Gehan Abdel Rahman Hamdy

• Professor
• Professor (Full) at Benha University

Rebars fabricated from Fiber-Reinforced Polymers (FRP) are innovative materials utilized as an alternative to traditional steel reinforcement rebars in reinforced concrete structures to overcome corrosion problems especially in harsh and aggressive environments. FRP rebars manufactured from glass or basalt fibers embedded in a polymer matrix have h...

This paper investigates experimentally the efficiency of thermal insulation layers in preserving the flexural capacity of fiber-reinforced polymer (FRP) reinforced concrete beams subjected to elevated temperature. FRP rebars are innovative alternatives to conventional steel reinforcement rebars in reinforced concrete structures. There is a need to...

Temporary houses are an urgent demand for post-disaster condition. These construction systems involve creating modules off-site and assembling them on-site, offering advantages such as reduced construction time and lower costs. Key materials often include Glass Fiber Reinforced Polymer (GFRP) and timber, ensuring durability, resilience, and easy as...

This paper presents an experimental program performed on a structural panel fabricated from glass fiber reinforced polymer (GFRP) and a wooden frame. The tested panel consists of a timber frame with the dimensions of 1200 x 600 x 25 mm covered by GFRP layers which were manufactured by a hand-layup process. Tensile and flexure tests were conducted f...

There is a need to create a new generation of rehabilitation and design processes that integrate performance-based engineering principles. These include evaluating available capacities and structural strength then comparing them to deformation demands related to acceptable performance levels. This paper concerns with structural non-linear static an...

There is a need to create a new generation of rehabilitation and design processes that integrate performance-based engineering principles. These include evaluating available capacities and structural strength then comparing them to deformation demands related to acceptable performance levels. This paper concerns with structural non-linear static an...

This experimental research aims at investigating the possibility of utilizing local glass waste in the production of concrete for construction. Experimental program is conducted to study the effects of using glass powder (GP) obtained by crushing of local glass waste as partial replacement of cement on the fresh and hardened properties of concrete....

This article presents experimental and numerical study of strengthening brick masonry walls loaded with service loads where openings are required to be made, the studied strengthening is made using steel wire mesh or near-surface mounted steel bars. The experimental program consisted of twelve unreinforced brick masonry walls loaded vertically by t...

Explosions caused by standoff charges near buildings have drastic effects on the internal and external structural elements which can cause loss of life and fatal injuries in case of failure or collapse of the structural element. Providing structural elements with blast resistance is therefore gaining increasing importance. This paper presents numer...

Background: Terrorist bombing is currently regarded a threat to almost all countries around the world as it leads to loss of human lives, damage of structures and infrastructure in addition to serious negative impact on security and economy. Being the main carrying elements in skeleton structures, if columns are damaged or collapsed due to blast th...

This paper presents a novel application of artificial neural networks (ANNs) for predicting complete temperature profiles with varying time for circular reinforced concrete (RC) columns exposed to fire. The application is valid for un-strengthened columns or columns strengthened with fibre reinforced polymers (FRP) and isolated with different types...

This paper addresses the efficiency of thermal insulation layers applied to protect structural elements strengthened by fiber-reinforced polymers (FRP) in the case of fire event. The paper presents numerical modeling and nonlinear analysis of reinforced concrete (RC) columns externally strengthened by FRP and protected by thermal insulation layers...

Bars fabricated from basalt fiber-reinforced polymers (BFRP) are a new material used as an alternative to steel bars in reinforced concrete to overcome corrosion problems especially in harsh and aggressive environments. Basalt fibers also have high tensile strength and enhanced durability, in addition to moderate cost. This research investigates ex...

Egypt has a large irrigation network with a huge number of hydraulic structures that were constructed in the nineteenth and twentieth centuries and have an important economical and heritage value. Many of these hydraulic structures suffer from increasing traffic loads, adverse environmental conditions, and lack of maintenance leading to material de...

This paper presents structural strengthening solutions for the rock-cut tunnels and burial chambers of the ancient Serapeum at Sakkara, Giza, Egypt, which date back to the thirteenth century BC. The heritage ancient monument has recently shown severe deterioration, and strengthening was needed to provide support against cracking or falling of some...

