ORIGINAL_ARTICLE
INVESTIGATION OF SHAFT AND BASE RESISTANCE OF A SINGLE BORED PILE USING OSTERBERG CELL
Evaluation of pile capacity in soil is an engineering problem of soil-structure interaction. Soil-pile interaction plays an important role in the analysis and design of pile foundations. Geotechnical engineers have recognized this role and many studies have focused on several aspects of the topics related to determination of pile resistance. There are different methods available to predict the ultimate load of a single bored pile, such as theory of bearing capacity of the soil foundation, based on pile load test, semi-empirical methods using in-situ test results, and empirical formulae were suggested by different codes of practice. Still the most reliable method to determine the bearing capacity of a pile is by static load test. This study investigates some of the important problems related to soil-pile interaction. Specific problems examined here include: identify of skin friction and end bearing resistance of pile separately, comparison between the measured results obtained from experimental methods presented by Osterberg cell, (Ocell), or conventional tests and these obtained from equations of Egyptian code for soil mechanics and foundations to evaluate and verify the applicability of different methods. The experimental results were used to study the effect of the different parameters such as pile diameter, D, pile length to pile diameter ratio (L/D), and relative density (Dr) on the pile shaft and pile base resistances of bored piles. Also, in this research, the coefficients of lateral soil pressure (KH) and bearing capacity factor (Nq) have been studied. From this study, It can be found that both pile shaft and pile base resistances have affected by the parameters D, L/D, and Dr .
https://jesaun.journals.ekb.eg/article_114319_919f5ec83ca47dbba3c93054dab43358.pdf
2007-07-01
853
867
10.21608/jesaun.2007.114319
BORED PILES
LOADS
Settlement
Skin Friction
END BEARING
SOIL-PILE INTERACTION
Mohamed
Hamed Hussein
1
Associate professor, Civil Eng. Department, Faculty of Eng., Assiut University Assiut, Egypt.
LEAD_AUTHOR
Mostafa Abdou
Abd El-Naiem
2
Lecturer, Civil Eng.Department, Faculty of Eng., Assiut University, Assiut, Egypt
AUTHOR
Ahmed
Rushdy Towfeek
3
Assistance Lecturer, Civil Eng. Department, Faculty of Eng., Al-Azhar Universit Kena, Egypt.
AUTHOR
ORIGINAL_ARTICLE
A STUDY ON FLEXURAL BEHAVIOR OF PRESTRESSED CONCRETE SIMPLE BEAMS WITH EXTERNAL TENDONS UNDER STATIC LOADS
Using a verified finite element algorithm, non-linear analysis of externally prestressed concrete beams was carried out to investigate the flexural behavior of such beams under static loads. The behavior of such beams is represented by; change of tendon’s eccentricity, load deflection diagram, the relations of load and stress in external tendons, effective depth of beam, and bond strain reduction factor. The parameters affecting the behavior of such beams include: span to depth ratio, distance between loads to span ratio, distance between deviators to span ratio, the ratio of prestressing index and reinforcement index strength and tensile and compressive reinforcement ratios. The strain variation in an external tendon was investigated on the basis of the deformation compatibility of beam. The proposed method for the numerical analysis can satisfactorily predict the behavior of externally prestressed concrete beams up to the ultimate loading stage. The stress increase in an external tendon depends mainly on the overall deformation of beam. The behavior of externally prestressed concrete beams is different than that of bonded prestressed beams due to the second order effect of tendon’s eccentricity. This point is clearly investigated in the current study. From the obtained results, a model was proposed to estimate both of the bond strain reduction factor ( R ) and effective depth reduction factor (K) considering the effect of the parameters affecting the behavior of such beams. Based on numerical analyses, a model was proposed to calculate the flexural strength of externally prestressed concrete beams considering the parameters of the study.
