Design And Construction Of A Precast Concrete Garden Bench

1.0 INTRODUCTION

1.1 BACKGROUND OF THE STUDY
A bench is a long seat on which multiple people may sit at the same time. Benches are typically made of wood, but may also be made of metal, concrete, stone, or other synthetic materials. Many benches have and back rests, although some have arm rests; some have no back rest and can be sat on from either side.

Concrete type of benches is usually positioned on the road side for people to sit; allows room for several people. This bench is used for resting for an interval of time. They can be important to people with mobility impairments (e.g. needs a cane or crutches) who need a place to rest for a couple minutes while traveling on foot. Additionally, benches are often a suitable substitute for everyday activities like eating, reading, etc. when a picnic table is not available.

Concrete benches are very heavy and are a more permanent furnishing. They are often installed in facilities that are not expected to change or transition often, if at all, such as military bases, state parks and official buildings. Concrete is very durable, so it is appropriate for any climate. Concrete can be composed of many different materials to afford benches different accents, depending on what it is composed of.

1.2 PROBLEM STATEMENT
Wooden and metallic bench or any other type of bench is prone to breakage, bending, or rusting and sometimes it can be moved to an unknown place by a stranger. All these disadvantages led to building of concrete bench. Concrete is very durable (it can last for years without breaking), so it is appropriate for any climate (it cannot rust) and also heavy – which makes it too difficult to remove.

1.3 AIM AND OBJECTIVES OF STUDY

The main aim of the study is to build a precast concrete garden benchusing available local materials. The objectives are:

1. To expand the skill and knowledge involved in construction and also to acquire knowledge at the construction of concrete bench
2. To create a place of relaxation in Federal Polytechnic Nekede.

• To enable the student to be self reliance even when they are out at school.

1.4 BENEFIT OF THE STUDY
Here are the benefit of concrete bench:

• Durable construction – concrete offers optimum strength to withstand the rigours of daily use and provide maximum product longevity
• Heavy weight and low recyclable value – meaning the products are far less susceptible to theft than those made of metal.

1.5 SCOPE OF STUDY
The scope of the project covers constructing a precast concrete garden benchwhich composes of MelamineBoard, mortar, and water as the major raw materials used. The work alsodraws, designs and details the concrete seat as well as construct the bench.

1.5 ADVANTAGES OF CONCRETE
Under normal conditions, concrete grows stronger as it grows older. It is the most widely used material (construction) in the world, because it is the only major building material that can be delivered to the job site in a plastic state.

Concrete can be molded into different form or shape due to its unique quality. Other qualities of concrete as a building material are its strength, durability, and economy, depending on the mixture of material used.

Concrete provides a wide latitude in surface texture and colours and can be used to construct a wide variety of structures, such as highways and street bridges, dams, large buildings, airport runways, irrigation structures, breakwaters, piers and docks, sidewalks, silos and farm buildings, home and even barges and ships.

1.6 DISADVANTAGES OF CONCRETE

• Ordinary concrete are much weaker in tension, than in compression.
• Concrete is a bottle material and presses very low tensile strength, limiting ductility and little resistance to cracking
• Internal micro cracks as inherent present in the concrete and its poor tensile strength propagates such micro cracks and eventually leading to bottle failure of concrete.
• Concrete containing micro silica is vulnerable to plastic shrinkage, cracking and therefore, sheet or mat curing should be considered.

1.7  DEFINITION OF TERMS
AGGREGATE: Aggregate in building and construction material sued for mixing with cement, bitumen, lime, gypsum, or other adhesive to form concrete or mortar.

MORTAR: A mixture of cement, sand (fine aggregate) and cement and water.

CONCRETE: A mixture of cement, sand, stone (coarse aggregate) and water.

REINFORCING STEEL BAR: They are used for reinforcement of concrete structures, manufacture of anchor bolts etc.

SUPER STRUCTURE: That part of the structure that is above the ground level.

SUB-STRUCTURE/FOUNDATION: Is the lower portion of the structure usually located below the ground level.