// // 1 comment

Essential Safety for a Building Construction Site

We often see news about construction-accidents in newspaper. Some accidents are happened due to design faulty, some are for construction faulty and some are for the lack of safety measures in construction site.

Now-a-days, "Safety First" has become a slogan in construction industry. Because more construction accidents happen due to lack of construction-safety than other reasons. In the high-rise building construction the situation is more worst. So, in this post I will share the essential safety measures for building construction.
construction safety

Following are the essential safety measure for a building construction project -
  • Safety Signboard
  • Safety tray
  • Individual safety
  • Void area safety
  • Fire safety

 

Safety Signboard

You might have seen various signboards inside and outside of a construction project. Those are safety signboards.

Signboards can contain symbol/sign or tagline or both. These are placed in two locations - outside of project and inside of project.

Taglines used in outer signboard are -
  • Be careful, construction is going on
  • No Parking
  • Sidewalk, etc.

Inside signboard can have the following tagline -
  • No Smoking area
  • Be careful, void ahead
  • Danger (on electrical board) etc.

Safety tray

After casting a floor slab, the edges of its totally unsecure. We make columns and continue the curing process on that slab. During this work process anyone can fall down accidentally. Moreover, we have to move shuttering materials and building materials on that unsecured floor. So, anytime anything can fall down and hurt passers-by.

To protect these it is essential to make safety tray all around the building on every 3 floor.
Safety tray is made with CI Sheet and MS Angle. The width of safety tray is generally made 8 feet width.

Individual safety

Safety helmet, safety belt, safety shoes, safety goggles, hand gloves, etc are individual safety equipments.

Workers should wear helmet during removing beam or slab shutter or when needed.
If workers are working on outside maccha or anywhere where there is a possibility to fall down, they must wear safety belt.

Every construction workers should wear safety shoes.

During welding work worker must wear safety goggles.

Workers also wear hand gloves when they need to do that.

Void area safety

There may have many voids in a building. Such as lift void, sanitary duct voids, electrical voids, and other architectural voids. These voids should be secured by making temporary masonry wall.

Fire safety

Fire is a major factor for construction accidents. Control smoking inside project strictly. This is the major cause for fire. Hang on "no smoking" signboard where needed. Keep a bucket of sand and a bucket of water ready for emergency. And also keep a fire extinguisher in project.

Special situation demands special safety measure. Such as when you work with brand, hoist and any other heavy equipments and machineries, check them if they are safe for work. If you are going to work inside underground water tank, check first that enough air flow is available there.

Keep a first aid box in project to treat preliminary accidental injuries.


YOUR TURN
If you have anything to share please do it in comments...
Read More
// // 14 comments

7 Tests to Justify Brick Quality


To know the quality of bricks following 7 tests can be performed. In these tests some are performed in laboratory and the rest are on field.
  1. Compressive strength test
  2. Water Absorption test
  3. Efflorescense test
  4. Hardness test
  5. Size, Shape and Color  test
  6. Soundness test
  7. Structure test

    brick test,

Test to Justify the Qualities of Brick

1. Compressive strength test

This test is done to know the compressive strength of brick. It is also called crushing strength of brick. Generally 5 specimens of bricks are taken to laboratory for testing and tested one by one. In this test a brick specimen is put on crushing machine and applied pressure till it breaks. The ultimate pressure at which brick is crushed is taken into account. All five brick specimens are tested one by one and average result is taken as brick's compressive/crushing strength.

2. Water Absorption test

In this test bricks are weighed in dry condition and let them immersed in fresh water for 24 hours. After 24 hours of immersion those are taken out from water and wipe out with cloth. Then brick is weighed in wet condition. The difference between weights is the water absorbed by brick. The percentage of water absorption is then calculated.

The less water absorbed by brick the greater its quality. Good quality brick doesn't absorb more than 20% water of its own weight.

3. Efflorescense test

The presence of alkalies in bricks is harmful and they form a gray or white layer on brick surface by absorbing moisture. To find out the presence of alkalis in bricks this test is performed. In this test a brick is immersed in fresh water for 24 hours and then it's taken out from water and allowed to dry in shade.

If the whitish layer is not visible on surface it proofs that absence of alkalis in brick. If the whitish layer visible about 10% of brick surface then the presence of alkalis is in acceptable range. If that is about 50% of surface then it is moderate. If the alkalis's presence is over 50% then the brick is severely affected by alkalies

4. Hardness test

In this test a scratch is made on brick surface with a hard thing. If that doesn't left any impression on brick then that is good quality brick.