https://jesaun.journals.ekb.eg/article_114321_a8f351a6ae9f57b178a939982e061578.pdf
2007-07-01
869
889
10.21608/jesaun.2007.114321
Externally prestressed beam
external tendon
deviators
flexural strength
bond strain reduction factor
effective depth
Khairy
Hassan Abdelkareem
1
Civil Engineering Department, Faculty of Engineering, Assiut University, Assiut, EGYPT
LEAD_AUTHOR
ORIGINAL_ARTICLE
3-D NUMERICAL SIMULATION OF FLOW AND CLEAR WATER SCOUR BY INTERACTION BETWEEN BRIDGE PIERS
In this paper, the flow and local scour variation around single pier and by interaction between bridge piers are studied using 3D flow model. The model uses a finite-volume method to solve the non-transient NavierStokes equations for three dimensions on a general non-orthogonal grid. The k turbulence model is used to solve the Reynolds-stress term. The numerical model solves the sediment continuity equation in conjunction with van-Rijn’s bed-load sediment transport formula to simulate the bed evolution. The 3D flow model is verified through experimental study in a non cohesive bed material in an experimental flume. The different causes of local scour around the pier are simulated well, such as bow flow, down flow, horseshoe vortex, pressure variation and lee-wake vortex. It is found from this study that the local scour depth by interaction between bridge piers depends on the Froude number, the longitudinal distance between piers and the ratio of pier diameter to channel bed width. The maximum scour depth for double piers is higher than that for single pier. Furthermore, the effect of pier shape on the scour process is studied and it is found that the maximum scour depth for circular pier is less than that for rectangular one for both single and double piers. The effect of double piers on scour hole depth is diminished at L/D= 7 for circular piles and at L/D= 15 for rectangular ones. The results show good agreement between simulation and experimental results. Also, empirical equations are developed for computing the maximum scour depth due to the interaction between bridge piers at rectangular and circular shapes. Moreover, empirical equations are developed for computing the length of scour hole at single circular and rectangular piers respectively.
https://jesaun.journals.ekb.eg/article_114322_71dbfc931ac277f383475f2db15a646a.pdf
2007-07-01
891
907
10.21608/jesaun.2007.114322
Numerical Modeling
Flow
Local Scour
Double Bridge Piers
k - e Turbulence Model
Gamal
Abouzeid
1
Associate Prof., Civil Eng. Dept., Assiut University, Assiut 71516, Egypt.
LEAD_AUTHOR
Hassan
I. Mohamed
2
Lecturer, Civil Eng. Dept., Assiut University, Assiut 71516, Egypt.
AUTHOR
Shima
M. Ali
3
M. Sc. student, Eng. At Ministry of water resources and public work, Egypt.
AUTHOR
ORIGINAL_ARTICLE
FLOW CHARACTERISTICS IN COMPOUND OPEN CHANNELS WITH ONE FLOODPLAIN
This study is concerned with the flow characteristics in compound channels aiming to predict an accurate method for estimating the discharge passing through compound sections. Also it is aiming to study the flow characteristics of compound sections and trying to develop formula defining the flow behavior and its dynamics at compound sections. The study is performed experimentally in a rectangular compound section having a single floodplain. The height of main channel is changed twice to take 9cm and 15 cm. The channel bed slope is changed between 0.00243 up to 0.0037. The roughness of the channel bed is changed twice. The discharge is changed to give a range of Froude number between 0. 12 and 0.73. The ratio of floodplain depth to the main channel one (df/dm) is changed to take values between 0.22 and 0.78. Vertical photos are taken to define the lateral velocity directions. The velocity is measured by a calibrated current meter. The actual discharges are measured by means of a calibrated nozzle – meter. The results revealed that the interaction between floodplain and main channel is minimum at a horizontal plain having a level equal to 0.4 floodplain depth (0.4df). The best subdivision used for discharge estimation with minimum error is found at this level. It is found that, the capacity of compound section increases in a linear relationship with the ratio of floodplain depth to that of main channel.
https://jesaun.journals.ekb.eg/article_114340_10388d3c8537a9f64a80bf962e18a433.pdf
2007-07-01
909
931
10.21608/jesaun.2007.114340
Compound Channel
Discharge Assessment
flow characteristics
Nashat
, A., Ali
1
Professor of Hydraulic and water resources, Civil Eng. Dept., Assuit Univ., Assuit 71516, Egypt.
