👉Concrete admixtures

💫Concrete admixtures are additives, either chemical or mineral, added to concrete during mixing to modify its properties, improving workability, durability, strength, and other characteristics. 

🏷Here's a more detailed explanation of concrete admixtures:

❇️What are Concrete Admixtures?

⏺Admixtures are substances other than water, aggregates, cement, and fibers used to modify the properties of concrete, both in its fresh (unhardened) and hardened (set) states. 
⏺They can be either chemical or mineral. 
⏺They are added to the concrete mix before or during mixing. 

📜Types of Concrete Admixtures:
Chemical Admixtures:

🎲Water-reducing admixtures: 

⏺Reduce the amount of water needed for a given concrete mix, improving workability and strength. 

🎲Superplasticizers: 

⏺Enhance workability and flowability of concrete, allowing for high-strength concrete without sacrificing workability. 

🎲Accelerators: 

⏺Speed up the setting and hardening of concrete, leading to faster strength gain. 

🎲Retarders: 

⏺Slow down the setting time of concrete, allowing for easier handling and placement, especially in hot weather. 

🎲Air-entraining agents: 

⏺Introduce small, controlled air bubbles into the concrete mix, improving its resistance to freeze-thaw damage. 

🎲Corrosion inhibitors: 

⏺Protect reinforcing steel from corrosion, extending the lifespan of concrete structures. 

🎲Shrinkage reducing admixtures: 

⏺Minimize drying shrinkage cracking in concrete. 

🎲Mineral Admixtures:
Silica fume: 

⏺A fine, pozzolanic material that improves durability, strength, and reduces permeability. 

🎲Fly ash: 

⏺A byproduct of coal combustion that can act as a pozzolan, improving concrete properties. 

🎲Ground granulated blast-furnace slag: 

⏺A pozzolanic material that can improve concrete durability and strength. 

⭐️Benefits of Using Admixtures:

🔰Improved Workability:

⏺Admixtures can make concrete easier to place, finish, and pump. 

🔰Enhanced Durability:

⏺Admixtures can improve concrete's resistance to freeze-thaw damage, chemical attack, and abrasion. 

🔰Increased Strength:

⏺Admixtures can help achieve higher concrete strengths, both early and at later ages. 

🔰Reduced Water Content:

⏺Water-reducing admixtures allow for a reduction in the water-cement ratio, leading to stronger and more durable concrete. 

🔰Cost-effectiveness:

⏺Admixtures can help optimize concrete mixes, potentially reducing overall project costs. 

@etconp

👉Avoid construction disputes

⏺Prevent conflicts before they start! Clear contracts, proper planning, and transparent communication are the keys to a smooth construction project.

⭐️How to Avoid
Construction Disputes.

📌Clear Contract

🔗Write down scope, timelines, and payments.

📌Document Everything

🔗Keep records of drawings, approvals, and materials.

📌Good Communication

🔗Talk regularly and share updates in writing.

📌Plan Properly

🔗Schedule work realistically and identify risks.

📌Manage Changes

🔗Record all changes with approvals and costs.

📌Check Quality

🔗Inspect work regularly and fix problems early.

📌Timely Payments

🔗Follow agreed payment schedule.

📌Follow Laws & Codes

🔗Ensure work meets legal requirements.

📌Resolve lssues Early

🔗Address small problems before they grow.

@etconp

👉ለኢተዮጵያ አርክቴክቶች ማህበር የስራ አስፈጻሚ ቦታዎች እራስዎንም ሆነ ሌሎችን ይጠቁሙ።

📜ዝርዝሩን ከታች በተያያዘው የማህበሩ ኦፊሴላዊ መግለጫ  ይመልከቱ።

🚧AEA Members, it's an Election Year! 🗳

⏺Nominations are now open for the upcoming Executive Committee positions as part of the 25th Convention & Annual General Assembly.

✔️ Self-nomination encouraged
✔️ Submit one nomination at a time
✔️ Nominate multiple people by reopening the link
✔️ Add contact details of nominees for follow-up

❇️Have someone in mind who would make a great EC member? Or ready to take the lead yourself?

🔗 Submit your nomination here:👇 https://forms.gle/AQXKSfGgAqvnqceC6

⭐️Let’s shape the future of our association together.

#AEA #ElectionYear #ArchitectsEthiopia #AGA25

@etconp

👉 INTERCON Construction Chemicals 

● Concrete Admixtures
● Bonding Agents
● Waterproofings
● Wall Putty, Prime Coat
● Concrete Repair Mortar
● Floor hardener, Epoxy
● Grout, Self-level mortar
● Quartz paint, Contextra
● Tile Adhesive & Tile Joint Fillers 
● Geotextiles and other construction chemicals and materials

☎️ Tel: 0961955555

🔹 Address 1: Signal road, around
      Dinberwa Hospital

🔹 Addres 2: Wellosefer, Infront of
     Dani Plaza

👉FORMWORK DISMANTLING:

💫Formwork dismantling, also known as stripping or striking, involves carefully removing the temporary molds used to shape concrete after it has hardened, ensuring the concrete structure is not damaged and that the formwork is handled safely. 

