The Characteristics of Concrete - Assignment Example

The purpose of this study is to investigate the characteristics of concrete and the methods of optimization of concrete strength. The study will cover the background information about concrete properties as the guideline for the procedure. The next area of study will be the exact procedure, which will be covered in two perspectives, experimental procedure, and analytical procedure. The common knowledge of the strength of concrete materials is that the concrete exists in the hardened state and in the soft (freshly mixed) state. This goes along with the implementation of the curing processes, whose duration of practice varies from between four and ten days of concrete treatment. The study also takes into consideration, the different types of Portland cement from type I to V. In the concrete mix preparation, the strength and consistency of the concrete will be measured. This will enable the engineers to do necessary adjustments to regularize the range of strengths and elasticity.

1. Introduction

From the observations made in the general properties of the concrete mix, it is necessary to take note of the troweling feasibility of using the concrete. In order to ascertain determine whether the troweling is workable or not, the property test will require working with a trowel on the concrete.  The quality of the concrete is measured by how smooth it was to work on it. If it requires so much strength to work on then the trowel workability is troubled and will be assigned either a fair or poor rating. The concrete is produced in different layers, each layer containing a unique composition of materials. The third layer is overfilled for the sake of consolidation. The final stage is to finish the upper layer using the tamping rod as well as the trowel to smoothen it. This is then followed by covering the upper layer to ensure there is no evaporation. Temperature and moisture require careful treatment and observation since they directly affect the strength of the concrete. Before compressing and testing the concrete, one has to take the measurement of the radius and the diameter of the concrete using calipers. The cylindrical concrete is measured in the middle at 4 points on its circumference. Just prior to the testing and compression, the engineers cap each end of the concrete to allow the uniform spread of weight when a load is applied to it.

2. Background

Concretes are made into different shapes and compression failure modes to strengthen them. The shapes include full shear, splitting (columnar), shear cone, cone splitting, and local shear wedge. The variables to be considered during concrete characteristics include the test date, the date of the mix, the design and proportion of the mixture, desired strength of compression, the trowel workability, the greatest load, the greatest compressive strength, and the fracture type. The objective of the experiments is to do the calculation of the average strength of compression on the concrete. This leads to the computation of the highest and the lowest compressive strength on cylindrical concrete shapes, with a uniform proportion of the material mixture. The average compressive strengths for various mixtures and designs will be used to draw the curve indicating the connection between the ratio of water and cement against the compressive strength. The discussion of the curve then follows as expected trend, explaining the influence of the ratio on the compressive strength and eventually showing the ultimate strength of the curve. The curve analysis answers the question of whether the mix designs generated the expected compressive strength and the reasons for disagreement between the average strength of compression in the design and the target of the compressive strengths.

3. Procedures
   • Experimental Procedures

The experiment requires Portland cement of type one, sand, and gravel as the main materials. It also requires lubricant for mold. Testing will be done using rigid end caps and the test machine.

The procedure runs for two lab periods. The first phase involves mixing concrete to design cylinders to be tested. The second session involves the actual test of the cylinders, which goes for 28 consecutive days. The best practice demands a quality choice of proportions for the normal mass and weight of the Concrete. The results will be recorded from every group using various ratios of water to cement to assist in the comparison and data analysis.

• Analytical Procedures

This involves the design of a single batch of compacted concrete as per the directives of the Institute of Concrete in America. The engineers mix adequate concrete to produce test cylinders. The materials are first mixed by combining the right proportion of water, cement, gravel, and sand. The engineer records the weight of each material for analysis. The consistency is then measured using the slump cone equipment.