Mohannad H. Al-Sherrawi

• Doctor of Engineering
• Faculty Member at University of Baghdad /College of Engineering /Department of Civil Engineering

Using steel jackets around reinforced concrete columns is a widespread technique for static and seismic retrofitting applications. The dimensionless interaction diagrams for reinforced concrete columns strengthened with steel angles are not attempted yet. Thus, this paper presents the formulation of dimensionless interaction diagrams for reinforced...

This study expands the state of the art in studies that assess torsional retrofit of reinforced concrete (RC) multi-cell box girders with carbon fiber reinforced polymer (CFRP) strips. The torsional behavior of non-damaged and pre-damaged RC multi-cell box girder specimens externally retrofitted by CFRP strips was investigated through a series of l...

Six square reinforced concrete flat plates with dimensions of (1500×1500×100) mm were tested under a concentrated load applied on a column located at center of slab. One of the specimens as a reference model without strengthening. Five of specimens were strengthened using steel angles (steel collars) that fixed at the slab-column connection region...

Years of research have been devoted to developing a tool to model and analyze the behavior of rigid pavements. A major component of the new design approaches is the three-dimensional Finite Element Method (FEM), which caused a breakthrough in rigid pavement analysis. The current study used FEM to analyze a rigid pavement composed of a concrete slab...

The design of bridges depends on the transverse distribution characteristics of the live load that is carried. The study goal is to evaluate experimentally and numerically the Live Load Distribution Factors (LLDFs) proposed by the American Association of State Highway and Transportation Officials (AASHTO) specifications for a case of highway bridge...

The purpose of this work was to examine the possibility of employing steel fibres rather of standard shear strengthening, on the shear strength, crack widths and distribution, and flexural strength in concrete beams under repeated loading. When adding steel fibres, it leads to the modification of many properties of concrete, especially tensile stre...

Flexible pavement design and analysis were carried out in the past with semi-experimental methods, using elastic characteristics of pavement layers. Due to the complex interferences between various layers and their time consumption, the traditional pavement analysis, and design methods were replaced with fast and powerful methods including the Fini...

In this study, six square reinforced concrete flat plates with dimensions of (1500×1500×100) mm were tested under a concentrated load applied on a column located at the center of the slabs. One of these slabs was the control specimen, whereas, in the others, steel angles (steel collars) were used, fixed at the connection region between the slab and...

In this paper, the probabilistic behavior of plain concrete beams subjected to flexure is studied using a continuous mesoscale model. The model is two-dimensional where aggregate and mortar are treated as separate constituents having their own characteristic properties. The aggregate is represented as ellipses and generated under prescribed grading...

Fine aggregate (Sand) is a necessary material used in concrete construction purposes, it’s naturally available and it’s widely used around the world for different parts of construction in any building mainly for filling the voids between gravel. Sand gradation is important for different composite materials, and it gives good cohesion when compared...

Concrete is the main construction material of many structures. Exposing to loads creates cracks in concrete, which reduce the performance and durability. The decrease of concrete cracks becomes a necessity demand to ensure more durability and structural integrity of the concrete structure. Autogenous healing concrete is a kind of new smart concrete...

Sampling is the selection of a representative portion of a material, and it’s as important as testing. The minimum weight of gravel field or lab sample depends on the nominal maximum particle size. The weight of the sample will always be greater than that portion required for testing. The approximate precision desired for the testing will control t...

The structural behavior of precast concrete segmental bridges largely depends on the behavior of the joints between segments. In this research, series of static tests were carried out to investigate the behavior of full-scale post-tensioned segmental girders with different types of joint configuration; multi-key joint, single key, and plain key joi...

The live load distribution factors (LLDFs) are typically used to calculate the stress resultants of the individual components from the total shear force and bending moment acting on the entire bridge cross-section. In this study, an evaluation of the LLDFs, suggested by the American Association of State Highway and Transportation Officials (AASHTO)...

A composite steel-concrete beam is constructed from a concrete slab casted on a steel beam and joined together. Under positive or negative bending moment, the slab will behave as the top flange of the composite beam resisting the compressive or tensile stresses. To study the effect of the variation in degree of partial interaction between concrete...

A non-linear three-dimensional finite element analysis, using ANSYS computer program, has been done to study the load-deflection behavior and the load-carrying capacity of a reinforced concrete flat plate built on corner columns. Material non-linearity; such as cracking and crushing of concrete, yielding of steel and plastic deformation of concrete...

A composite beam is made up of a reinforced concrete slab connected to a steel beam by means of shear connectors. If the slab was wide and the composite beam is under positive bending moment, it is evident that the simple beam theory does not strictly apply because the longitudinal stress in the concrete flange will vary with distance from the beam...

A composite beam includes a concrete slab and a steel beam, which are connected by shear connectors. Under positive bending moment, the longitudinal compressive stresses in the concrete slab have a non-uniform distribution along the cross section because of the shear lag effect. In this work a three-dimensional linearly elastic finite element analy...

