Flexural strengthening of RC one way solid slab with Strain Hardening Cementitious Composites (SHCC)

Basha, Ali,Fayed, Sabry,Mansour, Walid Techno-Press 2020 Advances in concrete construction Vol.9 No.5

The main aim of the current research is to investigate the flexural behavior of the reinforced concrete (RC) slabs strengthened with strain hardening cementitious composites (SHCC) experimentally and numerically. Seven RC slabs were prepared and tested under four-points loading test. One un-strengthened slab considered as control specimen while six RC slabs were strengthened with reinforced SHCC layers. The SHCC layers had different reinforcement ratios and different thicknesses. The results showed that the proposed strengthening techniques significantly increased the ultimate failure load and the ductility index up to 25% and 22%, respectively, compared to the control RC slab. Moreover, a three dimensional (3D) finite element model was proposed to analyze the strengthened RC slabs. It was found that the results of the proposed numerical model well agreed with the experimental responses. The validated numerical model used to study many parameters of the SHCC layer such as the reinforcement ratios and the different thicknesses. In addition, steel connectors were suggested to adjoin the concrete/SHCC interface to enhance the flexural performance of the strengthened RC slabs. It was noticed that using the SHCC layer with thickness over 40 mm changed the failure mode from the concrete cover separation to the SHCC layer debonding. Also, the steel connectors prevented the debonding failure pattern and enhanced both the ultimate failure load and the ductility index. Furthermore, a theoretical equation was proposed to predict the ultimate load of the tested RC slabs. The theoretical and experimental ultimate loads are seen to be in fairly good agreement.

Fuzzy Based Multi-Hop Broadcasting in High-Mobility VANETs

Basha, S. Karimulla,Shankar, T.N. International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.3

Vehicular Ad hoc Network (VANET) is an extension paradigm of moving vehicles to communicate with wireless transmission devices within a certain geographical limit without any fixed infrastructure. The vehicles have most important participation in this model is usually positioned quite dimly within the certain radio range. Fuzzy based multi-hop broadcast protocol is better than conventional message dissemination techniques in high-mobility VANETs, is proposed in this research work. Generally, in a transmission range the existing number of nodes is obstacle for rebroadcasting that can be improved by reducing number of intermediate forwarding points. The proposed protocol stresses on transmission of emergency message projection by utilization subset of surrounding nodes with consideration of three metrics: inter-vehicle distance, node density and signal strength. The proposed protocol is fuzzy MHB. The method assessment is accomplished in OMNeT++, SUMO and MATLAB environment to prove the efficiency of it.

Rigorous formulation for electromagnetic plane-wave scattering from a general-shaped groove in a perfectly conducting plane: reply to comment

Basha, M.A.,Chaudhuri, S.K.,Safavi-Naeini, S.,Eom, H.J. OPTICAL SOC- AMERICA 2008 Journal of the Optical Society of America. A, Opti Vol.25 No.5

Linear polyesters as effective corrosion inhibitors for steel rebars in chloride induced alkaline medium – An electrochemical approach

Basha Nusrath Unnisa, Chan,Nirmala Devi, Gowraraju,Hemapriya, Venkatesan,Chitra, Subramanian,Chung, Ill-Min,Kim, Seung-Hyun,Prabakaran, Mayakrishnan Elsevier 2018 Construction & building materials Vol.165 No.-

<P><B>Abstract</B></P> <P>As a motto of framing the strategies to minimise the deterioration in steel reinforced concrete structures as well as the fact that the work carried out with polymers are rare and scanty, polyesters namely Poly (Glycerol azealate) (PGAZ) and 4-(1-(4-methoxy phenyl) cyclo hexyl)phenyl 9-oxodecanoate (MPOD) were synthesised and evaluated for rebar corrosion in simulated concrete pore solution (SCP) for the first time at selected concentrations of 10, 100, 1000 ppm levels with an aid of electrochemical impedance and potentiodynamic polarisation techniques. Nyquist plots favoured increased R<SUB>ct</SUB> values suggesting the formation of barrier. Tafel plots represented cathodic inhibition. The experimental datas were best fitted with Langmuir adsorption isotherm facilitating monolayer adsorption. Both the methods employed were in good agreement with each other favouring maximum inhibition efficiency of 71.81% for MPOD and minimum of 57.64% for PGAZ primarily due the difference in aromatic sites as revealed in mechanism.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effect of polymers at minimum concentrations were evaluated. </LI> <LI> Regression co-efficient close to unity intended best fit with Langmuir adsorption. </LI> <LI> Cathodic inhibition was projected from polarisation technique. </LI> <LI> Increase in R<SUB>ct</SUB> values increased inhibition efficiency. </LI> <LI> Proposed mechanism favoured higher inhibition for aromatic than aliphatic moieties. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A Preliminary Exploration on Component Based Software Engineering

