Experimental and Analytical Investigation of Hollow Core Slab Using Light Weight Concrete

Experimental and Analytical Investigation of Hollow Core Slab Using Light Weight Concrete

Lekshmi Soman1, Asha Philip2

1PG Scholar, 2Assistant Professor,

Sree Buddha College of Engineering, Sree Buddha College of Engineering, Pathanamthitta-689625 Pathanamthitta -689625

Abstract: Concrete plays a major role in the construction field. In building construction slab is one of the largest and important structural member consuming concrete. Slabs in building mainly support dead load and live loads .Concrete slab use more concrete than requirement, hence has to be optimized. So reduce the concrete in centre of the slab by providing various openings.

This paper mainly aims to compare the structural adequacy of hollow core slab using high strength light weight concrete.Light weight structural concrete is an enhanced version of concrete, with emphasis on decrease in density of concrete. It keeps the structure light weight by providing adequate strength.The objective of this thesis work is to demonstrate the flexural behaviour and also to compare the void ratio of hollow core slabs with various openings(circular,square,diamond) using light weight concrete.

Keywords: Hollow core slab, High strength light weight concrete, Flexural Behaviour

1.INTRODUCTION

Concrete slabs are rigid structures typically made of concrete with a small height compared with the other dimension. Slabs in building mainly support dead load and live loads. Reducing self weight of slabs is necessary in order to reduce the total cost of structures. One of the alternatives is to use hollow core slab. Prestressed concrete hollow-core panels have been widely used throughout the world in concrete and steel structures, including buildings, parking structures, and bridges. One of the most common uses of these elements is in floor systems, where precast prestressed concrete hollow-core panels are used together with a cast-in-place (CIP) concrete topping to form a load-resisting composite floor system. Light The study is limited to

• Hollow core slab with circular, rectangular and diamond opening.

• Light weight concrete material (M40 grade)

• Two point loading

  1. LITERATURE REVIEW

     This chapter gives a brief review of previous studies conducted in field of hollow core slabs.

     Nanang Gunawan Wariyanto, Yanuar Haryant, Gathot Heri Sudibyo studied the flexural behaviour of precast hollow core slab using PVC pipe and Styrofoam with different reinforcement. This study discusses the flexure behaviour of precast hollow core slab with different types of reinforcements.

     Haryanto,Gathot Heri Sudiby Hollow core slabs are commonly used in different types of structures. They usually include a 50-mm concrete topping. Structural engineers can use this topping to increase the slab load-carrying capacity. North American design standards relate the horizontal shear

     weight structural concrete is an enhanced version of concrete, with emphasis on decrease in density of concrete. When structural concerns require a minimum to the dead load, light weight concrete is used. It is ideal for roof deck repairs, stair pan fill, elevated floor slabs or over lays on existing floor decks .Since it is light weighted it is ease in lifting and carrying which is an important advantage of light weight concrete. It also offers slower temperature transfer rates than standard concrete, resulting in improved insulation fact. In this study, a new hybrid construction of hollow core slab-type members, in which a hollow core slab of high strength light weight aggregate concrete are used inorder to examine their structural adequacy.

     1. OBJECTIVES

• To compare the performance of hollow core slab with M40 grade concrete and high strength light weight concrete

• To check the performance of hollow core slab with different shape of openings

• To plot and compare the load deflection curve of hollow core slab with different shape of openings using M40 grade high strength light weight concrete

• To validate the experimental result using ANSYS.

  1. SCOPE

     strength at the interface between hollow core slabs and the concrete topping to the slab surface roughness. This paper presents the results of four push-off tests on hollow core slabs supplied by two manufacturers and roughened using a conventional steel broom.

     Eray Baran Results of a study focusing on the flexural response of precast prestressed concrete hollow-core slabs with cast-in-place concrete topping are presented. The experimental part of the study included load testing of five precast concrete hollow-core units. The numerically determined flexural response of test specimens was later compared with the experimentally obtained behaviour.

     Ronglan Zhang Basic assumptions are proposed for the continuity model of a tubular hollow slab combined with continuity analysis and calculation of a finite-element model; the continuity Equation of a tubular hollow slab at the minor axis supported at two ends of the hollow axle under a vertical even load is determined and solved.