This addresses the bond between masonry and near surface mounted steel bars through experimental and numerical investigation. In the experimental program, 12 masonry prisms were prepared from commercial clay bricks and were strengthened using NSM steel bars fixed by cement mortar or epoxy; the prisms were subjected to pull-out testing and the failu...

Самоуплотняющийся бетон – это бетон, который течет и уплотняется под собственным весом без дополнительного воздействия; он имеет особый состав смеси, который обеспечивает высокую текучесть и устойчивость к расслоению. В данной статье представлены результаты исследования, направленного на изучение структурного поведения балок из самоуплотняющегося б...

Fiber reinforced polymers (FRP) strengthening systems are mainly used to retrofit existing and deficient structural members. The performance of such strengthened structures at elevated temperatures is a critical issue that threatens the safety of the structure. Published research includes experimental testing of reinforced concrete (R.C) beams stre...

This research aims to utilize recycled rice straw and rice husk to produce environmentally friendly concrete with optimum properties. An experimental program was conducted which consisted of three phases. Rice straw and rice husk were treated by different methods to obtain rice straw ash (RSA), rice husk ash (RHA) and rice straw (RS) which were use...

This paper presents numerical modeling and structural analysis of a 75-year-old masonry head regulator constructed on an irrigation canal in Egypt. Numerical modeling by finite elements and nonlinear analysis are carried out using commercial software ANSYS. The finite element model represents the current condition including characterization of the...

Wall bearing masonry is the structural system of a considerable portion of residential buildings worldwide. Occasionally it is required to make window or door openings in the loaded walls, which presents a threat to the building safety unless strengthening of the wall is performed before making the required opening. This paper presents testing, num...

Fiber reinforced polymers (FRP) have been widely used in retrofitting and strengthening of deteriorated or deficient reinforced concrete (RC) elements. A major concern about those systems is their performance under elevated temperature which limits the application of FRP for strengthening requirements. Fire protection of the strengthening FRP syste...

Сегодня в строительной отрасли наблюдается значительный интерес к использованию наноразмерных материалов. Исследования направлены на улучшение свойств бетона путем введения наноразмерных добавок. Самоуплотняющийся бетон - это бетон особого состава, уплотнение которого происходит за счет собственного веса без затрат дополнительной энергии благодаря...

This paper presents experimental investigation of the effectiveness of different strengthening techniques applied around openings in unreinforced brick masonry walls. An experimental program is conducted where 18 masonry walls of dimensions 1200x1200x110 mm were built using clay brick units and cement mortar. Different strengthening techniques such...

In recent decades, Fiber Reinforced Polymers (FRP) have shown tremendous potential for retrofitting or repairing existing deficient or damaged concrete structural elements due to their superior properties such as high strength, corrosion resistance and ease of application. However, concern arises about the vulnerability of FRP material to combustio...

This paper investigates the structural response of wide span structures where the primary structural system is cable-stayed roof, and aims at optimizing the design of such structures. Finite element analysis is carried out using commercial software taking into consideration the nonlinear formulation of cables. In order to check the accuracy and cap...

This paper addresses numerical modeling and nonlinear analysis of unreinforced masonry walls and vaults externally strengthened using fiber reinforced polymers (FRP). The aim of the research is to provide a simple method for design of strengthening interventions for masonry arched structures while considering the nonlinear behavior. Several brick m...

In masonry construction, effective bond between mortar and unit is required in order to provide structural integrity and durability to the masonry assemblage. Bond is dependent on material properties, workmanship, curing environment and age. The present research work aims at improvement of the long-term performance of masonry load-bearing structura...

This paper presents numerical modeling and nonlinear analysis of unreinforced masonry walls and vaults externally strengthened by different techniques. The aim of the research is to provide a simple and reliable calculation method to enable the design and structural evaluation of strengthening measures for masonry plane and arched structures. Numer...

Fiber reinforced polymers (FRP) strengthening systems are mainly used to retrofit existing and deficient structural elements. Fire performance is pointed out as a critical factor that requires more research before FRP can be used with confidence in strengthening applications. Specifications and design guidelines limit the use, increase the load fac...

FRP strengthening systems are mainly used to retrofit existing and deficient structural members. The performance of such strengthened structures at elevated temperatures is a critical issue that threatens the safety of the structure. Published research includes experimental testing of reinforced concrete beams strengthened using FRP and subjected t...

