Earthwork Checklist in Building Construction

The first step of building construction is earthwork. Earthwork begins with the soil investigation even before preparing the plan of a building. Then earth filling or cutting is done to make the ground surface even. And then, the land is cleaned. Cleaning involves removing tree roots, existing sub-structure (if any) and any small plant or vegetation from the site. Finally, plot is secured by making fence all around it.

Construction earthwork starts after getting the structural drawings.

Read more: Types of Drawing in Building Construction

The purpose of this article isn't describing the earthwork procedure of construction. I've just given the concept of earthwork procedure so that you don't confused that this checklist is for which earthwork.

This checklist is for the earth work after construction begins. That means, this checklist is for the earth work which we do for the purpose of constructing building's foundation. This checklist is very important as our complete building will stand on this earth.

checklist, earthwork, building construction

Earthwork Checklist in Building Construction

The following check points should carefully be judged during earthwork of foundation -

Services connection: Before starting earthwork make sure there are no services line such as electrical connection, water supply and drainage connection, telephone line etc. below ground.

Benchmark: Mark your desired level in a permanent place. You'll need this mark through the project duration.

Setting layout: Check the setting layout plan carefully so that your building doesn't displace.
Sub-base level of footing: Check the sub-soil level from the bench mark so that you don't have to cut extra soil.

Side-slope in excavation: During earth excavation check that slope is maintained in side-soil.

Base soil: Check the base soil, on which building's foundation will rest, is hard enough. You may consult geotechnical engineer that the base soil is perfect for further work execution.

Excavation area: Check the excavation area is extended beyond the foundation of building for easy moving during work execution.
Cleanign of foundation bed: Check that loose and displaced materials are cleaned from the foundation bed.

Backfill: Check backfill is being done after ending the shutter removal period of footing.
Backfilling material: Try to backfill with the excavated soil. And check the backfilling material is free from large lumps, organic or any other foreign materials. Check all shuttering materials are removed before backfilling.

Check backfilling process: Backfilling should be done evenly on all sides. Check that is being done properly.

Backfill compaction: Backfilling should be done layer by layer. Each layer shouldn't exceed 6 inch thickness. And each layer should be compacted to maximum dry density of soil. Check those are being done properly.

You may also want to read: Earthwork Excavation for UGWT


YOUR TURN:
Do you want to add any related check-point in this list?
Please do that in comments. I'll add those in main article...

6 Ground Works to Prepare a Land for Building Construction

We build our building on a firm ground. We build our building on our land (not on others). We build our building such a way that it'll resist pests. We build our building on the right spot so that it doesn't avoid side-back rules of government or legal authorities.

To ensure all these things we need to do the following 6 ground works even before starting construction.


6 Ground Works to Prepare a Land for Building Construction


  1. Geotechnical investigation
  2. Surveying
  3. Earthwork cutting/filling
  4. Site Cleaning
  5. Pest controlling
  6. Grading and Levelling site

1. Geotechnical investigation: Geotechnical investigation is done to determine the reactivity of soil as well as physical and chemical properties of soil. This investigation is done even before preparing the plan of building. Based on the soil investigation, a geotechnical report is prepared by geotechnical engineers. Geotechnical engineers then design the foundation of building based on this reports.

2. Surveying: Surveying is done to accurately mark-out the boundaries of a land to avoid future legal-dispute after construction begins. It also helps to set-out the building-plan on land exactly where it should be.

3. Earth cutting/filling: To make uneven surface of ground even earth cutting/filling is done. If the surface is above from desired level then earth cutting is done and if the surface is below the desired level then earth filling is done.

4. Site Cleaning: This work involves removing tree roots and other organic matters from construction site. This is very important as tree roots and other organic matters can cause the future settling of earth which will cause for your structure damage.

5. Termite treatment: Not all construction sites require termite treatment. It needs only where there is a possibility of termite attack to a building. This work involves applying termite barrier chemical on ground.

6. Grading and Levelling site: Grading is done to prevent water flowing towards the foundation of building. This is done by making a grade slope away from the foundation of the building.