5. Size, shape and color test

In this test randomly collected 20 bricks are staked along lengthwise, widthwise and heightwise and then those are measured to know the variation of sizes as per standard. Bricks are closely viewed to check if its edges are sharp and straight and uniform in shape. A good quality brick should have bright and uniform color throughout.

6. Soundness test

In this test two bricks are held by both hands and struck with one another. If the bricks give clear metallic ringing sound and don't break then those are good quality bricks.

7. Structure test

In this test a brick is broken or a broken brick is collected and closely observed. If there are any flows, cracks or holes present on that broken face then that isn't good quality brick.

YOUR TURN:
Which test/tests do you perform most to know brick's quality?

Read More
// // 2 comments

Types of Bricks

It is essential to know the types of bricks for properly understanding the masonry work. Bricks can be many types depending on its quality, making process, its raw material and purpose of their using. In this post I'll describe the brick types for various criteria.

brick type

Types of Bricks Based on Quality

Depending on quality, bricks are three type -

  • First class brick
  • Second class brick, and
  • Third class brick.

First class brick: These bricks are made from good quality raw materials. Color of first class brick is uniform. These are regular in size and shape and doesn't absorb more than 20% water of its own dry weight when immersed in fresh water for 24 hours. The crushing strength of this type of brick should be 105 kg/cm2.

Read More:
6 Requirements of Good Quality Brick
3 Most Important Properties of Brick

Second class brick: The quality of bricks of this type is little bit less from first class brick. Such as it can be slightly over burned. The size and shape can be slightly differ from standard. The crushing strength of this brick-type should be above 70 kg/cm2. These bricks don't absorb more than 22% water of its own weight after 24 hours immersion in fresh water.

Third class brick: This type of brick isn't uniform in size and shape. It can be over burnt or under burnt. It doesn't absorb more than 25% water of its own weight when immersed 24 hours in fresh water. Crushing strength of this type is more than 30 kg/cm2.

Read More:
How to Soak Bricks for Masonry Wall Construction?

Types of Bricks Based on Raw Materials

Depending on raw materials used for making bricks, it can be following types -

  • Burnt clay brick
  • Fly ash clay brick
  • Concrete brick
  • Sand-Lime brick
  • Fire clay brick

Burnt clay brick: This type of bricks are usually made from clay by burning. These are the common type of bricks for construction work.

Fly ash clay brick: When fly ash is mixed with clay for producing brick that is fly ash clay brick.

Concrete brick: The main raw materials for this type of bricks are cement and sand. It is also called mortar brick.

Sand-Lime brick: Lime is used instead of cement with sand for producing this type of bricks.

Fire brick: This type of bricks are made from fire clay. These bricks can tolerate high temperature without distortion and cracking. That's why it can be used in fireplaces.

Types of Bricks Based on Using Location

Depending on using location, bricks can be two types -

  • Facing brick, and
  • Backing brick.

Facing brick: This type of bricks are used on the surface of backing wall. These are high quality and shows various texture on their surface.

Backing brick: These type of brick doesn't contain any texture on its surface. It works as backing support of facing brick.

Types of Bricks Based on Weather Resisting Capability

Depending on weather resisting capability bricks are three types -

  • Severe Weather grade (SW)
  • Moderate Weather grade (MW)
  • No Weather grade (NW).

Severe weather grade: This type of bricks can withstand against repeated freeze-thaw actions. These are useful for the countries where severe freeze-thaw actions happened.

Moderate Weather grade (MW): This type of bricks can be useful for hot-weathering affected countries where freeze-thaw action doesn't happen much.

No Weather grade (NW): This type of bricks are general and it doesn't have any weather resisting capability. It's mostly used in interior wall.

Types of Bricks Based on Purpose of Their Using

Purpose of their using bricks can be following types -

  • Common bricks
  • Engineering bricks.

Common bricks: This type of bricks are used for general purpose with no special requirements. Walls that are made with this type of bricks should be plastered.

Engineering bricks: This type of bricks are burned at extremely high temperature to form a strong and dense product. It has excellent load bearing capacity and high damp-proof capability.


YOUR TURN:
How many types of bricks you used for your construction work?
Please share your remarks in comments...
Read More
// // 1 comment

3 Most Important Properties of Brick

Brick has many good properties which make it most popular building material in the industry. Common brick properties are -

  • Strength
  • Absorption
  • Weather resistance
  • Fire resistance
  • Wear Resistance
  • Porosity
  • Efflorescence
  • Sound Insulation
  • Thermal Insulation
  • Durability
  • Aesthetic Look, etc.

