P. Alagusundaramoorthy

Bio: P. Alagusundaramoorthy is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Flexural strength & Sandwich-structured composite. The author has an hindex of 12, co-authored 33 publications receiving 437 citations. Previous affiliations of P. Alagusundaramoorthy include University of Kentucky.

Flexural Behavior of R/C Beams Strengthened with Carbon Fiber Reinforced Polymer Sheets or Fabric

Abstract: Their resistance to electro-chemical corrosion, high strength-to-weight ratio, larger creep strain, fatigue resistance, and nonmagnetic and nonmetallic properties make carbon fiber reinforced polym...

Structural Behavior of FRP Composite Bridge Deck Panels

Abstract: Fiber-reinforced polymer (FRP) composite bridge deck panels are high-strength, corrosion resistant, weather resistant, etc., making them attractive for use in new construction or retrofit of existing bridges. This study evaluated the force-deformation responses of FRP composite bridge deck panels under AASHTO MS 22.5 (HS25) truck wheel load and up to failure. Tests were conducted on 16 FRP composite deck panels and four reinforced concrete conventional deck panels. The test results of FRP composite deck panels were compared with the flexural, shear, and deflection performance criteria per Ohio Department of Transportation specifications, and with the test results of reinforced concrete deck panels. The flexural and shear rigidities of FRP composite deck panels were calculated. The response of all panels under service load, factored load, cyclic loading, and the mode of failure were reported. The tested bridge deck panels satisfied the performance criteria. The safety factor against failure varies from 3 to 8.

Ultimate strength of square plate with rectangular opening under axial compression

Abstract: Unstiffened plates are integral part of ship structures, offshore oil platforms, lock gates and floating docks. Openings are provided in these plates for access and maintenance. Provision of opening influences the ultimate strength of plate elements. In this paper the effect of increase in the size of rectangular opening along the loading direction on the ultimate strength is determined using nonlinear finite element analysis. A general purpose finite element software ANSYS is used for carrying out the study. The software is validated for the ultimate strength of unstiffened plate under axial compression. A parametric study is done for different plate slenderness ratios and by varying the area ratio of opening to plate to determine the effect of ultimate strength on the size of rectangular opening. It is found that increase in area ratio along the loading direction decreases the ultimate strength. The variation in ultimate strength varies linearly for plate slenderness ratio less than 2.23 and varies nonlinearly for plate slenderness ratio beyond 2.23 for area ratio ranging between 0.02 - 0.18. Based on nonlinear regression analysis, a design equation is proposed for square plate with rectangular opening under axial compression. Keywords: Unstiffened Plate, Ultimate Strength, Rectangular Opening, Axial Compression, Design Equation DOI: 10.3329/jname.v4i1.913 Journal of Naval Architecture and Marine Engineering 4(2007) 15-26

Experimental studies on through-thickness shear behavior of EPS based precast concrete sandwich panels with truss shear connectors

Abstract: Effective use of building materials for achieving sustainable construction is of prime importance today due to fast depletion of the natural resources by the construction industries for obtaining raw materials and aggregates. Precast insulated concrete sandwich panels (CSPs) consisting of two reinforced concrete wythes, an Expanded Poly-Styrene (EPS) core and truss-type shear connectors can be considered as an innovative construction material for acting as load bearing walls and floors in building systems. The two wythes are connected by the shear connectors through the EPS core for transferring shear forces (henceforth called as through-thickness shear) between the wythes and achieving composite action in the panels. In this paper, details of experimental studies conducted on small-scale precast CSP specimens under through-thickness shear loading are presented. The major parameters considered in the experimental program were the thickness of EPS core, gap between the wythes (in CSPs without EPS core), presence/absence of EPS core and number of shear connector lines. The effect of the major parameters on the failure mode, through-thickness shear strength, load vs relative displacement (between top and bottom wythes) behavior and load vs strain behavior of the CSPs are presented and discussed. The test results indicate that the through-thickness shear strength and behavior of the CSPs are significantly influenced by the parameters considered. Reduction in thickness of the EPS core and presence of the EPS core improved the through-thickness shear strength of the CSPs.

Fiber-Reinforced Polymer Composites: Manufacturing, Properties, and Applications.