Levelling is done to make the base of foundation level. Don't be confused with earth cutting and filling. Earth cutting/filling isn't done for levelling purpose. That's done to make the ground surface even.

When you decide to make a building/house on a land, you must go through the ground works discussed above to ensure your building's sustainability.


YOUR TURN:

Do you need termite treatment in your area?

If yes then which chemical do you use for that?

Please share in comment...

Basic Construction Process of RCC Column

RCC (Reinforced Cement Concrete) column is a structural member of RCC frame structured building. It's a vertical member which transfers loads from slab and beam directly to subsequent soil.

A whole building stands on columns. Most of the building failure happens due to column failure. And most of the column failure happens not for design fault but for the poor construction practice. So, it is very important to know the construction process of the RCC column properly.

Constructing RCC (Reinforced Cement Concrete) Column involves following four stages of works -

  1. Column layout work
  2. Column reinforcement work
  3. Column formwork, and
  4. Pouring concrete into column.

RCC column, construction process of RCC column
 

Construction Process of RCC Column


1. Column layout work: In this stage of works the location of columns are determined practically in field. It is done by laying rope according to grids shown in the drawing and then mark the location of columns related to rope.

In drawing, column locations are shown related to grid-line with dimension. Practicaly, in field, ropes are our grid-line. So we place columns related to rope-line by measuring dimension shown in the drawing.

2. Column Reinforcement work: After marking the column locations, we then start to place reinforcement as instructed in the structural drawing.

This is normally described in the drawing like -

C1-12#16 mm⌀ and stirrup-10 mm⌀ @ 4" c/c.
That means column C1 will have 12 numbers of 16 mm diameter bar as vertical bar and 10 mm diameter steel should be placed 4 inch center to center as stirrup.

or

C2-8#20 mm⌀ + 10#16 mm⌀ and stirrup-10 mm⌀ @ (4"+6") c/c.

This C2 column's reinforcement specification means that it'll have 8 numbers of 20 mm diameter bar as well as 10 numbers of 16 mm diameter bar as vertical reinforcement and (4"+6") center to center of stirrups placement means middle-half portion of clear height of column will have 6" center to center spacing of stirrups and upper one-fourth as well as bottom one-fourth height of column's clear height will hold stirrups at 4" center to center spacing.

There is a sheet in structural drawing which contains structural notes from structural designer. In that drawing sheet, you'll find suggested lap length for column's steel of different diameter bar and other important notes. You should read those before column reinforcement work.

3. Column formwork: In building, floor height is normally kept 10 feet. If the slab has beam then we have to pour concrete up to beam bottom level. Suppose, beam height specified in drawing is 1'-6". So, the casting height of our column will be 8'-6". And our formwork height will be 8'-6". But one thing should be considered here is that dropping concrete from above 5' height isn't suggested during pouring. Because it leads concrete segregation. So we should make one-side of column formwork within 5 feet height range. After casting 5 feet of column, we just lift the short side up to full-casting height of column next day.

Another way to cast column without segregation is to keep a small window at 5 feet level of full-height formwork. After casting up to that level, close the window and cast the rest of the column.

4. Pouring concrete into column: Casting column is easy. For small quantity of concrete volume we normally depend on machine-mix concrete and for large concrete quantity we order ready-mix concrete. I would suggest machine-mix concrete. Because, if you use moving pump with ready-mix concrete and if you want not to exceed 5 feet height range for dropping concrete that would be difficult.

If you don't use moving pump, yet there are some problems. Suppose, you have decided to use ready-mix concrete without pump. In that case, you have to manually unload concrete on job site from ready-mix concrete truck and have to manually pour into column. That'll take long time and you'll exceed initial setting time of concrete. As a result, concrete will lose its quality. So it is better to cast column with machine-mix concrete.


YOUR TURN:

How do you cast column?

Do you maintain 5 feet height for dropping concrete?

Do you use any admixture for dropping concrete above 5 feet height for avoiding segregation?

Please share in comments...

Fundamental of Standard Proctor Test

The main purpose of soil compaction is to achieve maximum density of soil. It is done by removing air voids from soil. Removing maximum quantity of air voids isn't possible from fully dried soil. So, it requires to add water to soil for proper compaction.