LEAD_AUTHOR
Ali,
A., Mohamed
2
Associate Prof., Civil Eng. Dept., Assuit Univ., Assuit 71516, Egypt
AUTHOR
Gamal
AboZeid
3
Associate Prof., Civil Eng. Dept., Assuit Univ., Assuit 71516, Egypt
AUTHOR
Wael
, E., Mohamed
4
Demonstrator, Civil Eng. Dept., Assuit Univ., Assuit 71516, Egypt
AUTHOR
ORIGINAL_ARTICLE
NUMERICAL STUDY OF UNSTEADY FLOW CHARACTERISTICS IN REGENERATIVE PUMP
Regenerative pumps are turbomachines that achieve lower mass fluxes but higher-pressure differences than comparable pumps at the same circumferential velocity. The construction of these machines is very simple and inexpensive. On the other hand their efficiency does not exceed 45 % and they are noisy. To improve efficiency and reduce noise generation, a detailed knowledge of the unsteady flow in the machine is essential. In this work, we present unsteady flow characteristics of a typical regenerative pump based on numerical results obtained by using CFX-Tascflow code. The numerical results show highly unsteady pressure fluctuations around the stripper near both inlet and outlet ports. The lower pressure predicted near the inlet port indicates that the machine is prone to suffer cavitation problems. The amplitude of pressure fluctuation near the inlet is much higher than the outlet.
https://jesaun.journals.ekb.eg/article_114351_10baabc36008efe763377b69cef9dba5.pdf
2007-07-01
933
943
10.21608/jesaun.2007.114351
Regenerative pump
Unsteady flow
Sliding interface
CFD
Tarek
A. Meakhail
1
Mechanical Power Engineering Department, High Institute of Energy, South Valley University, Aswan, Egypt
LEAD_AUTHOR
ORIGINAL_ARTICLE
APPLICATIONS OF POLE SHIFTING SELF TUNING SPEED GOVERNOR CONTROLLERS FOR MULTIMACHINE POWER SYSTEMS
Examination of the performance of fixed parameter controllers has resulted in the development of pole shifting strategies for speed governor control of multimachine power system. For a pole shifting controller design an input signal is incorporated in the self tuner. This input signal is of a composite output term of the terminal voltage and the rotor speed deviation of each generating unit. The control is based on a criterion which automatically generates a pole-shifting factor to shift the closed loop poles of the system towards the origin in the z domain without violating the control constraints. The pole-shifting factor is depicted on line at each sampling instant depending on the error measurements of the terminal voltage of each generating unit. The output of the pole shifting controller is fed in the summing point of the speed governor of each unit of the multimachine power system. Digital simulations of a 9 bus, 3 machine of a multimachine power system are performed and the comparisons of conventional governor control and self tuning control performances are presented. Nonlinear digital simulation results show the effectiveness of the proposed technique to damp out the oscillation and work effectively over a wide range of loading conditions.
https://jesaun.journals.ekb.eg/article_114342_39066ff87eccfad7573176b153c41c59.pdf
2007-07-01
945
956
10.21608/jesaun.2007.114342
Control theory
Self tuning
Control equipment and applications
G.
Shabib
gabershabib@yahoo.com
1
Electrical Engineering Department, Aswan High Institute of Energy, South Valley University, Aswan - Egypt
LEAD_AUTHOR
ORIGINAL_ARTICLE
NET EFFECTIVE GAIN OF MULTI-PUMPING RAMAN AMPLIFIER IN ULTRA-WAVELENGTH DIVISION MULTIPLEXING AND ULTRA-LONG – HAUL OPTICAL COMMUNICATION SYSTEMS
In the present paper, a net effective gain of multi-pumping Raman amplifier in ultra-wavelength division multiplexing (UW-WDM) and ultra long-haul (ULH) optical communication systems has been modeled and parametrically investigated over wide ranges of affecting parameters, taking into account the polarization effect. NR pumps are processed with or without equal spectral spacing. The effective fiber core area, the gain coefficients and the amplified spontaneous emission power ASE (as a measure of the minimum detectable power) are calculated over the operating wavelength. The above three quantities are cast in simple polynomial forms. The average net Raman gain, the on-off Raman gain, the signal-to-noise ratio at the effective length has been investigated also. The obtained results are employed to find the average repeater spacing over the spectral range under the processing. It is concluded that for repeater spacing, the total injected Raman powers are the vital factor rather than the number of amplifiers, while for the gain spectral width, the number of amplifiers is the vital factor. The central wavelength of the subset of channels that propagates in a link indicates the order of link. The total number of links in the core determines the ultimate values of different effects.
