Study on use of Saw Dust Ash as Replacement of Cement in Concrete

Scientists, Engineers and Technologists are continuously on the lookout for materials which can be used as substitutes for conventional materials or which possess such properties that would enable their use for new designs and innovations. Applications of Concrete alternative materials fall under the first category. The raw materials for making cement and aggregates are essentially limitless, since practically all of earth’s crust can be utilized, if associated costs and energy requirements can be complied with. This course of action cannot be taken as there are other constraints that merit closer examination. The successful utilization of a waste material depends on its use being economically competitive with the alternate natural material. These costs are primarily made up of handling, processing and transportation. The waste materials that can be used in concrete are countless in number. The form in which they are used is wide and variedthey may be used as binder, as a partial replacement of conventional Portland cement or directly as aggregates in their natural or processed states. The stability and durability of products made of concrete using waste material over the expected life span is of utmost importance, particularly in relation to building and structural applications. Keeping all these considerations in mind and taking note of all required standard specifications, wherever possible. our Project aims at creating the confidence of using Waste saw dust ash as high value product in concrete. The project will explore several relevant issues that will be vital when using saw dust ash in concrete. The project will also examine ways to optimize the use of material so that they will offer maximum benefits to the concrete. The project will work out in making concrete industry sustainable. The basic necessity of man after food and water is shelt.


INTRODUCTION
Concrete is defined as any solid mass made with the use of a cementing medium; the ingredients generally comprise sand, gravel, cement and water. That the mixture together of such disparate and discrete materials can result in a solid mass (of any desired shape), with well-defined properties, is a wonder in itself. The word concrete comes from the Latin word "concretus" (meaning compact or condensed), the past participate of "con Cresco", from "com-" (together) and "Cresco" (to grow).
Concrete has been in use as a building material for more than a hundred and fifty years. Its success and popularity may be largely attributed to ➢ Durability under hostile environments (including resistance to water), ➢ Ease with which it can be cast into a variety of shapes and sizes, and ➢ Its relative economy and easy availability Concrete is remarkably strong in compression, but it is equally remarkably weak in tension. Its tensile 'strength' is approximately one-tenth of its compressive 'strength'. Hence the use of plain concrete as a Structural material is limited to situations where significant tensile stresses and strains do not develop, as in hallow (or solid) block wall constructions, small pedestals and 'mass concrete' applications (in dams,) etc. Modern concretes preserve these ancient virtues while greatly extending the range of technically achievable goals. Concrete is used in many different structures such as dam, pavement, building frame or bridge. Also, it is the most widely used material in the world, far exceeding other materials. Its worldwide production exceeds that of steel by a factor of 10 in tonnage and by more than a factor 30 in volume. The present consumption of concrete is over 10 billon tons a year, that is, each person on earth consumes more than 1.7 ton of concrete per year. It is more than 10 times of the consumption by weight of steel.
Scope of current study: -As discussed earlier cement concrete consumes very high amount of virgin materials and it also suffers from some serious problems when exposed to the environment, like sulphate attack. Partial replacement of cement by waste saw dust ash can overcome these problems and yield high performance concrete. The saw dust ash cement on hydration produces practically no Ca (OH)2 & hence is superior to Portland cement. Since most of the research work has not been carried out on Saw dust ash, hence there is a scope of studying the behavior of concrete involving the use of varied percentages of waste saw dust ash.

Objectives of current study: -➢
To explore and assess the possibility of using waste saw dust ash in concrete in terms of its strength. ➢ Recover a wood by product through beneficial use when incorporated into concrete. ➢ To assess the durability of concrete mix. ➢ To Assess the Compressive strength of concrete mix ➢ To have comparative study of workability and change in weight density. ➢ To assess the role of waste saw dust ash as a partial replacement to cement. ➢ To compare the design parameters of waste saw dust ash concrete with plain cement concrete. ➢ To have a comparative study of waste Saw dust ash concrete.

Methodology: -Step1
Initially materials were procured for casting Step2 Cubes of design mix M25 were casted and tested for 7 & 28 days.

Step3
The numbers of cubes for design mix M25 were 6. Step4 Design mix M25 with 8% partial replacement of cement via saw dust ash were casted and tested for 7 and 28 days.

Step5
Design mix M25 with 16% partial replacement of cement via saw dust ash were casted and tested for 7 and 28 days.

Step6
Design mix M25 with 24% partial replacement of cement via saw dust ash were casted and tested for 7 and 28 days.     Ash was then ground after cooling. . Sawdust ash obtained is sieved through IS sieve of 90 micron and the retained material obtained is used for experimentation purposes. Chemical composition of saw dust is presented in TABLE 1. Fig.1 shows saw dust ash added to cement for blending and Fig.2  Testing of saw dust ash: -Cubes were removed from the curing tank. Surface water was wiped off. Cubes were dried for 24 hours. Test cube was placed centrally on the lower plate of CTM. Load was applied without shock and continuously increased at a constant rate.

DATA COLLECTION
Compressive strength was obtained from the ratio of load applied to that of area under impact (P/A).

Conclusion And Recommendations Conclusion: -
As per the results, we observe that the optimum value for attaining maximum strength is around 8% as a replacement of saw dust ash and it was also observed that a 16% partial replacement of saw dust ash attains sufficient strength that falls within the parameter of strength governed by the code (is) and 24% partial repelcaement of saw dust does not any sufficient strength improvements.
On the basis of results obtained, following recommendations can be made: -➢ SDA is a suitable material for use as a pozzolan. ➢ 2.SDA concrete have lower water requirement which implies the more percentage of SDA makes SDA concrete more workable. ➢ Saw Dust can prove economical as its available in large quantities. ➢ 4Use of saw dust ash in concrete will eradicate the disposal problem of saw dust ➢ 5.The compressive strength increases with the curing time and the most recomemded percentage to be used is 8%. ➢ 6.The increase of saw dust ash also shows decrese of strength. ➢ SDA concrete is light in weight so it can also be used in light concreting.