  1. METHODOLOGY

In the present study, the experimental program is conducted to compare the flexural behaviour of hollow core slabs with different openings .Concrete cubes are casted by M40 grade concrete and high strength light weight concrete. An RC slab is designed to investigate the load deflection behaviour of RC beam using the mix which gives the optimum strength. The experimental investigation is to be validated using ANSYS software. The properties of the constituents in concrete such as cement, fine aggregate, coarse aggregates are determined. The properties should conform to recommendations given in IS codes. Mix design of M40 grade concrete and M40 grade light weight concrete is prepared by using the material properties. RC hollow core slab is to be designed with the M40 mix. Dimension of hollow core slab is1m×1m×0.12m

A. Mix Design Table 1

Slump Values for Various Super Plasticizer Percentage

Table II

Mix Proportion- Trial Mixes

Table III

Final Mix proportion for M40 grade concrete

1. RESULTS

   Test on Hardened Concrete

   Compressive Strength Values Obtained For M40 Control Mix

   Fig.1 Compressive Strength Test on cube

   F

   Fig.2 Flexural Strength Test on Beam

   Fig.3 Split Tensile Strength Test on Cylinder

   Table IV

   Compressive Strength of Hardened Concrete Cubes

   Table V

   Flexural strength on hardened concrete

   Table VI

   Split Tensile strength of hardened concrete

   Table VII

   Mix Proportion by Varying Percentages of Metakaolin

   Table VIII

   Effect of Metakaolin on Compressive Strength of Concrete

   Fig.4 Graphical Representation of Cube Compressive Strength of Various Mixes with Age

   Table IX

   Mix Proportion for M40 Grade Light Weight Concrete-Trial Mix

2. CONCLUSIONS

• Priliminary investigation of coarse aggregate, fine aggregate, cement and Leca aggregate were carried out

• Mix design of M40 and M40 light weight concrete

• Optimum of super plasticizer0.75%

• Optimum of metakaoline20% of cement

  • From the trial mix full replacement of coarse aggregate is not possible in order to get a high strength concrete

ACKNOWLEDGEMENT

I am thankful to my guide,Asst.Professor.Asha Philip in Civil Engineering Department for her constant encouragement and able guidance.also thank my parents.friends etc for their continuous support in making this work complete

REFERENCES

1. [1] Nanang Gunavan,Wariyant no,Yanaur Flexural Behavior of precast hollow core slab using PVC and Styrofoam with different types of reinforcement(2016)journal of structural and sustainable engg.

2. [2] Haryanto,Gathot Heri Sudibyo Analytical modeling of the interface between lightly roughened hollow core slab and cast in place (2015) ,Engineering Structures.

3. [3] Thersita Herni Setiawan,Bryen Adryfen Risk analysis and priority determination of risk prevention using failure mode and effect analysis method in the manufacturing process of hollow core slab(2016),Engineering structures

4. [4] Daniel Delima Araujo,Mared William Reis Sales Headed steel stud connectors for composite steel beams with precast hollow core slab with structural topping(2016)

5. [5] Eray Baran Effects of cast in place concrete topping on flexural response of precast concrete hollow core slabs (2015)

6. [6] Pradeep Kanakeri, S.Surya Prakash Experimental evaluation of bonded overlay and NSM GFRP bars strengthening on flexural behavior of precast prestressed hollow core slab(2016)

7. [7] Abdolerza Ataeo,Mark A Bradford Finite Element Analysis of HSS semi-rigid composite joints with concrete slabs and deformable bolted shear connectors(2016) http://www.scirp.org/journal/eng

8. [8] Asham Adawi,Maged A Yousef Evaluating interfacial shear stresses in composite hollow core slab using analytical solution(2016) http://www.scirp.org/journal/eng

9. [9] Ronglan Zhang Equivalent Rigidity at the Minor Axis of Concrete Hollow Slab Based on Continuity Analysis (2015)Engineering Structures

10. [10] Aiham Adawi , Maged A. Yousef , Mohamed E. Meshaly Finite element modeling of composite hollow core slabs (2015)ASCE