https://jesaun.journals.ekb.eg/article_114345_be431728962cb70107044e764192499d.pdf
2007-07-01
957
973
10.21608/jesaun.2007.114345
Multi-Pumping Raman Amplifiers
Ultra-Long Haul Optical Communication Systems
Ultra-Wide Wavelength Division Multiplexing
Abd El-Naser
A. Mohammed
abd_elnaser6@yahoo.com
1
Department of Electronic and Electrical Communication Engineering, Faculty of Electronics Engineering (FEE), Menouf, 32951, Minufiya University, EGYPT
LEAD_AUTHOR
ORIGINAL_ARTICLE
3D INFORMATION EXTRACTION USING REGION-BASED DEFORMABLE NET FOR MONOCULAR ROBOT NAVIGATION
This paper proposes a new method to extract the objects' 3D information for monocular robot navigation. The proposed method is based upon the Region-Based Deformable Net (RbDN) technique that we developed in [1]. This technique is modified to segment any real time video sequence captured from a single moving camera. Instead of deforming a single contour, typically used with other deformable contour methods, RbDN technique deforms a planner net. The net consists of elastic polygons that represent the segmented regions' boundaries. The deformation process tracks the location change of the polygons and their vertices across the frames. The 3D information of each object's corner is extracted based on the location change of the corresponding vertex. Furthermore, the change in the area of each region across the frames is used to accurately extract the average depth of the surface corresponding to that region. The algorithm is completely autonomous and does not require user interference, training or pre-knowledge. The experimental results demonstrate the capability of the algorithm to extract the objects' 3D information with high accuracy within a reasonable time.
https://jesaun.journals.ekb.eg/article_114347_d7200be933f94581ad66f58be43ce037.pdf
2007-07-01
975
994
10.21608/jesaun.2007.114347
Machine vision
Robot Navigation
Landmarks
Objects 3D Information Extraction
Monocular Vision
Stereo Vision
Correspondence Problem
Deformable Contours
Khaled
M. Shaaban
1
Electrical Engineering Department, Assiut University, Assiut, Egypt
LEAD_AUTHOR
Nagwa
M. Omar
2
Electrical Engineering Department, Assiut University, Assiut, Egypt
AUTHOR
ORIGINAL_ARTICLE
SOME DRILLING PARAMETERS AS A TOOL TO PREDICT DIFFERENT CATEGORIES OF ROCKS
Experimental works have been performed on five types of limestone, two types of marble and two types of granite representing sedimentary, metamorphic and igneous rocks respectively. Rate of penetration (ROP) of diamond core drill with different thrust load and rotary speeds have been obtained. Drilling Specific energy (SE) has been determined in all types of rocks under investigation at different applied loads and rotary speeds. The results were obtained for rate of penetration (ROP) to show the variation in specific energy with the different rocks. A new dimensionless index UCS/SE (Uniaxial Compressive Strength divided by specific energy) was calculated and the rates of penetration against UCS/SE for all rocks were plotted. The interpretation of these relationships clears that at lower thrust loads and higher rotary speeds the three groups of rocks were classified distinctly as three categories. Whereas, at higher thrust loads and higher rotary speeds were clearly classified as two categories, one for sedimentary only and the other for metamorphic and igneous together. From these results with other information obtained by analysis of drill cuttings and the results that have been obtained from relationships, it can be possible to identify the rock type being drilled.
https://jesaun.journals.ekb.eg/article_114353_0867e6a5c8771fda6d4e494ad8d27805.pdf
2007-07-01
995
1008
10.21608/jesaun.2007.114353
drilling specific energy
new dimensionless index (UCS/SE)
M.M.
EL-Biblawi
1
Mining and Metallurgical Engineering Department, Faculty of Engineering, Assiut University, Assiut, 71518, EGYPT
LEAD_AUTHOR
M.A.