Basha, N Md Jubair,Ganapathy, Gopinath,Moulana, Mohammed International Journal of Computer ScienceNetwork S 2022 International journal of computer science and netw Vol.22 No.9

Component-based software development (CBD) is a methodology that has been embraced by the software industry to accelerate development, save costs and timelines, minimize testing requirements, and boost quality and output. Compared to the conventional software development approach, this led to the system's development being completed more quickly. By choosing components, identifying systems, and evaluating those systems, CBSE contributes significantly to the software development process. The objective of CBSE is to codify and standardize all disciplines that support CBD-related operations. Analysis of the comparison between component-based and scripting technologies reveals that, in terms of qualitative performance, component-based technologies scale more effectively. Further study and application of CBSE are directly related to the CBD approach's success. This paper explores the introductory concepts and comparative analysis related to component-based software engineering which have been around for a while, but proper adaption of CBSE are still lacking issues are also focused.

Uplift Capacity of Single Pile Embedded in Partially Submerged Sand

A. Basha,W. R. Azzam 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.12

This article illustrates experimentally the effect of the groundwater level rising on the soil pile interaction under uplift load. A series of model test for piles embedded in partially submerged sand along pile depth under pull out loads were carried out. A rigid steel cylindrical cell measuring 315 mm inside diameter with 850 mm high was used as a sand container. Investigations were done by varying parameters as the ratio between groundwater height to embedded pile length (hw/L), pile stiffness (L/D), installation method and sand density. Results showed that there is a considerable decrease in the uplift capacity of the piles due to increase in the groundwater level. It has been found that the variation of the submerged pile length ratio from 0 % to 100 % leads to decrease in the uplift capacity as much as 60% of its initial value in dry condition.

Effect of growth temperature on gallium nitride nanostructures using HVPE technique

Munawar Basha, S.,Ryu, S.R.,Kang, T.W.,Srivastava, O.N.,Ramakrishnan, V.,Kumar, J. North-Holland 2012 Physica E, Low-dimensional systems & nanostructure Vol.44 No.9

The growth of hexagonal wurzite one dimensional (1D) gallium nitride (GaN) nanostructures on sapphire substrates using hydride vapor phase epitaxy (HVPE) process was carried out at two different temperatures (973K and 1023K). The GaN nanoneedles were formed at 973K and hexagonal nanorods get formed at 1023K. The morphologies of these nanostructures were studied using high resolution scanning electron microscope. X-ray diffraction and micro-Raman spectroscopy measurements confirmed that the as grown GaN nanostructures are of hexagonal wurtzite structure without any oxide phase. The emission properties of these nanostructures have been investigated using photoluminescence.

Experimental Study on Effect of Recycled Reinforced Concrete Waste on Mechanical Properties and Structural behaviour of the Sandy Soil

Ali Basha,Fatma khalifa,Sabry Fayed 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.6