Among them following three are most important properties of brick.

Brick properties, Important properties of brick

3 Most Important Properties of Brick

  1. Strength
  2. Absorption
  3. Weather Resistance

Strength: Brick has good compressive strength which makes it popular in construction world. The compressive strength of brick can vary from 3 N/mm² to 40 N/mm² depending on raw materials used for making brick, manufacturing process and size and shape of brick.

But brick masonry wall strength isn't only depends on brick strength. It also depends on mortar strength, bond quality between mortar and bricks. Bond quality depends many things. Such as brick textures, mortar quality, absorption and workmanship. So, the brick masonry wall strength may not be same as brick strength.

Absorption: Dry brick absorbs too much water from mortar. It's why the mortar cannot be cured properly and develop weak bond-strength. So brick should be soaked properly before masonry work (See: How to Soak Bricks).
The mechanism of bond between bricks and mortar is that fresh mortar absorbs into surface pores of brick and develop bond. If the brick is moistened in such a way that it lost its absorption capability then it cannot absorb mortar paste and develops weak bond. So we suggest to remove bricks from soaking tank one hour before starting masonry work so that it can regain its absorption capability of surface.

Read More: Traditional Brick Bond Patterns Used in Masonry Wall Construction

Weather Resistance: Brick is made from clay and it's burned at high temperature which capable it to withstand severe weathering impact. Only one weathering effect which affects the masonry wall most is the freeze-thaw action. Resisting it almost depends up on the resisting capability of water penetration of bricks.

Preventing water penetration is also depends on the good workmanship. It is said that a masonry wall made by good workmanship can resist water penetration during a storm lasting 24 hours accompanied by 80 to 100 km per hour wind velocity.

Most of the time it is found that water penetrates through mortar joint between bricks and around window and door frame. So, tooling mortar joints and caulking around window and door frames properly can prevent the water penetration to highest level.

Read: How to construct masonry wall?


YOUR TURN:
Did I miss anything? Please share in comment...
 
Read More
// // Leave a Comment

How to Locate Pile on Plot and Protect Them from Missing?

When the bearing capacity of upper level soil is not enough to resist the load then pile foundation is designed. It is a deep foundation (See: Type of Foundations).

The basic function of pile is to transfer loads to hard layer of soil under ground.

On top of piles, pile-cap is constructed to spread the loads among piles. On a pile cap, there can be one or more columns.

Where a pile should be and distance among piles under a pile cap, all these things are considered and designed by structural engineer. As per pile location, a structural engineer designs the reinforcement of that pile cap. If a pile is misplaced the reinforcement of pile cap will lose its functionality. So, care should be taken during locating the piles.

Locating pile is easy. You just have to be cautious so that no pile is misplaced.

Process of locating piles on plot

In foundation layout of structural drawing, there will be grids on both directions. These grids are shown in the drawing like 1, 2, 3... and A, B, C... etc. Mark these grid points on each sides of plot as shown on drawing. Make these marks unmoveable.
Pile Layout
Why we need to mark these grid points on plot for locating pile? Because pile locations are shown in the drawing in reference with grid line.

When we completed marking grid-line points on plot now it is easy to locate the pile locations. In drawing you'll see every pile distance is shown either from grid line or from another pile.

  • Now locate the pile on plot as shown on drawing. Put a steel peg on the centre of pile. Steel peg can be 10 mm or 12 mm diameter bar and 6 to 8 inch long.

  • Fix the steel peg by pouring concrete around it. So that it can't be displaced.

  • Do the same for rest of the piles.

Locating piles after construction is started

Under a pile cap, there can be many piles and one technical term we should always remember that within minimum 10 feet distance we shouldn't bore another pile in same day. But one or more pile can exist within 10 feet as designed. So after casting one pile we maintain minimum 10 feet distance for starting another piling work for the same day. That's why, there is a possibility of missing in-between pile/piles if you don't track properly.
 


How do we track piles during construction?

We make a copy of pile-layout drawing.
Numbering all pile from 1st one to last one by 1, 2, 3... Like this if not numbered previously on drawing.

After casting one pile just mark the pile number on that drawing (see the image above). In this way we can easily find out which pile have been completed and which one not as well as how many piles have been completed at a glance.

If you follow this tactics no pile has been left uncompleted.


YOUR TURN:
How do you track pile during construction? Please share...

 
Read More
// // 5 comments

How to Soak Bricks for Masonry Wall Construction?

Soaking bricks is must for quality masonry works. But the questions are -

  • What is soaking?
  • Why should we soak bricks?
  • How long should bricks be soaked?
  • How to soak bricks?

