams were baked in pottery kiln in which the temperature could not be raised to the extent of fusing of clay beams placed at bottom of firing chamber. As expected, the beams were not baked properly and a number of them got cracked. Then these beams were baked in a commercial Hoffman?s kiln. The beams, in preheating stage, were moistened to full depth due to humidity and moisture of flue gases. As a result, the beams cracked and warped at the time of firing. In order to avoid the beams from being moistened by the moisture of the flue gases, different treatments were opted. Firstly, these beams were covered with plastic sheet, the cracks were reduced to some extent. Secondly, double layer of mud, with a layer of gunny bags between them, was applied. Consequently, a few cracks occurred in the beams. The treatments suggested in this paper can be used for baking of clay beams in Hoffman?s kiln at commercial level
Keywords	Baked Clay ; Firing Temperature ; Cracking ; Warping ; Flue Gases ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Subject code	690
Language	English
Publishing date	2016-04-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Reduction of Cracking and Shrinkage in Compressed Clay Beams during Drying

NAWAB ALI LAKHO / MUHAMMAD AUCHAR ZARDARI / NAEEM AZIZ MEMON

Mehran University Research Journal of Engineering and Technology, Vol 35, Iss 3, Pp 395-

2016 Volume 400

Abstract: Uncontrolled evaporation of moisture from compressed clay beams can cause surface cracks, resulting in reduction of strength. This paper presents various treatments applied to clay beams during the process of casting, compacting and drying in order to ... ...

Abstract	Uncontrolled evaporation of moisture from compressed clay beams can cause surface cracks, resulting in reduction of strength. This paper presents various treatments applied to clay beams during the process of casting, compacting and drying in order to curtail the possibility of cracking and to decrease percentage of drying shrinkage. Following treatments were applied to the beams during casting and drying: (i) a steel plate and double layer of plastic sheet was provided between the beam and the plank, (ii) the beam was enveloped with a propylene fabric sheet during casting and (iii) beams were covered with plastic sheet during drying. Using these treatments, the clay beams were cast and compacted at various intensities of compaction. The results show that the drying shrinkage was reduced to minimum and the cracks were curtailed. The rate of drying shrinkage was decreased depending upon the level of compaction. Thus at the higher degree of compaction, more density of clay beams was achieved, which resulted in higher degree of compressive strength in baked and unbaked state
Keywords	Compressed Earth Blocks ; Affordable Houses ; Compaction ; Indigenous Clay ; Drying Shrinkage and Cracks ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Subject code	660
Language	English
Publishing date	2016-07-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Estimation of Parameters and Flow Characteristics for the Design of Sanitary Sewers in Malaysia

Kamran Ansari / Zaheer Ahmed Almani / Naeem Aziz Memon

Mehran University Research Journal of Engineering and Technology, Vol 32, Iss 1, Pp 95-

2013 Volume 102

Abstract: Determination of the flow characteristics is very important for the design of sanitary sewers in any area. In the present study these are determined in the running sewers for the two parameters; per capita flow contribution and the peak flow factor. ISCO ...

Abstract	Determination of the flow characteristics is very important for the design of sanitary sewers in any area. In the present study these are determined in the running sewers for the two parameters; per capita flow contribution and the peak flow factor. ISCO area - velocity flow meter model 4250 is used for this purpose. The flow meter, before being used in the running sewers, is calibrated first in the Hydraulics and Hydrology Laboratory of the UTM (Universiti Teknologi Malaysia). During the study the flow meter is installed inside the manhole in 10 different phases in the months of June, August, September, and October 2005 to monitor the sewage flow running in it. Continuous data is recorded in the flow meter during the process and the recorded time varies between 47 hours 25 minutes and 128 hours 35 minutes. The rainfall data is also collected during the same time using an automatic rain gauge which recorded rainfall at every five minutes of interval. Both the parameters thus calculated are then compared with the Malaysian Standard for sewer design i.e. MS 1228:1991. The results show that higher values of these parameters are being used in the design of sanitary sewers and extensive study needs to be carried out to review these values for future use
Keywords	Flow Characteristics ; Peak Flow Factor ; Per Capita Flow Contribution ; Sewer Design ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Subject code	621
Language	English
Publishing date	2013-01-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Liquefaction Potential of Silty Sand in Simple Shear

Zaheer Ahmed Almani / Kamran Ansari / Naeem Aziz Memon

Mehran University Research Journal of Engineering and Technology, Vol 32, Iss 1, Pp 85-

2013 Volume 94

Abstract: In this paper, the liquefaction potential of medium dense and dense sand layers was studied by performing constant volume (undrained) cyclic simple shear tests using cyclic simple shear apparatus. Strain-controlled approach was adopted. The liquefaction ... ...