🏷Here's a more detailed breakdown of the process:

🚧1. Timing is Crucial:

Wait for Concrete to Cure: 
Formwork should only be removed after the concrete has gained sufficient strength to support itself.

📍Factors Affecting Curing Time: 

The exact time depends on the concrete mix, ambient temperature, humidity, and the structure's load-bearing requirements. 

Don't Rush: 
Removing formwork prematurely can lead to structural failure or damage. 

🚧2. Safe Dismantling Practices:

Systematic Approach: 
Develop a systematic method for releasing and lowering components in a controlled manner. 

Start from the Top: 
Remove the highest forms first, working downwards. 

Use Appropriate Tools: 
Use pry bars, hammers, or lifting equipment, as appropriate, to avoid damaging the concrete surface. 

Avoid Damage: 
Be careful not to damage the concrete, especially edges and corners. 

Maintain Structural Balance: 
Remove formwork on alternating sides to help maintain structural balance. 

Safety First: 
Use temporary platforms to minimize the risk of falls when stripping and ensure adequate lighting. 

Protect Workers: 
Protect workers from falling objects by setting up exclusion zones and installing warning signs. 

Curing After Removal: 
After removing the formwork, cover all exposed surfaces with polythene or wet hessian or ጆንያ to prevent moisture loss for about 5 days, so that the concrete is fully cured. 

🚧3. Specific Considerations:

Vertical Formwork:
Often removed by using pry bars, hammers, or lifting equipment, as appropriate. 

Horizontal Formwork:
May require props to be left under the slab until it gains sufficient strength. 

Bridge Formwork:
Follow specific procedures for dismantling steel formwork of bridges, including removing supports and arches in a controlled manner. 

Aluminum Formwork:
Follow specific procedures for construction and dismantling of aluminum alloy formwork, including removing diagonal supports and wall bolts. 

🚧4. Post-Dismantling:

Recycle or Dispose Responsibly:
If formwork is still in good condition, it may be reused for other parts of your project or stored for future projects. 

Clean and Store:
Clean up the removed formwork and accessories in time, and transport them to the same position on the upper floor and lay them flat. 

Maintenance:
Ensure the formwork is carefully handled at all times to maintain its value and operational readiness. 

Waste Removal:
Damaged material Boards shall be removed as per Ethiopian waste management procedures. 

@etconp

👉Factors influencing the strength of concrete

💫The strength of concrete is mainly affected by the quality of raw materials, cement content, water-to-cement ratio, concrete pressure during pouring, concrete life, and treatment conditions.

Any failure in these factors will result in weak mechanical resistance of concrete.

⭐️Major factors affecting the strength of concrete፦

1. Quality of Raw Materials

Cement: It must meet standard specifications and be stored in dry conditions. Any pollution or loss of quality diminishes strength.

Gravel (gravel and sand): Its shape, size, purity, clay and salts (chlorides, sulfates) are very important.

Water: Preferably drinkable, as contaminated water affects chemical reaction.

2. Water to Cement Ratio

As the percentage of water to cement increases, the gaps in the interior structure of concrete increase, thus the strength decreases.
The ideal ratio strikes a balance between maneuverability and pressure force.

If the percentage is too low, the concrete becomes hard of the blood, which also leads to weak strength

3. The Contents of  Cement

Increasing cement content (with consistency of water) reduces the content of water to cement, thus increases strength.

But too much cement can lead to shrinking and cracking problems.

4. Compaction of Concrete

Good blood removes air gaps and increases the density of concrete, improving its resistance.
Weakness of pressure leads to internal gaps that diminish strength.

5. The Age Of Concrete

Concrete gains most of its strength within 28 days of pouring.

Strength continues to increase with age if handled correctly

6. The Conditions of Curing

Curing Compounds are essential to retain moisture.

Untreated direct sun exposed concrete is much weaker than treated concrete.

📜Practical notes

⏺Untreated concrete under direct sun may be as strong as one quarter of the strength of water-treated concrete at 20°C.

❇️Therefore, processing and durability are the two most neglected workers on site, though they determine the quality of final concrete more than anything else.

@etconp

👉Main abbreviation in Construction engineering

1. BBS= Bar Bending Schedule

2. F.O.S= Factor of Safety

3. RCC = Reinforced Cement Concrete

4. PCC = plain cement concrete

5. NDT = Non destructive test

6. DL = Dead load

7. LL = live load

8. UDL = uniformly distributed load

9. FEM = finite element method

10. CAD = computer aided design

🙋 Question 💬

1️⃣. What’s EBCS

2️⃣. what’s BIM stands for

3️⃣. what’s FCR

4️⃣. What’s W/C ratio

5️⃣. What’s FM ?

6️⃣. What’s TMT ?

7️⃣. What’s Fck

8️⃣. What’s HYSD

@etconp