Abstract: Composites have been found to be the most promising and discerning material available in this century. Presently, composites reinforced with fibers of synthetic or natural materials are gaining more importance as demands for lightweight materials with high strength for specific applications are growing in the market. Fiber-reinforced polymer composite offers not only high strength to weight ratio, but also reveals exceptional properties such as high durability; stiffness; damping property; flexural strength; and resistance to corrosion, wear, impact, and fire. These wide ranges of diverse features have led composite materials to find applications in mechanical, construction, aerospace, automobile, biomedical, marine, and many other manufacturing industries. Performance of composite materials predominantly depends on their constituent elements and manufacturing techniques, therefore, functional properties of various fibers available worldwide, their classifications, and the manufacturing techniques used to fabricate the composite materials need to be studied in order to figure out the optimized characteristic of the material for the desired application. An overview of a diverse range of fibers, their properties, functionality, classification, and various fiber composite manufacturing techniques is presented to discover the optimized fiber-reinforced composite material for significant applications. Their exceptional performance in the numerous fields of applications have made fiber-reinforced composite materials a promising alternative over solitary metals or alloys.

A critical review of retrofitting methods for unreinforced masonry structures

Abstract: Unreinforced masonry (URM) buildings are common throughout Latin America, the Himalayan region, Eastern Europe, Indian subcontinent and other parts of Asia. It has been observed that these buildings cannot withstand the lateral loads imposed by an earthquake and often fails, in a brittle manner. Methods for retrofitting URM buildings to increase the time required for collapse and also to improve the overall strength widely vary. This review has collated information on various types of retrofitting methods either under research or early implementation. Furthermore, these methods are categorized and critically analyzed to help further understand which methods are most suitable for future research or application in developing countries. The comparison of the different methods is based on economy, sustainability and buildability and provides a useful insight. The study may provide useful guidance to policy makers, planners, designers, architects and engineers in choosing a suitable retrofitting methodology.

Effects of Ratio of CFRP Plate Length to Shear Span and End Anchorage on Flexural Behavior of SCC RC Beams

Abstract: The aim of this experimental investigation is to study the effect of the ratio of carbon fiber-reinforced polymer (CFRP) precured laminate length to shear span and different end plate anchorage systems on the flexural behavior of reinforced concrete (RC) beams cast with self-consolidating concrete (SCC). SCC with a grade of 54 MPa has been used throughout this research to ensure consistent high quality and high concrete compressive strength in all beams and to eliminate the need of any compaction. Ten RC beams strengthened with CFRP plate lengths to shear span ratio of 0, 25, 70, and 85% with and without end anchorages, were tested under monotonic loading. In particular, a single layer of U-wrap sheet and two layers of U-wrap sheets with one layer in the longitudinal direction and the other in the transverse direction were used as end anchorages (double wrap). The results were compared with each other and with those of the same test conducted on an unstrengthened control beam specimen. The load-deflection...

Evaluation of sandwich panels with various polyurethane foam-cores and ribs

Abstract: The objective of this study was to evaluate three potential core alternatives for glass fiber reinforced polymer (GFRP) foam-core sandwich panels. The proposed system could reduce the initial production costs and the manufacturing difficulties while improving the system performance. Three different polyurethane foam configurations were considered for the inner core, and the most suitable system was recommended for further prototyping. These configurations consisted of high-density polyurethane foam (Type 1), a bidirectional gridwork of thin, interconnecting, GFRP webs that is in-filled with lowdensity polyurethane foam (Type 2), and trapezoidal-shaped, low-density polyurethane foam utilizing GFRP web layers (Type 3). The facings of the three cores consisted of three plies of bidirectional E-glass woven fabric within a compatible polyurethane resin. Several types of small-scale experimental investigations were conducted. The results from this study indicated that the Types 1 and 2 cores were very weak and flexible making their implementation in bridge deck panels less practical. The Type 3 core possessed a higher strength and stiffness than the other two types. Therefore, this type is recommended for the proposed sandwich system to serve as a candidate for further development. Additionally, a finite element model (FEM) was developed using software package ABAQUS for the Type 3 system to further investigate its structural behavior. This model was successfully compared to experimental data indicating its suitability for parametric analysis of panels and their design.