Abstract	In this paper, the liquefaction potential of medium dense and dense sand layers was studied by performing constant volume (undrained) cyclic simple shear tests using cyclic simple shear apparatus. Strain-controlled approach was adopted. The liquefaction potential of two layers of a silty sand soil profile consisting of surface medium dense layer and underlying dense sand layers were studied. A medium dense sand surface layer exhibited flow type total liquefaction in cyclic loading in few cycles after initial liquefaction. An underlying dense sand base layer showed initial liquefaction in relatively more number of cycles and then cyclic mobility due to which pore pressure increases and decreases with cycles that is the characteristics of dense sand. The pore pressure increase and decrease is directly related to decrease and increase of effective stress.
Keywords	Strain-Controlled ; Medium Dense Sand ; Dense Sand ; Liquefaction ; Cyclic Mobility ; Shear Strength ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Language	English
Publishing date	2013-01-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Development of Bed Ridges in Open Channels and their Effects on Secondary Currents and Wall Shear

Kamran Ansari / Ashfaque Ahmed Memon / Naeem Aziz Memon

Mehran University Research Journal of Engineering and Technology, Vol 31, Iss 3, Pp 503-

2012 Volume 516

Abstract: A numerical analysis of the ridges on the bed of wide, open channels and their effects on the distribution of secondary currents and wall shear is undertaken using CFD (Computational Fluid Dynamics). The presence of the lines of boil, consisting of low ... ...

Abstract	A numerical analysis of the ridges on the bed of wide, open channels and their effects on the distribution of secondary currents and wall shear is undertaken using CFD (Computational Fluid Dynamics). The presence of the lines of boil, consisting of low speed streaks, periodically in the transverse direction, is reported in the literature due to the presence of the ridges. In the present work, simulations are run on channel sections with varying the number of ridges on the bed and the size of these ridges. The effect of these variations on the flow structures and shear stress distribution in wide open channels is reported. The results offer an interesting insight into the 3D (Three-Dimensional flow structures involved and the link between flow structures and bed morpho-dynamics in prismatic channels.
Keywords	Open Channels ; CFD Modelling ; Ridges ; Boundary Shear Stress ; Secondary Currents ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Language	English
Publishing date	2012-07-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Determination of Turbulence Coefficient using Genetic Algorithms

Ashfaque Ahmed Memon / Naeem Aziz Memon / Kamran Ansari

Mehran University Research Journal of Engineering and Technology, Vol 31, Iss 4, Pp 651-

2012 Volume 658

Abstract: An effort has been made to optimally determine the status of turbulence loss coefficient in the present study. The parameter is identified in the framework of GA (Genetic Algorithm), which consequently resulted in the development of a computer model. In ... ...

Abstract	An effort has been made to optimally determine the status of turbulence loss coefficient in the present study. The parameter is identified in the framework of GA (Genetic Algorithm), which consequently resulted in the development of a computer model. In accordance with principles of the GA, the objective function, sse (sum of square of errors), is minimized between 0.009785 and 0.017565; as a result the well hydraulic parameters are optimally identified. To check validity of the model, simulated draw downs are compared against the observed ones, which indicate mean difference between them varying from 0.0049m to 0.0124m. Furthermore, validity of the model is also endorsed through statistical analysis with model efficiency varying between 99.97 and 100.00%. The model is applied to 5 data sets of step drawdown pumping test, yielding 5 values of turbulence coefficient varying between 1.01 and 2.08. Out of these 5 optimized values of turbulence coefficient none of the values is equal to 2. This scenario of variation of turbulence coefficient substantiate that turbulence coefficient is a variable and not a constant (i.e. equal to 2.0, as suggested by Jacob and Singh) while considering turbulence loss coefficient as a constant is discarded.
Keywords	Turbulence Loss Coefficient ; Well Hydraulic Parameters ; Optimization ; Genetic Algorithm. ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Subject code	532
Language	English
Publishing date	2012-10-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Influence of the Scrap Tyre Processing Techniques on the Physical Properties of the Crumb Rubber

Naeem Aziz Memon / Kamran Ansari / Zaheer Ahmed Almani

Mehran University Research Journal of Engineering and Technology, Vol 31, Iss 4, Pp 703-

2012 Volume 710

Abstract: The processing mechanism of scrap tyres to produce CR (Crumb Rubber) has a great influence on the properties of the CRMB (Crumb Rubber Modified Bitumen). A fair amount of research was observed in the literature on the bitumen modified by CR processed ... ...

Abstract	The processing mechanism of scrap tyres to produce CR (Crumb Rubber) has a great influence on the properties of the CRMB (Crumb Rubber Modified Bitumen). A fair amount of research was observed in the literature on the bitumen modified by CR processed cryogenically and ambiently. However, little or no work has been done on the CR processed by the other methods such as the Aquablast processing technique, which is a relatively a new waste tyre rubber processing technique within the CR industry. In this study, CR obtained from the two sources; ambient and Aquablast grinding techniques were primarily assessed with a helium pycnometer and SEM (Scanning Electron Microscopy) for their physical properties and appearance respectively. Observations from this laboratory study indicated: (1) the density of the ambient CR was slightly higher than the CR obtained from Aquablast technique; (2) difference in physical appearance was found insignificant.
Keywords	Crumb Rubber ; Crumb Rubber Modified Bitumen ; Ambient Crumb Rubber ; Aquablast Crumb Rubber. ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Science ; Q
Language	English
Publishing date	2012-10-01T00:00:00Z
Publisher	Mehran University of Engineering and Technology
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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