TABLE OF CONTENTS
Title Page
Abstract
Table of Contents
List of Symbols and Abbreviations
CHAPTER ONE
1.0 INTRODUCTION
1.1 Background of the Study
1.2 Statement of the Research Problem
1.3 Justification for the Study
1.4 Aim and Objectives
1.5 Scope and Limitation
CHAPTER TWO
2.0 LITERATURE REVIEW
2.1 History of Earth Materials and Traditional Clay Buildings
2.2 Traditional Methods of Earth Construction
2.2.1 Adobe Blocks
2.2.2 Cob
2.3 Modern Methods of Earth Construction
2.3.1 Compressed Earth Block
2.3.2 Stabilised Soil
2.4 Stabilisation Techniques
2.4.1 Mechanical Stabilisation
2.4.2 Cement Stabilisation
2.4.3 Lime Stabilisation
2.4.4 Bitumen Stabilisation
2.4.5 Gypsum Stabilisation
2.4.6 Pozzolanas Stabilisation
2.4.7 Other Stabilisers
2.5 Hydraform Blocks
2.5.1 Suitable Soil for Soil Cement Block
2.5.2 Tests for Soils
2.6 Compressive Strength of Hydraform Blocks
2.7 Moisture Movement
2.8 Chemical Analysis of SCB
2.9 Durability of Hydraform Blocks
2.10 Deterioration Mechanisms in SCB
2.10.1 Water Related Deterioration in SCBs
2.10.2 Temperature-Related Deterioration in SCBs
2.10.3 Chemical-Related Deterioration
CHAPTE THREE
3.0 EXPERIMENTAL PROCEDURE
3.1 Materials
3.1.1 Properties of Soil
3.1.2 Shrinkage Test
3.1.3 Aggregate Grading (Sieve Analysis Test)
3.2 Properties of Hydraform Blocks
3.2.1 Water Absorption
3.2.2 Wet Compressive Strength Test
3.2.3 Dry Compressive Strength Test
3.3 Chemical Analysis of Cement, Laterite and NPK Fertilizer
3.4 Hydraform Experimental Procedure
3.4.1 Preparation of NPK Fertilizer Solution
3.4.2 Compressive Strength Test after Exposure to NPK Solution
CHAPTER FOUR
4.0 DATA PRESENTATION, ANALYSIS AND DISCUSSIONS
4.1 Data Presentation and Analysis
4.2 Properties of Soil
4.2.1 Shrinkage Test
4.2.2 Result of Aggregate Grading (Sieve Analysis Test)
4.3 Properties of Hydraform Blocks
4.3.1 Moisture Absorption Test
4.3.2 Dry Compressive Strength
4.3.3 Wet Compressive Strength
4.4 Chemical Analysis
4.4.1 Chemical Composition Analysis of Dangote Ordinary Portland Cement
4.4.2 Chemical Composition Analysis of Laterite
4.4.3 Chemical Composition Analysis of NPK
4.5 Compressive Strength Test Results
CHAPTER FIVE
5.0 SUMMARY, CONCLUSION AND RECOMMENDATIONS
5.1 Summary of Findings
5.2 Conclusions
5.3 Recommendations
REFERENCES
APPENDICIES
ABSTRACT
The large number of farmers, especially the rural farmers, make use of NPK fertilizer for farming. These farmers lack adequate storage facilities for storing farm products. This study is aimed at determining the compressive strength of soil cement blocks (SCB) in contact with NPK fertilizer with a view to study the chemical reaction and ascertaining the suitability of the SCB in the construction of ware houses for the storage of NPK. The SCBs were obtained from a Hydraform block firm constructing an estate in Kuje, LGA Abuja. A total of 150 samples of the SCB, the soil used to produce the SCB, obtained from the site in Kuje LGA. The properties of the soil that determines the cement content and properties of the blocks were investigated in accordance with BS EN 771-1:2011 and BS EN 772-1:2011 respectively. The shrinkage has a value of 5.8% and sieve analysis (clay and silt 0.95%) indicates that the cement content can be increased to improve
the strength of the SCB. The wet compressive strength (1.8N/mm2) was 78% of the dry
compressive strength (2.3N/mm2) and less than 80% as recommended by BS EN 772-1:2011. Chemical analysis of the cement, soil and NPK were carried out, a saturated solution of NPK was determined to produce different concentrations. The solutions were prepared and three blocks selected at random were immersed for 7days, 14days, 21days, 28days, 56days and 90days respectively to ensure adequate exposure to the NPK solution. The compressive strength tests shows that the behaviour of the control differs from those in the solution. It was observed that the control experienced leaching of calcium hydroxide from the cement paste with low compressive
strength of 1.64N/mm2. Whereas, the compressive strength of the SCBs in NPK solution was
higher at 7days (1.7N/mm2, 1.74 N/mm2, 2.12N/mm2, 2.13N/mm2, 2.11N/mm2). After 56 days and 90 days, a white layer was observed to form within the SCB exposed to high concentrations of NPK. This was related to the likely ions exchange reaction with calcium hydroxide. The SCB were found to be suitable for use in the construction of ware houses to store NPK fertilizer as long as the selection of the soil and block production was based on standard code and the structure is kept dry from moisture.