Soaking bricks, masonry work

What is soaking?

Most of us think that making bricks wetted is the soaking. As per dictionary.com, Soaking is to make something saturated with water. To make bricks saturated with water is called brick soaking. Our purpose is not to make bricks wetted but make it saturated with water.

Why should we soak bricks?

Bricks are dry and they absorb too much water. If we don't soak bricks it will absorb water from cement-mortar. As a result, mortar will be weak and fail to make bond between bricks due to lack of enough water for hydraulic reaction of cement in mortar. Ultimately it'll weaken the masonry wall. So it's very essential to soak bricks properly.

Another purpose of brick soaking is to bring out salt and any other harmful chemicals from the bricks.

How long should bricks be soaked?

It is a common tendency to make bricks wetted by spraying water. That is harmful for quality brick work. Bricks should be completely saturated with water. It should be soaked untill it doesn't absorb single drop of water. Normally it takes 8 to 12 hours to completely saturated.

How to soak bricks?

In a multi-storey building it is not possible to soak bricks in one floor and carry to others floor. So we make separate water tank for each floor.

Making temporary soaking tank -

  • Use a plastic drum initially for soaking bricks till the soaking tank is ready.

  • Soak bricks in plastic drum for 12 hours and take out the bricks from drum one hour before starting brick masonry work.

  • With these soaked bricks make wall layout on floor as shown in architectural drawing. Make necessary changes as per client/owner's decision and finalize the layout.

  • The size of water tank depends on how many masons will work for a day or how many bricks will be needed for a day. Depending on the size of water tank choose a room or toilet to make soaking tank.

  • Make a wall around your chosen room up to 2½ feet or 3 feet high. Don't forget to keep door opening for the room during making masonry wall.

  • After making room's wall, make a wall for door opening of same height. But don't make the masonry bond between wall of door opening and the rest of wall. So that you can break the door opening's wall later.

  • Next day make plaster with net cement finishing on inner wall surface of soaking tank. The purpose of net cement finishing is to make the water tank leakage proof.

  • During making wall around water tank put a 2" diameter pvc pipe at bottom of wall. Dirty water after soaking brick will be discharged through this pipe.

  • Put the required quantity of bricks for day's work into water tank previous day and take out from water tank one hour before starting brick work to sweep out the excess water from bricks.


YOUR TURN:
How do you soak bricks? Please share in comments...

 
Read More
// // 3 comments

Essential Team Members for Construction Project Management

In a construction project, small or big, there are many issues involved during the lifetime of project. Such as -
  • Contractor/Sub-contractor issue
  • Quality issue
  • Costing issue
  • Material issue, and
  • Safety and security issue, etc.

To handle and organise all these issues we need a strong and balanced management team in a construction project. This team should have following members.

construction project management, team members of construction project management

Essential team members for construction project management -
  • Project Manager,
  • Project Engineer,
  • Site Engineer/Supervisor,
  • Store Officer, and
  • Security Guards.

Project Manager: He is the leader of the team. He arranges and employs contractors/sub-contractors and prepare work-orders. Project manager is also responsible to train-up and motivate his team members, Mitigate any internal, governmental and local disputes which can hamper the progress of project.

Read More: 7 Responsibilities of a Construction Project Manager

Project Engineer: A project manager not only controls one project he also controls several other projects. But a project engineer controls only one project. He resolves internal issues, motivate and train-up team members and follow up them and reports project manager time to time and operate the project as directed by project manager.

Site Engineer/Supervisor: Site engineer or supervisor guides contractors/sub-contractors, supervise the works, makes requisitions for required materials to smoothly operate the construction works and controls the quality of works. Site engineer also ensures the safety of project.

Read More:
Responsibilities of Construction Supervisor.

10 Must Follow Safety Tips for a Construction Project.

Store Officer: Store keeper controls store. He receives materials, maintains stock-registers and reports about materials stock to project engineer time to time. It is store officer's responsibility to deliver the required materials to the project on due time. In some construction companies he also handles the purchase related tasks.

Security Guard: Most important person of a construction project. Security guard should be honest and sincere. Because, when no one is in the project, it is guards responsiblity to protect the project from any unwanted activities.

Actually, security guard is not judged as management team member. I included them in project management team because most of the time they works as a helping hand of project management team.

If the project is very big then several other members are included in project management team. Such as, Deputy Project Engineer, Quality Engineer, Safety Engineer etc.


YOUR TURN:
Do you have a member in your project management team which I've not included here? Please share in comments...
Read More