Comparison Of Locally Excavated Sand With River Sand In Terms Of Strength In Sandcrete Blocks

CHAPTER ONE

INTRODUCTION

The purpose of this study is to compare the compressive strength, durability, cost, and economic importance of sandcastle blocks made from locally excavated sand to those of River Sand. Then, compare the two sandcrete strengths, which will aid in recommending the right give the desired strength for the designed strength for a specific purpose.

NSUDE is a case study in Udi, Enugu West, Enugu State.

1.1  BACKGROUND OF THE STUDY

Sandcrete is a yellow-white building material composed of a binder (Portland cement), sand in an approximate 1:8 ratio, and water. Other ingredients, such as “pozzolanas and rice husk ash,” may be added to reduce the amount of Portland cement. Sandcrete is similar but weaker than mortan, which has a 1:5 ratio.

Sandcrete is typically used as hollow rectangular blocks that are 45cm (18″) wide, 15cm (5.9″) thick, and 30cm (12″) thick, with hollows that run from top to bottom and occupy approximately one-third of the volume of the block.

1.2  STRENGTH AND USAGE

Sandcrete’s final compressive strength can reach 4.6N/mm2, which is significantly lower than concrete’s 40N/mm2. Sandcrete is unsuitable for load-bearing columns and is primarily used for decorative purposes.

a house’s walls

– building a fence

– Septic tank and soak-away tank

– Constructing a generator house.

In Nigeria, measured strength of commercially available sandcrete blocks was found to be between 0.5 and 1N/mm2, well below the legally required 3.5N/mm2. This development could be attributed to the manufacturers’ desire to keep prices low, and because the main cost-factor is Portland cement, they reduce it, resulting in a block that behaves more like loose sand.

SIZES OF SANDCRETE BLOCK

There are numerous types of blocks.

They are used in modern construction and include:

9-inch hollow blocks (450mmx225mmx225mm)
Hollow 6″ blocks (450mmx150mmx225mm)
Solid 6″ blocks (450mmx150mmx225mm)
5 inch solid blocks (450mmx125mmx225mm)
9-inch solid blocks (450mmx225mmx225mm)

1.4  CONSTITUENT MATERIALS OF SANDCRETE BLOCKS

Cement, fine aggregate (sharp sand), and water are examples of these.

1.4.1 CONCRETE

This refers to any adhesive and material used in conjunction with block and is referred to as “hydraulic cement” because the setting and hardening is dependent on the preservation of water. Ordinary Portland Cement is the most common type of cement used in civil construction.

1.4.2 FINEST AGGREGATE

White and colored sand are the two most common types of sand used. The sand contained contaminants such as dust, silt, tree roots, and so on. Sand comes from pits, rivers, and the sea.

1.4.3 WATER

Sandcrete blocks can be formed with any type of water available. This includes water from streams, rivers, and boreholes, among other sources.

1.5  STATEMENT OF THE PROBLEM

Aside from poor mixing ratios, which occur even when some sandcrete block producers add more yield of blocks, other factors can cause blocks to be in poor condition, affecting the quality of the sandcrete produced.

1.5.1 USE OF DEFECTIVE CEMENT

Because of the current economic conditions, some sandcrete block manufacturers opt for very cheap cement, which may not have the required quality to bind a solid block. These blocks break soon after they are constructed. Some cement sellers who have had cement in stock for a long time will sell it to sandcrete block makers at a loss if they notice that the quality of the cement has deteriorated.

1.5.2 CEMENT RE-BAG

Another thing to keep in mind about cement is that some cement sellers Re-bag cement by removing a portion of the cement or placing a low-quality cement product in a bag of a high-quality, trusted cement brand. The method you thought was being used to produce a given quality has been compromised, and it will produce a low quality block that will easily break even before it is used for the project.

1.6 THE OBJECTIVE OF THE STUDY

This project research will help us understand the differences in strength between sandcrete blocks made from locally excavated sand and river sand.
This will also aid in understanding the properties of Nsude sand after laboratory testing.
This will aid us in determining the moulding methods and sandcrete block properties. The ratio of block constituents such as cement, water, and sand determines these properties

1.7 STUDY OBJECTIVES

The scope of this project work is limited to comparing the strength of locally excavated sand to River sand in sandcrete blocks.

(Use as a case study).

1.8 THE STUDY’S SIGNIFICANCE

To better understand the strength of sandcrete blocks made in Nsude from locally excavated sand and river sand.
To assist us in determining the properties of Nsude sand after laboratory testing.

 

 

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