Construction-of-Low-Cost-Houses/C2/Building-Wall-Foundation-using-Bricks/English

Build a foundation using common burnt clay bricks

Title of the Script: Building wall foundation using bricks.

Authors: Dr. Narsingh Varma, Chitra Devi and Madhuri Ganapathi

Key words: bricks, conventional bricks, modular bricks, water, cement, sand, mortar, video tutorial.

Visual Cue	Narration
Slide Number 1 Title Slide	Welcome to this Spoken Tutorial on Building wall foundation using bricks.
Slide Number 2 Learning Objectives	In this tutorial we will learn about, Materials used to build a wall foundation. Classification of bricks. Field Test on bricks. Steps to build a wall foundation using burnt clay bricks.
Slide Number 3 Pre-requisites https://spoken-tutorial.org	To practise this tutorial, learners should be familiar with basic construction methods. For the prerequisite tutorials, please visit this site.
1a.brick mortar and cement 1.Good quality bricks 2.Cement 3.Sand 4.Water 5.mortar 6a. Mortar mixed on concrete floor	Materials required to build a wall foundation are Burnt clay bricks and cement mortar Cement, sand and water are mixed together to make cement mortar.
Slide number 4 Types and characteristics of Bricks	Selecting bricks is an important criteria for brick wall foundation. Let us now see about the types and characteristics of bricks . According to IS code 1077 bricks are classified based on size and strength.
7.Conventional bricks 7a.Conventional bricks2 8.Modular brick 8a.Modular brick 2	Classification of burnt clay bricks based on the size Conventional bricks: size 230 mm x 110 mm x 70 mm 230 mm x110 mm x 30 mm Modular bricks: size 190 mm x 90 mm x 90 mm 190 mm x 90 mm x 40 mm.
9.classification of bricks image	Based on compressive strength bricks are classified into different classes. Brick Class designation is shown in this table.
10.well burnt bricks 11.brick struck 11.brick struck.mp4 12. Brick texture 1.good quality bricks 15. load bearing walls 15a. load bearing walls	Characteristics of good quality well Burnt Clay Bricks Well burnt bricks should be without any cracks. They should give a clear metallic sound when two bricks are struck together. They should have uniform colour, and good texture. Bricks should be of standard size. Brick should have a perfectly rectangular shape with sharp edges. These bricks are good for foundation, load bearing and external walls.
Under Burnt Clay Bricks 16.under burnt bricks	Under burnt clay bricks are dull in colour compared to well burnt bricks. They have low strength and high water absorption capacity.
Over Burnt Clay Bricks 17.overburnt bricks Over burnt clay bricks They are irregular in shape as they get distorted due to over burning. They have non-uniform colour and texture. These are not good for coursed masonry construction.
Slide Number 5 Simple field tests on bricks	Simple field tests on bricks.
18. Weighing brick 18a. Soaking of bricks 18b. Soaking of bricks 18c. Bricks in water 18d. Wipe with cloth 18. Weighing brick Write in base slide as “The formula to calculate water absorption is: 100 (W2-W1)/W1”	Water absorption test It determines the percentage of water absorbed by a brick when soaked in water. Let’s see the procedure of the test according to IS code: 3495-Part 2 Weigh a completely dry brick, let its weight be W1. Immerse the brick in water for 24 hours. Take the brick out of water. Wipe it with a wet cloth to remove traces of surface water. Weigh the brick within 3 minutes of removal from water. Let its weight be W2. The formula to calculate water absorption is: 100 (W2-W1)/W1.
Slide number 6 +7 Permissible Water Absorption of Bricks	Maximum water absorption for bricks of class 12.5 and below is 20% Maximum water absorption for bricks above class 12.5 is 15% Lesser the water absorption, better is the quality of brick. Hence bricks above class 12.5 have better quality. These provisions are according to IS code: 1077
13. Brickfall a 13. Brick fall b 13. Brick wall a- potrait 13. Brick wall b- potrait	Strength Test Drop a brick flat on a hard surface from 1 meter height. A good brick will not break.
Scratch surface of brick with nail. 14. Scratch brick 14a. Scratch brick mp4	Hardness test Scratch surface of brick with nail. Scratch impressions will not be formed on the surface of a good brick.