A composite section is made up of a concrete slab attached to a steel beam by means of shear connectors. Under positive bending moment, part of the slab will act as the flange of the composite beam resisting the longitudinal compression. In this paper a three-dimensional linear finite element analysis, using ANSYS program, is employed to evaluate a...

Composite concrete beams construction separate widely in buildings and bridges for economical purposes. Some international specifications and codes present design rules to predict nominal shear and flexural strength for a composite concrete beam, one of them is ACI 318M-14. The contributions of the concrete slab and composite action to the vertical...

Editorial Board Member of American Journal of Civil Engineering

Concrete is widely used in construction materials since early 1800's. It has been known that concrete is weak in tension, so it requires some addition materials to have ductile behavior and enhance its tensile strength and strain capacity to improve their uses. In this study reactive powder concrete (RPC) was used with steel fiber by using differen...

This paper reports a study of the effects of steel plate diaphragms on shear lag in steel box girders within the elastic range of material property and without including the effect of plate buckling. STAAD.Pro program had been utilized to evaluate and determine top flange stress distribution and the actual effective flanges width in steel box girde...

An experimental investigation is carried out to find the beneficial effect of adding steel fiber to reinforced concrete square columns. Hooked end steel fiber type is used in this investigation. The aspect ratio is 60 and the percentages of the steel fiber that added to the concrete are 0.5%, 1.0% and 1.5%. The experimental work consists of fabrica...

The shear failure in a concrete beam is a brittle type of failure. The addition of steel fibers in a plain concrete mix helps to bridge and restrict the cracks formed in the brittle concrete under applied loads, and enhances the ductility of the concrete. In this research an attempt was made to investigate the behavior and the ultimate shear streng...

Steel fibers have been widely used in the construction industry for the erection of structural members such as beams, columns and slabs to improve their mechanical properties. This paper deals with the torsional behavior of reinforced beams having steel fibers tested under pure torsion. A total of four beams consist of one conventional beam and thr...

In this study, the construction of axial load-bending moment interaction diagrams for a reinforced concrete column and a steel jacket column has been presented. For a reinforced concrete column strengthened with a steel jacket consist of vertical steel sections connected by horizontal steel plates (battens), the axial load-bending moment interactio...

The paper considers the main types of corrosion taking into account the direction of corrosion processes. The main parameters of metal building structures corrosion and factors that have a significant influence on these parameters are taken into account, which can influence the increase of such structures longevity. One of the main factors of corro...

The reinforced concrete column is designed to have a nominal axial resistance. Under different conditions like errors in design, and changing the use of the building from residential to public or storage (extra live loads), the reinforced concrete column will not be able to sustain the desired applied load, and the strengthening is required. This p...

In this paper the analysis of the corrosion basic types destructions on an example of buildings constructions is carried out and the basic requirements to materials for designs in construction are defined. A classification of corrosion damage is proposed, which became a prerequisite for selecting the main indicators of materials that maximally affe...

The work is devoted to the study of the plastics features in modern construction use. The plastics classification in modern construction is generalized. This classification includes: the field of building products application, the features of the materials properties and products, a backup group that includes those products that are not included in...

The structural behavior of Segmental Precast Post-tensioned Reinforced Concrete (SPPRC) beams largely depends on the behavior of the joints that connect between the segments. In this research, series of static tests were carried out to invest igate the behavior of full-scale SPPRC beams with different types of epoxy-glued joint configurations; mult...

Plastic products formation process duration is the important parameter of technological injection molding. For information combination on several parameters of plastic products formation the Venn diagram has been used. The diagram contains the whole set of possible parameters (sample space). Having chosen rational parameters for optimum duration ac...

This paper deals with finite element modeling of the ultimate load behavior of double skin composite (DSC) slabs. In a DSC slab, shear connectors in the form of nut bolt technique studs are used to transfer shear between the outer skin made of steel plates and the concrete core. The current study is based on finite element analysis using ANSYS Vers...

This article is focused on the numerical analysis of the shear resistance at an interface between two concretes cast at different times, which performed by means of a nonlinear finite element program. A linkage element and an interface element had been used, in this study, to model the dowel action and the concrete shear transfer at the interface,...

The effects of the shear lag phenomenon in composite steel concrete beams.

In order to estimate the flexural rigidity of a composite steel concrete beam, it is necessary to study the shear lag phenomenon, which plays an important role in the distribution of the normal bending stresses at the concrete slab of the composite beam. In this paper, a nonlinear three-dimensional finite element analysis is employed to study shear...

The research presents a formulation for optimum design of partially prestressed concrete beams based on elastic analysis. The optimum design is selected to satisfy the limitations of ACI-Code 2014. The objective function is the cost of the beam. The design variables are the cross-sectional dimensions, the area of strands, and the additional ordinar...

This study is conducted to demonstrate the ability of the 3-D representation of the underground reinforced concrete tunnels with the action of the method of construction. Three distinct objectives are considered; the methodology of idealization based on finite element representation, the nonlinear behavior of the system, and the effect of using int...