Sayed
2
Mining and Metallurgical Engineering Department, Faculty of Engineering, Assiut University, Assiut, 71518, EGYPT
AUTHOR
M.T.
Mohamed
3
Mining and Metallurgical Engineering Department, Faculty of Engineering, Assiut University, Assiut, 71518, EGYPT
AUTHOR
W.R.
EL-Rawy
4
Mining and Metallurgical Engineering Department, Faculty of Engineering, Assiut University, Assiut, 71518, EGYPT
AUTHOR
ORIGINAL_ARTICLE
ESTIMATION OF STRESS AND STRAIN LEVELS INDUCED BY BLASTING VIBRATIONS USING MEASURED PARTICLE AND PROPAGATION VELOCITIES AT BANI KHALID QUARRY
Quarry blasting operations are necessary to supply raw materials; nevertheless they produce ground vibration stresses in the foundations of the nearby structures and may affect their stability. Subsequently, estimation of the stress-strain levels can help the engineers to evaluate safety possibilities of the high wall slopes or the nearby structures. In the present study, shallow seismic refraction surveys have been carried out in Bani Khalid quarry to determine the velocity of the compression and shear waves of the quarry area. These seismic wave velocities have been used to identify the dynamic elastic constants such as Poisson’s ratio, modulus of elasticity, and shear modulus. Ground vibration measurements, another set of field measurements, include recording of the three mutually perpendicular components of the peak particle velocities induced by the blasting operations in the quarry. The results of these measurements and calculations have been employed to estimate the normal and shear stresses and strains induced by the quarry blasting operations
https://jesaun.journals.ekb.eg/article_114358_e53c7fcdda3237ff24705a8b1e6e6ea5.pdf
2007-07-01
1009
1021
10.21608/jesaun.2007.114358
Stress and strain
Bench blasting
ground vibrations
seismic waves
and elastic constants
Elseman
I. Abdel-Rasoul
elseman1@yahoo.com
1
Associate Professor, Mining and Metallurgical Eng. Dept., Faculty of Engineering, Assiut University,
LEAD_AUTHOR
Awad
A. Omran
awaomran@yahoo.com
2
Professor, Geology Department, Faculty of Science, Assiut University,
AUTHOR
ORIGINAL_ARTICLE
THE SUSTAINABLE DEVELOPMENT IN THE ARAB WORLD ON LOCAL REGIONAL LEVELS – A COMPARATIVE ANALYSIS OF THE REALITY AND THE SCOPE OF ARAB TOWNS
Towns play a major role in the development field; because they are productive places in general as they suitably contribute in the national economical growth. Yet the process of the urban development in itself generally causes a distinct deterioration of the surrounding environmental conditions. As towns are considered places for the population growth as well as for trading and industrial activities, they intensity the consumption of energy, the deterioration of resources and the production of wasteproducts to an extent, which surpasses the endurance of the systems created by the human being and nature together, as well as it confuses the administrative abilities of administrating these systems. The acute state of this situation deteriorates with the rapid growth of the population in towns. These harmful effects or the environmental loses resulting; threaten the continuity of the production of these towns, the health of their population and their kind living. The Arab towns are facing real challenges implemented by increasing urban growth and its effects on changing the social dynamics, that change will create new possibilities for social progress, but it will also increase the greater difficulties all towns face in supplying sufficient infrastructures. The skeleton structure for any town is affected by several factors, political, social, economical, modern technology and the climatic factor, which is very difficult to study its effects by itself, as it is one of the comparatively stable factors all through the passing years and eras compared with the other changing factors, therefore to organizing the skeleton of any town we have to bear in mind modern issues, like the population density, The crowdedness problem, the air movement, transport, other necessities of health, as well the climatic factors. Several of the Arab towns administrations tried to face the new situations through development and modernization, yet the rate of increased construction growth surpassed all the expectations of these plans, which hindered the possibility of planning the suitable future directions of developing the public utilities, civil services, directing the population's activities, the investment movement, which would suit the situations the conditions and the growth constituents in these towns to realize the maximum benefit of its potentials and growth abilities. To overcome such defect most the Arab towns used to adopt plans more flexible, but they generally do not have a comprehensive look or integrating one between these towns and their surroundings, which generally consists of secondary towns or regions connected to these towns, which weakens the role of these towns in achieving the balance and looked for integrating growth on local and regional levels. For a sustainable development it must be balanced in a better way between the rural and urban areas, between little towns, middle and big ones adopting a method of development, whose axis is the human being, The ability of the towns to survive depends on their answering the people's needs through more effective investments in the fields of health, education …etc. This needs the active share of the societies in the urban development, stressing role of women as full partners in the sustainable development.
