i-manager's Journal on Structural Engineering (JSTE)


Volume 7 Issue 4 December - February 2019

Research Paper

The Effective Cross Frame Geometry and Spacing for Economy in Curved Steel-I-Girder Bridge

Kirankumar Topalakatti*, Santosh M. Muranal**
*Research Scholar, Department of Civil Engineering, Basaveshwar Engineering College (Autonomous), Bagalkot, India.
**Professor, Department of Civil Engineering, Global Academy of Technology, Bengaluru, Karnataka, India.
Topalakatti, K., & Muranal, S. M. (2019). The Effective Cross Frame Geometry and Spacing for Economy in Curved Steel-I-Girder Bridge, i-manager's Journal on Structural Engineering, 7(4), 1-8.

Abstract

The construction of curved composite bridges is common these days in congested city areas, and the additional shear, bending and torsional stress developed due to horizontal curvature are of concern during their design. The cross frames in steel bridge are the secondary load carrying members, which provides the stiffness to the girder and resist the effect of bending and torsion. The selection of cross frame geometry and their spacing is important during bridge design. Presently V shaped cross frames are generally used to connect steel I girders in bridges, but with modification of geometry/shape can result in economic design. Hence, the effects of modified cross frame geometry and their spacing on the performance of curved steel-I-girders bridge is presented here. The modified V types of cross frames are designed and modelled using three-dimensional finite-element method. The structural response is evaluated for combination of vehicular loads of IRC Class A and Class 70R vehicles. The selection of geometry considering proper distribution of stress results in the reduction of cross sections and increase in spacing of cross frames and thus the economical design.

Research Paper

Study on Strength Properties of Light Weight Expanded Clay Aggregate Concrete

Kunchala Ashok*, Tangudu Manoj **
* Assistant Professor (Contract), Department of Civil Engineering, JNTUH College of Engineering, Kukatpally, Hyderabad, Telangana, India.
** Assistant Professor, Department of Civil Engineering, CVR College of Engineering, Hyderabad, Telangana, India.
Ashok, K., & Manoj, T. (2019). Study on Strength Properties of Light Weight Expanded Clay Aggregate Concrete, i-manager's Journal on Structural Engineering, 7(4), 9-16.

Abstract

The Lightweight Aggregate Concrete is usually produced by using natural and artificial light weight aggregate together with mineral and chemical admixtures. In this study, artificially occurring lightweight expanded clay aggregate was used for the development of structural lightweight concrete to reduce both the high self weight and the negative environmental effects that are typically associated with the production of normal Light Weight Aggregate Concrete. The main purpose of this study is to investigate and compare the behavior of lightweight aggregate concrete and normal weight aggregate concrete and also the study focused on influence of the physical properties of the aggregates on strength development. In this research the investigation done about the use of light weight expanded clay aggregate as coarse aggregate in concrete by replacing normal weight aggregate up to 60% by volume along with the steel fibers to 3 produce a Lightweight Expanded Clay Aggregate Concrete (LECAC) and the unit weight in the range of 1600 kg/m to 1800 3 kg/m . The primary aim of the investigation was to reduce both the economic costs and the negative environmental effects that are typically associated with production of light weight concrete containing artificially produced aggregates by taking advantage of India abundant expanded clay resources. LECA is a lighter aggregate with a higher strength when compared to other artificial light weight aggregates, it allows producing high strength, lightweight concrete that can be used in structural systems of buildings. This study also includes the properties of lightweight expanded clay aggregate concrete such as workability of fresh concrete, compressive strength of cubes at 28 days and 90 days, compressive strength of cylinders, split tensile strength of cylinders, flexural strength of prisms at 28 days.

Research Paper

Experimental Study of Properties of Concrete using GGBS and M-Sand with Addition of Basalt Fibre

Pasupuleti Murali Krishna*, K. Rajasekhar**
*PG Student, Department of Structural Engineering, Jawaharlal Nehru Technological University Anantapur, Andhra Pradesh, India.
**Principal and Professor, Department of Civil Engineering, Jawaharlal Nehru Technological University Anantapur, Andhra Pradesh, India.
Krishna, P. M., & Rajasekhar, K. (2019). Experimental Study of Properties of Concrete using GGBS and M-Sand with Addition of Basalt Fibre, i-manager's Journal on Structural Engineering, 7(4), 17-23.

Abstract

The present experimental investigation is to study the effect of replacement of Cement by Ground Granulated Blast Furnace Slaly (GGBS) and FA by M-Sand. The effect of combined replacement by GGBS, M-Sand, and chopped basalt strands on compression strength, split tension strength and young's modules strength of concrete is also investigated. Comparison of the results of tests on Conventional Concrete, and concrete made with partial substitutions & combinations of GGBS, MSand, and chopped basalt strands are done. The durability of concrete is studied through an acid attack test on specimens of both Conventional Concrete and modified concrete. Replacement levels of fine aggregate with M-Sand are 10%, 20%, and 30%. Replacement levels of Cement with GGBS are 10%, 15%, and 20%. The dosage of basalt fibres is 1%, 1.5%, and 2% by weight of cement. The mechanical properties were compared with the control mix for a combination of GGBS (15%), M-Sand (30%), and 1.5% of Basalt Fibre, There is a significant performance improvement of the compressive strength, by up to 21%. A similar trend is observed in the case of Split Tensile Strength (29.5%) and in Flexural Strength (9.2%).