No attempts have been made in developing the N-M interaction diagram for reinforced concrete columns strengthened with steel jackets using the plastic stress distribution method. Therefore, this paper presents an analytical model to construct the N-M interaction diagram for reinforced concrete columns strengthened with steel jackets using the plast...

Different methods used for repairing or strengthening of RC columns. Strengthening with steel jacket is widely used specially for rectangular and square columns. Many studies have been carried out on this technique; most of these studies did not take the effects of bending moments into consideration. This paper presents analytical models to constru...

The research embraced the utilization of an irregular overview technique to gather master feelings from green improvement specialists in China. A particular concentration was given to development specialists who have at least 5 years in green improvement, either locally or abroad. The group of stars of the green specialists included yet was not lim...

Self-healing concrete is one of the modern smart concretes, which can heal the cracks formed in it by itself. This study aims to develop and apply the using of self-healing concrete as a method for concrete crack reducer, and repair to enhance the properties of concrete.

In this study, a three dimensional finite element analysis was utilized to study the behavior of reinforced concrete T-girders with and without web openings under pure torsion by using ANSYS APDL 15.0 program. Fourteen reinforce concrete T-girders were analyzed; one of the girders (without web openings) was modeled as a control girder. The analysis...

In this study, the effect of the combination of micro steel fibers and additives (calcium hydroxide and sodium carbonate) on the size of cracks formation and healing them were investigated. This study aims to apply the use of self-healing phenomenon to repair cracks and to enhance the service life of the concrete structures. Micro steel fibers stra...

In this study, the effect of the combination of micro steel fibers and additives (calcium hydroxide and sodium carbonate) on the size of cracks formation and healing them were investigated. This study aims to apply the use of self-healing phenomenon to repair cracks and to enhance the service life of the concrete structures. Micro steel fibers stra...

A composite section is made up of a concrete slab attached to a steel beam by means of shear connectors. Under positive and negative bending moment, part of the slab will act as a flange of the beam, resisting the longitudinal compression or tension force. When the spacing between girders becomes large, it is evident that the simple beam theory doe...

Effective Width in Codes of Practice The effective width concept has been widely recognized and implemented into different codes of practice around the world. The formulas used by various codes are shown in Table 1

This paper studies the effects of stiffeners on shear lag in steel box girders with stiffened flanges. A three dimensional linear finite element analysis using STAAD.Pro V8i program has been employed to evaluate and determine the actual top flange stress distribution and effective width in steel box girders. The steel plates of the flanges and webs...

A concrete bridge has been constructed on 1979 at Mosul city. The total length of bridge is 660 m and its width is 20 m. The bridge consists of 10.3 m in length for each. Each span was constructed from box girders supported by 9 columns and ceiling by concrete caps. Due to the defects in maintenance along time, the expansion joints experienced seve...

This study investigates the effect of spacing, shapes and connection of the steel cross frame diaphragms on the deflection of the steel bridges. The bridge under investigation is a simple single span non-skewed girders. The bridge is modeled using finite elements using STAAD.Pro computer program. The validity of the finite element model is establis...

In the present study, a general nonlinear one-dimensional finite element beam model is developed for the analysis of composite beams. The proposed model is based on the partial interaction theory of composite beams where the flexibility of shear connectors is allowed. By using a layered approach for the composite beam cross-section and including th...

Footings are designed such that the plastic collapse of the structure and the soil beneath footings occurs simultaneously. For sandy soil, the footing can be subjected to obvious deformations before the plastic collapse load is reached. This paper investigates the foundation response up to plastic collapse of portal steel frames built on sandy soil...

A two-dimensional interface element with special properties has been developed that can be used to model the nonlinear behavior of the surface between two concretes cast at different times. A proposed shearing stress shear deformation (slip) relationship is utilized to establish the shear stiffness properties of the element. The normal deformations...

To study the nonlinear response of composite concrete beams, a finite element analysis is presented. Material nonlinearities as a result of nonlinear response of concrete in compression, crushing and cracking of concrete, strain softening and stiffening after cracking, yielding of reinforcement, bond-slip, shear-slip, and dowel action between the p...

To study the nonlinear response of composite concrete beams, a finite element analysis is presented in this work. Material nonlinearities as a result of nonlinear response of concrete in compression, crushing and cracking of concrete, strain softening and stiffening after cracking, yielding of reinforcement, bond-slip, shear-slip, and dowel action...

The virtual forces method is used in derivation of the exact fixed-end forces for a nonprismatic member. The strain energy due to bending in a member is used with the actual description of the nonprismatic member geometry. Fixed-end forces for nonprismatic members with linearly varying width, linearly or parabolically varying depth under different...

A cellular plate structure is constructed of top and bottom flanges separated by a combination of longitudinal and transverse webs which may be parallel or nonparallel. Two methods have been presented for the analysis of steel cellular plate structures with nonparallel webs and diaphragms. In the first method, the grillage method, the exact stiffne...