In recent years, constructing natural aggregates as a base layer for the roads has increased. Natural resources will run out as long as human consumption of them continues. Recycled concrete aggregate (RC) has thus emerged as a substitute material for the building of road base layers. Additionally, RC can be utilized to create interior city highways. The base layer for roads must have sufficient strength to support the working load on the pavement surface without damage deforming. As a result, the focus of this paper is on enhancing the structural performance of sandy soil reinforced with various RC percentages. The three key factors are relative soil density (Dr = 83 and 97%), recycled concrete aggregate reinforcing levels (RC = 0,5,10,15,20,25,30,40,50 and 100%), and reinforcement layer thickness (Rd = 0.0B, 0.5B, B, and 2B where B is the footing model width). Numerous laboratory experiments were conducted in order to examine the impact of important parameters on the properties of the mixtures. The plate bearing tests were carried out using a footing model (250 × 250 mm) inside a tank (1500 × 1500x1000 mm) to ascertain the stress–strain response, bearing capacity ratio (BCR), ultimate bearing capacity, and modulus of elasticity of the tested mixtures. It is clear that raising the RC has no effect on the diameters of the grains. It was found that as RC increased, the mixture's bulk density increased but specific gravity decreased. Maximum dry density rose as RC rose, whereas water content fell. It was noted that BCR unquestionably increased as RC increased for all RC levels and all values of settlement ratios. The appropriate reinforcing layer thickness is suggested to be no more than 2B. As the RC concentration in the sand and Rd increased, the difference between two pressure-settlement curves of densities 83% and 97% significantly decreased. Furthermore, when RC reaches 50%, two curves are roughly comparable. At RC = 50%, it is advised that the relative density of 83% is sufficient to produce the same behavior as the relative density of 97%. It was found that as RC and Rd grew, the tested mixtures' ultimate bearing capacity and elasticity modulus increased as well. A novel proposed formulas are developed to compute bearing capacity ratio, ultimate bearing capacity, and elasticity modulus of the tested mixtures taking into account the influence of RC, reinforcement layer depth, settlement ratio, and the relative density, and its results agree with the experimental results.

Nonlocal strain gradient theory for buckling and bending of FG-GRNC laminated sandwich plates

Muhammad Basha,Ahmed Amine Daikh,Ammar Melaibari,Ahmed Wagih,Ramzi Othman,Khalid H. Almitani,Mostafa A. Hamed,Alaa Abdelrahman,Mohamed A Eltaher 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.43 No.5

The bending and buckling behaviours of FG-GRNC laminated sandwich plates are investigated by using novel fivevariables quasi 3D higher order shear deformation plate theory by considering the modified continuum nonlocal strain gradient theory. To calculate the effective Young’s modulus of the GRNC sandwich plate along the thickness direction, and Poisson’s ratio and mass density, the modified Halpin-Tsai model and the rule of the mixture are employed. Based on a new field of displacement, governing equilibrium equations of the GRNC sandwich plate are solved using a developed approach of Galerkin method. A detailed parametric analysis is carried out to highlight the influences of length scale and material scale parameters, GPLs distribution pattern, the weight fraction of GPLs, geometry and size of GPLs, the geometry of the sandwich plate and the total number of layers on the stresses, deformation and critical buckling loads. Some details are studied exclusively for the first time, such as stresses and the nonlocality effect.

Flexural Behavior of Cracked RC Beams Retrofitted with Strain Hardening Cementitious Composites

Ali Basha,Sabry Fayed,Galal Elsamak 대한토목학회 2019 KSCE Journal of Civil Engineering Vol.23 No.6

In the present research, the efficiency and the effectiveness of different Ultra High Performance Strain Hardening Cementitious Composites (UHP-SHCC) schemes for flexure retrofitting of a cracked RC beams were investigated experimentally, numerically and analytically. The experimental program consisted of six RC beams. The control specimen was loaded until failure. The middle third part of the control specimen was replaced with UHP-SHCC, then, it was loaded again until failure. The other five beams were loaded until 52% of the failure load of the control beam, then they were retrofitted with a layer of UHP-SHCC casted at tension side. The main parameters were thickness and the reinforcement ratio of UHP-SHCC layer with two different lengths of UHP-SHCC layer. The test results showed that using UHP-SHCC layer is a highly effective technique to increase the flexural capacity and the ductility of RC beams. As the reinforcement ratio of the layer increased, the flexural capacity increased. The flexural capacity of the beams with a layer length of 75% beam span was less than the capacity of the beams having a layer length equal to the beam span. Analytical and numerical results agreed with the experimental results.