Research Paper

Different Methods for Manufacturing of Translucent Concrete and its Applications

Nadeem Gulzar Shahmir*, Manzoor Ahmad Tantary**
*Research Scholar, National Institute of Technology, Srinagar, Jammu and Kashmir, India.
**Professor, National Institute of Technology, Srinagar, Jammu and Kashmir, India.
Shahmir, N. G., & Ahmad, M. (2019). Different Methods for Manufacturing of Translucent Concrete and its Applications, i-manager's Journal on Structural Engineering, 7(4), 25-32.

Abstract

This paper deals with, how to make translucent concrete using coarse aggregates and how this concrete will act as a useful material for green buildings. In this paper, we also talk about the application of translucent concrete. Translucent concrete is a special type of concrete, which is used in green buildings for the purpose of using light resources efficiently. Green building refers both to create structures and using processes that are environmentally friendly and resourceefficient throughout a building's life cycle. Plastic optical fiber is used for the purpose of the light. The light is one of the most important components we required it through-out the life of buildings. Consumption of electricity is reduced by using translucent concrete. The natural, as well as artificial light resources, are used efficiently. We also study the use of mechanical effects of introducing Plastic Optical Fiber (POF) into concrete. Self-compacting concrete is used in it. We also study how we prepare SCC and what design mix of cement, coarse aggregate, fine aggregate, water-cement ratio, and admixture are required.

Research Paper

Ansys Analysis of High Strength Concrete Beams

H. R. Manjunath*, R. Prabhakara**
*Associate Professor, R V College of Architecture, Bangalore, Karnataka, India.
**Professor-Emeritus at Structural Engineering Division, Visvesvarya Technological University, Belagavi, Karnataka, India.
Manjunath, H. R., & Prabhakara, R. (2019). Ansys Analysis of High Strength Concrete Beams, i-manager's Journal on Structural Engineering, 7(4), 31-36.

Abstract

The knowledge of deformation characteristics is essential for better understanding of basic behaviour of High Strength Concrete (HSC) beams and the mechanism of failure. The large number of investigations was carried out on flexural behavior of HSC beams, but still the major issue of serviceability requirement of the beam is not yet understood properly. The behaviour of HSC is understood over the following headings of cracking moment, load deflection, ductility index, crack width, and ultimate moment carrying capacity. The paper describes the nonlinear Finite Element Modeling (FEM) and analysis of singly reinforced and doubly reinforced HSC beams for flexural behavior. The FEM tool is used to model RCC and calculate the non linear behavior of the structural RCC members. The 8-noded SOLID-65 element was used to model concrete, that can translate in the x, y or z-axis directions and reinforcement were modeled as discrete elements using 3D-LINK8 bar element in the ANSYS. A total of nine beams of M100 grade were modeled of overall size 100 mm X 170 mm and varying effective length so that l/d ration is 15, 20, and 25. All the beams were subjected to two point loading with simply supported condition. The analysis were carried out using IS and ACI codes and compared with experimental values and ANSYS results.

Research Paper

A Graphical Approach to Locating the Control Point of Shear and Flexure over the Span of the Post-Tensioned Beam: Statistical Curve Fitting on the Functions of the Shear Span

S. Kuma*, S. Rajendra**
*Assistant Professor, Jyothy Institute of Technology, Bangalore, India.
**Professor and Principal, Vijaya Vittala Institute of Technology, Bangalore, India.
Kumar, S., & Rajendra, S. (2019). A Graphical Approach to Locating the Control Point of Shear and Flexure over the Span of the Post-Tensioned Beam: Statistical Curve Fitting on the Functions of the Shear Span, i-manager's Journal on Structural Engineering, 7(4), 37-42.

Abstract

An approach is made to compare the basic properties of the two curves plotted on experimental shear strength and geometrical proportion of effective span respectively, over the function of shear span. The illustration is made on the controlling or influencing points of shear and flexure over the span of the beam. Shear stress is the function of the shear span which decreases with an increase in shear span. The graph is plotted on maximum shear stresses ( ) versus shear vu span to depth ratios (a/D) is compared with the graph plotted on ratios of mid-span to shear span (l /2a) versus shear span e to depth ratios (a/D). The dominant positions of shear and flexure are marked by intercepting the tangents on curve [(l /2a) versus (a/D)] at specified points. The influencing position of shear and flexure are compared by a position of cracks e and mode of failure of the beam subjected to two points loading with respective (a/D) ratio.