Standard Proctor test, maximum dry density, optimum water content, soil compaction test

But, it is essential to add certain amount of water to achieve maximum density of soil.

This concept was first introduced by R. R. Proctor in 1933. He showed that, for a given compaction effort, dry density of a soil depends on the water amount of that particular soil. That means, to obtain maximum dry density of a soil, a certain amount of water must be present on that soil.

To determine the required quantity of water to obtain the maximum dry density for a particular soil a test is done in laboratory, that is the standard proctor test.

In this test, a selected soil sample is collected from field and compact into a cylindrical mould at various water contents in laboratory.

The volume of cylindrical mould is 1000 cubic-centimeter. This mould is filled by three layer step by step with the given soil sample. Each layer is compacted by a rammer. This rammer is dropped from a determined height for equal compaction effort.

This procedure is done several times with the soil of different water content. And results are taken for these tests.

All the results are then showed in a graph. In that graph, X-axis shows the water content and Y-axis shows dry density of the sample soil. In between, a curved line is drawn with all of the results of same compaction effort. From that curved line we can determine the required water quantity for obtaining maximum dry density of selected soil with a given compaction effort. See the picture above.

Based on this result, contractors can choose the type and amount of compaction.

But, the problem is that, this Standard Proctor Test doesn't reproduce same result in the field. That's why the Modified Proctor Test is developed for reproducing more accurate result in field. Yet, the Standard proctor test is used in many countries for soil compaction.

YOUR TURN:
Which test method is used in your region? Please share in comments...

A Checklist for Brick Flat Soling

Brick Flat Soling (BFS) is mostly used in building construction and road construction. In building construction, the common use of brick flat soling is in ground and basement as concrete bed. The purpose of using it as concrete bed is to make concrete bed smooth and stable.

The process of making brick flat soling is simple and almost all workers know it well and do it good. That's why it is neglected by most of the site engineers. There is a trend among site engineers to approve BFS work without checking. I know it well because I'm directly related to construction.

Once I asked a site engineer of one of my project that in which direction a frog mark should be placed in BFS. He couldn't answer it. He isn't bad engineer. Even he knows that answer. But instantly he couldn't answer because for long time he has been neglecting this item to check.

But checking should be done properly even if it is a simple work item. Otherwise, workers also will try to neglect that item and you'll be responsible for making low quality structure.

A Checklist for Brick Flat Soling

Following checking should be done for Brick Flat Soling -

Material quality: You already know that the required building materials for BFS are 1st class brick and fine aggregate (sand). Check the quality of those building materials. See:

"Quality Assessment of Some Basic Building Materials"

"6 Requirements of Good Quality Bricks"

Compaction of sub-soil: Bricks are placed on soil or sand bed. Before placing bricks, check that bed is compacted by hand rammer and by sprinkling water.

Levelling of bed: Check the compacted surface of bed is levelled properly. Also check the bed surface is at desired level.

Frog mark (if any): Check the frog mark of bricks are kept upward direction so that it can make bond with future concrete.

Brick joints: Check the bricks are jointed as English bond pattern. See - "Traditional Brick Bond Patterns"

Joint filling: Check the joints are filled with sand. Make sure water isn't being used for flushing sand from brick surface.

Surface level: Check the finish surface level of BFS to make sure it has been made at desired level. Actually we have checked this level during the preparation of bed which I included in the "levelling of bed" point above. This is done for cross checking purpose only.

Checking of Brick Flat Soling is simple and I tried to include all the checking-points in this article.

YOUR TURN:
If I missed anything please share in comments. I'll include that in main post.
 

3 Most Affecting Factors of Soil Compaction

Soil compaction is the process of increasing dry density or unit weight of the soil. It is done by mechanically reducing air content or voids from soil.