https://jesaun.journals.ekb.eg/article_114361_9d641b8613194b0c1c488b3869c72992.pdf
2007-07-01
1023
1039
10.21608/jesaun.2007.114361
Sustainable Development
environmental considerations
Saif Abdullah i
Ahmed AL-kubat
alkobati_saif@yahoo.com
1
Prof. of Urban Design Arch. Department Faculty of Engineering, Sana'a University Yemen Republic P.O.Box 14288 Sana'a
LEAD_AUTHOR
ORIGINAL_ARTICLE
URBAN HERITAGE AREAS THROUGH THE SCOPE OF GREEN ARCHITECTURE CONCEPTS (OLD CITY OF SANA'A AS AN EXAMPLE)
The urban heritage is one of the significant features of any the city's architectural personality; it represents the ancient's cleverness of dealing with their context through the generations. On the other hand, Green Architecture is on of the architectural concepts that emerged after the energy crisis in the seventies of the 20th century; when some architects developed designs, which was interested in environmental impact of the building through the building existence. The paper aims at studying urban heritage through the scope of green architecture. To achieve the paper aim we need to know more about the green architecture, which has been done in the first part of the paper. The second part is a studying of the urban heritage of Old City of Sana'a -as an example-. The last part is an evaluation of the urban heritage of Old City of Sana'a from the scope of green architecture. Finally, the research conclude that the urban heritage in old Sana'a city has most of the green architecture concepts
https://jesaun.journals.ekb.eg/article_114365_9c0b3bad685cf793492897203efbd1f1.pdf
2007-07-01
1041
1055
10.21608/jesaun.2007.114365
Wael
A. Mokbel,
1
Graduate Student Dept. of Architecture Assiut university
LEAD_AUTHOR
Ezzat
A. Morghany
2
Associated professor Dept. of Architecture Assiut university
AUTHOR
Shawkat
A. Alkady
3
Associated professor Dept. of Architecture Assiut university
AUTHOR
ORIGINAL_ARTICLE
THE SUSTAINABLE TOURISM DEVELOPMENT IN THE NORTHERN COASTAL AREA OF SAUDI ARABIA (CASE STUDY: COASTAL CITIES IN TABOUK REGION)
The objective of this research is to set up a strategic vision and a sustainable tourism development plan for the northern coastal area of the red sea in Tabouk region, northwest of Saudi Arabia, in light of National Spatial Strategy (NSS) and National Tourism Strategy considering natural and environmental resources in Tabouk region, for a balanced urban development environmentally, economically, and socially. This research will examine the potential natural, environmental and cultural resources in the coastal area of Tabouk region by applying the descriptive approach and analyzing the surveys and interviews and data collection results. The study area is located within the administration boundary of Tabouk region in northwest part of Saudi Arabia, covering over 500 km of coastal line starting from Hagel in the north of Al aqaba Gulf and ending in the south of Umlej city on the red sea. The findings in this research reveal the importance of the tourism resources in the coastal areas of Tabouk region. The study concludes that the coastal areas of Tabouk region has some of the most significant and promising areas with the ultimate potentiality for sustainable tourism development at saudi Arabia.
https://jesaun.journals.ekb.eg/article_114372_9dbd470a4a79ea90fd6f8ce9f1de8a05.pdf
2007-07-01
1057
1085
10.21608/jesaun.2007.114372
sustainable tourism development tourism development coastal development red Sea
Abd El-Aziz
Bin-Naser Al-Dosery
1
Associate Prof. of Arch. Planning, Faculty of Arch. And Planning, King Saud University, Kingdom of Saudi Arabia
LEAD_AUTHOR