Recently, fiber reinforced polymers (FRP) have been widely used in repairing and strengthening of reinforced concrete (RC) structures. In order to increase the acceptance and application of FRP for strengthening requirements, their performance of in case of fire needs more investigation research works. Experimental investigations are required to be...

Unreinforced masonry load-bearing walls constitute the construction system of a considerable percentage of existing residential buildings in Egypt. Rehabilitation of such structures may require making openings of windows and doors in the walls, which decreases the load carrying capacity of the walls and presents threats for the safety of the struct...

Strengthening is often needed to increase the flexural and shear resistance of masonry load-bearing elements. To enable structural analysis and design of strengthening of masonry elements, the structural behavior of such elements should be fully characterized. The stress transfer and the composite action of the strengthened element is achieved by t...

Porous concrete is being used as a pavement system due to its ability to drain, manage and collect storm water, and is thus regarded as a sustainable pavement system. This paper presents an experimental program conducted with the objective of investigating the structural performance of pavements made of porous concrete, as well as exploring several...

Pervious concrete is an innovative approach that is gaining popularity as a pavement material due to its positive environmental aspects. Pervious concrete pavement is used to allow storm water to infiltrate through the pavement and reduce or eliminate the need for additional control structures, in addition to several other benefits. It is thus rega...

Unreinforced masonry arches and vaults are frequent in historic structures worldwide. Many of these structures are subject to deterioration and damage and need strengthening to maintain their stability and preserve the historic value. For design of structural interventions for these structures, analysis is needed to realistically estimate the stres...

Unreinforced masonry is the construction system of most of historic structures and a considerable percentage of existing residential buildings in Egypt. One of the important disadvantages of unreinforced masonry construction is its low resistance to tensile stresses and lateral loads, so there is frequently need for appropriate strengthening for su...

The present research work investigates the effect of elevated temperature on the structural behavior of reinforced concrete (RC) beams strengthened with FRP laminates and protected using different external coating layers.. The first phase of this research consisted of testing 81 concrete cubes protected by different coating materials (cement, perli...

Unreinforced masonry is the construction system in most of the historic structures and a considerable percentage of existing residential buildings in Egypt. One of the important disadvantages of unreinforced masonry construction is its low resistance to tensile stresses and lateral loads, so there is a need for appropriate strengthening. Fiber rein...

One of the important disadvantages of unreinforced masonry construction is its low resistance to tensile stresses and lateral loads, so there is need for appropriate strengthening. Fiber reinforced polymer (FRP) composites have reported in several research work to be effective for strengthening of unreinforced masonry walls and vaults .This researc...

Unreinforced masonry is the construction system of most of historic structures and a considerable percentage of existing residential buildings in Egypt. One of the important disadvantages of unreinforced masonry construction is its low resistance to tensile stresses and lateral loads, so there is frequently need for appropriate strengthening for su...

This paper incorporates both analytical and experimental investigations of the nonlinear behavior of unreinforced masonry assemblages, especially curved elements such as arches, vaults and domes. The conservation of architectural and cultural heritage necessitates going through a comprehensive scientific procedure of assessment of unreinforced asse...

This paper investigates the efficiency of coating layers used for thermal protection of Fiber-Reinforced Polymer (FRP) strengthened Reinforced Concrete (RC) beams. An experimental program was carried out on 36 RC beams protected by using different coating layers of Perlite, Vermiculite, Portland Cement (PC) mortar, clay and ceramic fiber. The teste...

The present research addresses an issue which is a major concern about the use of fiber reinforced polymers (FRP) in retrofit and strengthening applications. This paper presents an experimental investigation of the effectiveness of different fire protection materials and techniques on the efficiency of concrete axial members strengthened by FRP and...

The paper presents a study carried out to restore Sultan Qalawun Mosque that was built in the Fatimids epoch. This magnificent monument was deteriorated structurally and architecturally. The most critical problem was due to differential settlement of the foundations as a result of severe environmental changes. Geotechnical and geophysical investiga...

Fiber reinforced polymer (FRP) materials have widespread use in many different areas of repair and strengthening of RC structures due to their many merits such as low unit weight, excellent corrosion resistance, high strength and ease of handling and application. However, these systems are scarcely applied for enhancing punching shear resistance fo...