Compacting loose soil is a significant part of constructing any civil engineering structures. There are many factors which affect soil compaction. I will discuss 3 most affecting factors of soil compaction in this post.

factors affecting soil compaction

3 Most Affecting Factors of Soil Compaction

  1. Moisture content
  2. Nature and type of soil
  3. Compaction effort

1. Moisture content: The purpose of compaction is to minimize air voids from soil. Dry soil contains more air voids. Adding water to soil helps to compact soil and increases the dry density of soil. Adding a certain amount of water to a particular soil increases the dry density at maximum level. Adding more water to that soil will reduce the dry density of soil. The amount of water content in soil, at which soil obtains its maximum dry density, is the optimum moisture content of that soil.

2. Types and Nature of soil: There are various types of soil which are generally classified by its grain size. As per AASHTO, soil classification can be categorised into 15 groups. Naturally soil is a combination of soil types. This combination of soil types determines the best compaction method to use.

Basically we find three soil groups in nature - Granular, Cohesive and Organic.

Well graded granular soil obtain high degree of dry density. Coarse-grained soil obtain higher dry density than fine-grained soil. But, If small quantity of fines are added to coarse-grained soil, it will obtain higher dry density with same compaction effort. Adding more fines than the required for filling voids among coarse will decrease the dry density of soil.

Cohesive soils contain high quantity of air voids. This soil group requires more water to minimize air voids and therefore the optimum moisture content is high. Adding water makes this soil plastic and requires more compaction effort.

Organic soil cannot be compacted or not suitable for compaction. So, it doesn't require any discussion.

3. Compaction effort: If compaction effort is increased, the maximum dry density of soil increases and the optimum moisture content decreases.

After a certain point soil's dry density doesn't increase with an increased compaction effort.

Beside the factors discussed above, there are some other factors which also affect the compaction of soil. Such as compaction method, Site condition, etc.

10 Must Follow Safety Tips for Construction Site

I was working on United Arab Emirates some years ago. That time I've witnessed an accident in a construction project. A worker was stripping concrete shutter on 8th floor at outside of building. He was fell down due to lack of safety. But he was alive. Everyone were happy including project engineer. After that incident, project engineer gave him 100 dirhams (about 25 dollars) and request him to bring some sweets and feed all who were present.

A speedy car had hit him when he was crossing the road after buying sweets and he died. Everyone were saying that was his fate!

If we analyze that incident from generall point of view, we'll find, there was no fate. When he fell down from 25 meter height, he didn't die because there was a sand stack down. He died on car accident because his mind wasn't stable enough to cross the road after falling down from 25 meter height.

A statistic of calendar year 2011 -

As per "BLS revised 2011 workplace data", there were 738 death of construction worker. The leading cause of deaths on construction sites were falls, followed by electrocution, struck by object and caught-in/between -

Falls - 259 (35% )
Electrocutions - 69 (9% )
Struc by object - 73 (18% )
Caught-in/between - 18 (2% )
- [Source].

So, it is essential to ensure safety in construction site.

 

10 Must Follow Safety Tips for Construction Site

Below are 10 must follow safety tips for a construction site -

1. Place appropriate safety signboard all around the site and where needed.

2. Make safety tray at every six meter height (specially in building construction).

3. Place appropriate signboard inside the project where applicable. Such as danger signboard or symbol on electrical board.

4. Use well insulated cable for temporary electrical connection.

5. Make temporary masonry wall or safety  grill or fence around void areas. Such as lift void, stair void, etc.

6. Make scaffolding with safety net at periphery of building.

7. Keep a fast-aid box at site for emergency.

8. Prohibit smoking inside the project. If not possible, secure a place for smoking.

9. Keep a bucket of sand and a bucket of water always ready for emergency fire fighting. And of-course keep a fire extinguisher ready for use.

10. Make sure individual safety equipments such as safety belt, helmet, etc are properly used by workers when needed.

These are must follow safety tips for any construction site. Beside these, you can regularly train up your workers and team members for making your construction site a safe workplace.

YOUR TURN:
What do you think about safety in construction? Please share in comments.
 

Types of RCC Lintel and Advantage and Disadvantage of Them

Lintel is a structural component of a building. It is made above door and window opening. Its main function is to  support the masonry wall above openings and transfer its load to side walls.

rcc lintel, type of rcc lintel, rcc lintel on wall opening

Material for lintel: Lintel can be made from various materials. Such as steel, wood, stone, RCC, etc.