Slide number 8 Foundation design	Let’s discuss foundation design and preparatory work for construction of a wall. Design wall foundation details given below are according to IS code: 1080
19a. Width of wall foundation 19b. Width of wall foundation 19c. Width of wall foundation 19d. Width of wall foundation 20. Brick work in steps	Base course of brick work for footing B= W+300 in millimeter. Where W is the width of the wall above the plinth. Foundation masonry is done in steps. Minimum thickness at the end is 150 mm. Minimum width of offset is 75 mm. Maximum ratio of step thickness and offset should be 2 Brick work for foundation should start after curing the base concrete. Base concrete curing should be a minimum of 3 days .
7. Conventional brick 8. Modular brick	Minimum foundation width, using conventional bricks: B = 230+300 = 530mm thick Where 230 mm is the length of conventional bricks. Minimum foundation width,using modular bricks: B =190+ 300 = 490mm thick Where 190 mm is the length of modular brick.
Slides Number 9 Mix proportioning of cement mortar Cement mortar mixture 1:3 is used for laying the brick wall foundation. 21. Cement bag 21a. 3 box of sand 21b. Water 21c. Cement water in GI tray 32. Good mortar mix	Mix proportioning of cement mortar Cement mortar mixture 1:3 is used for laying the brick wall foundation. 1 bag of cement, 3 boxes of sand and 15 litres of water. These materials are mixed together in a GI tray. Add more water if needed to make the mortar homogeneous and workable. A good homogeneous mix will have all sand grains coated with cement.
Slide number 10 23. Workplace bricks 24. Lines and pins 24a. Lines and pi 28. Brick wall with plinth 29. Brick wall with proper joint	Construction procedure for laying of bricks. All provisions mentioned are according to IS code 2212 Remove the soaked bricks from the soaking tank and store near the workplace. Fix foundation wall alignment using lines and pins. Foundation masonry should start simultaneously from both ends of the wall. Lay the cement mortar 12 mm thick for a small length and proceed with laying bricks. Do not spread mortar on a full wall at a time. Lay the bricks with frogs downwards. Provide 10 mm thick vertical joints. Joints should be symmetrically staggered in subsequent layers. Immediate layers just one over the other should not have vertical joints in line.
Write on the image as curing 30. Curing 30a.Curing of bricks	Curing Curing must be done by sprinkling water or by covering it with wet hessian cloth. Curing of brick work must be done for a minimum of 14 days.
31. Surface dry bricks 32. Good mortar mix 32a. Headpan with mortar mix 28. Brick wall with plinth 29. Brick wall with proper joint 30. Curing 30a. Curing of bricks	Quality control Bricks being used must be surface dry but fully saturated with water. Mortar must be fresh,workable and homogeneous. Vertical joints of immediate lower or higher course should not be in the same line. All joints must be fully filled with mortar. Mixed cement sand mortar must be consumed before any work break. Regular wetting of masonry must be ensured.
	With this we come to the end of this tutorial. Let us summarise.
Slide Number 11 Summary	In this tutorial we have learnt about, Materials used to build a wall foundation. Classification of bricks. Field Test on bricks. Steps to build a wall foundation using burnt clay bricks.
Slide Number 12 About Spoken Tutorial project	The video at the following link summarizes the Spoken Tutorial project. Please download and watch it.
Slide Number 13 Spoken Tutorial workshops	The Spoken Tutorial Project team: conducts workshops and gives certificates. For more details, please write to us.
Slide Number 14 Forum for specific questions	Please post your timed queries in this forum.
Slide Number 15 Acknowledgement	The Spoken Tutorial Project was established by the Ministry of Education, Government of India.
Slide Number 16 Thank you	This tutorial is contributed by Dr. Narsingh Varma,Chitra Devi and Madhuri Ganapathi from IIT Bombay Thank you for joining.

Contributors and Content Editors

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