The most used material for lintel is RCC (Reinforced Cement Concrete). Normally used concrete ratio for RCC lintel is 1:2:4.

Types of RCC lintel: RCC lintel can be two types depending on casting methods: Pre-cast RCC lintel and Cast-in-place RCC lintel.

The procedure of making both types of RCC lintel is almost same. Both have advantages and disadvantages. I personally prefer cast-in-place type of lintel.

Pre-cast RCC lintel: This type of lintel is casted separately somewhere on floor. When wall is ready to place lintel then it is just placed on both sides walls of opening.

Cast-in-place RCC lintel: When wall making is finished up to lintel level then formwork is made on wall for lintel. After making formwork, concrete is poured into it.

Advantage and disadvantage of them:
  • Pre-cast RCC lintel is made on floor. So, we don't need to lift formwork up to lintel level. That reduces required time to make lintel. On the other hand, cast-in-place RCC lintel requires more time to make.

  • As formwork for cast-in-place RCC lintel is made on wall, so it requires to make formwork in three sides. But pre-cast lintel requires only two-side formwork.

  • Cast-in-place lintel requires more supports to hold its formwork in place. On the other hand, pre-cast lintel requires only few supports as it is poured on floor.

  • Pre-cast lintel is cost effective than cast-place-lintel.

  • Surface finishes of pre-cast lintel can be better than cast-in-place lintel.

  • As pre-cast lintel is made separately, so lintel and masonry wall can be done simultaneously.

  • The reason why I prefer cast-in-place RCC lintel is its bond-ability with masonry wall. The bond between cast-in-place RCC lintel and masonry wall is very well. But pre-cast lintel doesn't make any bond with masonry wall.

Construction process of RCC lintel: Construction process of RCC lintel is simple and it doesn't need much technical knowledge. Anyone can make RCC lintel with little construction knowledge.

Generally it contains 4 numbers of 10mm dia bar inside it and stirrup should be 8 mm or 10 mm dia at 6 inch center to center.

Normally, RCC lintel's shape is square or rectangle and it is extended about 6 inch into masonry wall. However, you should follow the construction manual for lintel extension-length into wall, concrete strength and also for reinforcement details.


YOUR TURN:
Which type of RCC lintel do you prefer most and why? Please share in comments.

A Checklist for Quality Plaster Work, Last Part

I tried to keep this plaster work checklist within two posts. But when I start to write it's been too long. So I made the checklist to three parts. This is the 3rd and last part.

Click the below links to read 1st and 2nd parts -
A Checklist for Quality Plaster Work, Part-1
A Checklist for Quality Plaster Work, Part -2

Plaster work checklist for civil construction

"A Checklist for Quality Plaster Work" - Last Part

Smoothness of plaster surface: after plastering check the smoothness of plaster surface. If you plan to fix tiles on plaster then make it scratched.

Level of plaster: check the level of plaster with an aluminium bar. If you need you can use torch light.

Reduce mortar wastage: During plaster work some mortar can be fallen down. To collect them, lay empty cement bag or polythene sheet below. So that you can reuse fallen mortar. These should be collected and reuse every 30 minutes.

Sharpness of Edges and corners: Check all edges and corners are sharp and straight.

Groove and other design work: Check the drawing if there is any groove work or design work on plaster surface. Make the grooving sharp and straight.


Window border: Check the window border with plumb bob or spirit level that those are straight. Check the sharpness of window-opening edges. Check the borders are in right angle.

Window sill: Check the window sill is plain and even.

Water proofing admixture: During outside plastering, make sure water proofing agent is mixed with mortar.

You May Want to Read:

Safety measure: Safety is an important factor in any construction work.  For plastering works following safety measures should be checked -

Strength of scaffolding: During plastering on ceiling and outside, we make scaffolding to stand on. Check the scaffolding is properly made and tied - specially in outside.

Wearing helmet: During outside plastering, check all masons and helpers are wearing helmet.

Electrical wiring: During plastering inside building, we most often use temporary electrical connections for lighting. Check all electrical wire runs above floor level and wires are well insulated. And lights should be hanged on dry wood or bamboo.

I think, I covered every check points of plaster work in this checklist. If I missed anything, please let me know through commenting.

If this checklist helps you, please share with your friends through social networks to help them.

A Checklist for Quality Plaster Work, Part 2

Today I'll share 2nd part of "A checklist for quality plaster work" series. To read 1st part click here.

Check sand quality: Check the fineness of sand as recommended in construction manual. Check sand are dust or dirt free.

Check cement quality: Check the grade of cement as specified in your construction manual.

Cleanness of mortar-mixing platform: Check the platform, on which plaster mortar will be mixed, is properly cleaned. The platform should not be wetted. It should be plain and dry.

Screening of sand: Check sand is screened before mixing with cement. So that any big particles from the sand can be removed.

Cement-Sand Ratio: Check cement and sand ratio is maintained for mixing as recommended in construction manual.

Mortar Mixing: Cement and sand should be mixed in dry condition. Check the dry mix is properly mixed before adding water. There is a tendency of masons to add water before mixing the mortar properly in dry condition.

Water content in mortar: Water content in mix should not be less or more. It should be appropriate as needed.

Mortar using time: Cement's initial setting time is 45 minutes. So, check the mortar is being used within 45 minutes after adding water. If necessary, separate some cement sand mix in dry condition. If you need it later you can add water with that. You can maintain a resister for tracking mortar mixing time.

Thickness of plaster: Suggested plaster thickness is 1/2 inch. But due to size variation of masonry block it can be 3/4 to 1 inch and above. If above one inch thick plaster is required in anywhere that should be done in two coats. After doing 1st coat that should be roughed. And 2nd coat should be done next day.

Lighting availability: When plastering inside a building, check enough lighting is available there.

Make a level mark: Before doing plaster inside a room, make level marks with fresh mortar on all four walls. So that, after plastering room size is truly square or truly rectangular. Otherwise, when you'll fix floor tiles you'll face difficulties.

If you plan to plaster on ceiling, do the same for that also. In this case, make the level mark on beams around the ceiling portion.

I've just finished the half portion of "A Checklist for Quality Plaster work" in these two parts. Last and most important part of this series is here.

So, please click this Email Subscription link to get the update direct in your inbox.

A Checklist for Quality Plaster Work, Part - 1

Before starting plaster work in any of my projects, I do few things -

I visit the overall project once.

I give a short training to my team about plastering. They already know about plastering. I give that for review purpose.

I call all plaster workers (Mason) and give them a short course about plaster work.

And if everything is fine, I finally give permission for plastering.

When I train up my project team I hold a list in my hand. The list contains all the terms that should be checked before and during plaster work. I'll share the elaborate version of that list in this article.

plaster checklist, plaster work checklist,
This list is going to be three parts. In this post, I'll share one of them.


A Checklist for Quality Plaster Work


Curing period: We are always in a hurry to complete projects. So, we have a tendency to start plastering on unmatured surface.
Check the member's curing period is over.

Masonry Joints perfection: If you plan to plaster on masonry surface, check all the masonry block joints are properly filled with mortar.

In this stage, you may want to read - "Checklist for Quality Brick Work".

Masonry joint with RCC surface: Check the cavities between masonry and RCC surface are properly filled with mortar. Specially check the cavity between RCC beam and masonry wall joint.

Services work: Check all services works such as electric piping, plumbing and sanitary piping, air condition piping (if any), etc are completed before starting plaster.

Wire mesh: Check wire mash is provided in masonry and RCC joint and where electrical pipes run and where necessary.

Chipping of RCC surface: Check the RCC surface is chipped.

Tools and materials: Check all required tools and materials for plastering are available at site.

Surface Cleaness: The surface where plaster will be applied should be free from dust, fungus and any loose mortar.

Surface wetness: Check the surface, on which plaster will be applied, is properly watered previous day of plastering so that it doesn't suck water from mortar. But no surface water should be visible on surface.

This is the 1st part of the checklist. Here are 2nd part and 3rd part of this checklist.

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