Ethiopian Construction Work Professionals - ETCONp

Pollu ላይ vote እያረጋችሁ ብዙ ድምፅ ያገኘው ቅድሚያ ይሰጠዋል

👉What is Super Elevation in a Road?

💫Super elevation; is the banking of a road curve, designed to counteract the centrifugal force that vehicles experience when navigating a turn. By tilting the road surface, super elevation helps vehicles maintain traction and stability, reducing the risk of skidding or overturning.

⭐️Purpose of Super Elevation;

The primary purpose of super elevation is to provide a safe and comfortable driving experience, especially at high speeds. By reducing the centrifugal force, super elevation helps to:

- Improve vehicle stability
- Reduce the risk of skidding or overturning
- Enhance driver comfort and safety
- Increase the overall safety of the road

⭐️Design Considerations for Super Elevation;

When designing super elevation, engineers consider several factors, including:

- Design speed: the speed at which vehicles are expected to travel
- Curve radius: the sharpness of the turn
- Road surface: the type of pavement and its frictional characteristics
- Vehicle characteristics: the type of vehicles using the road and their dynamic properties

⭐️Types of Super Elevation;

There are two main types of super elevation:

- Linear super elevation: a constant rate of banking along the curve
- Parabolic super elevation: a varying rate of banking along the curve, with the maximum banking at the midpoint

⭐️Importance of Super Elevation;

Super elevation is a critical component of road design, as it directly affects the safety and comfort of drivers. Well-designed super elevation can:

- Reduce the risk of accidents
- Improve traffic flow
- Enhance driver comfort and safety
- Increase the overall safety of the road

📜Conclusion;

In conclusion, super elevation is a vital element in road design, requiring careful consideration of factors such as design speed, curve radius, and road surface. By providing a safe and comfortable driving experience, super elevation plays a critical role in reducing the risk of accidents and improving traffic flow.

@etconp

👉በአለማችን ትልቁ ሰው ሰራሽ ደሴት ላይ ቻይና እያስገነባች የምትገኝው አውሮፕላን ማረፍያ

በአሁኑ ወቅት በቻይና 200 አውሮፕላን ማረፊያዎች ኣላት

ቻይና አዳዲስ ፈጠራዎችን በማስተዋወቅ እና ግዙፍ ፕሮጀክቶችን በመግንባት በአለም ቀዳሚ የምትሆንበትን አዲስ ፕሮጀክት እየገነባች ትገኛለች፡፡

ሀገሪቱ በአለማችን ግዙፍ በተባለው ሰው ሰራሽ ደሴት ላይ በግዝፈቱ ተወዳዳሪ አይኖረውም የተባለውን ኤርፖርት እውን ለማድረግ እንቅስቃሴ ጀምራለች፡፡

አራት ትላቅ የአውሮፕላን መንደርደርያዎችን እና ማረፊያዎችን ይይዛል የተባለው የደሴት ላይ ኤርፖርት 900 ሺ ስኩየር መሬት ላይ ያረፈ የመንገደኞች ማስተናገጃ (ተርሚናል) ይይዛል፡፡

በሂደት 20 ስኩየር ኪሎሜተር ስፋት ለመሸፈን ያቀደው የደሴት ኤርፖርት የሆንግኮንግ አለም አቀፍ ኤርፖርት እና የጃፓኑን ካንሳይ ኤርፖርት በመብለጥ ቀዳሚ ይሆናል፡፡

በተጨማሪም በአመት 80 ሚሊየን መንገደኞችን እና 540 ሺ በረራዎችን የሚያስተናግድ አቅም ይኖረዋልም ተብሏል፡፡  

7.5 ሚሊየን ሰዎች በሚኖሩበት ዳሊያን በተሰኝ ከተማ ላይ የሚገነባው አውሮፕላን ማረፊያ ለጃፓን እና ደቡብ ኮርያ ካለው ቅርበት አንጻር ከፍተኛ የትራንስፖርት መነሀሪያ እንደሚሆን ይጠበቃል፡፡

በከተማዋ ለ100 አመታት ያገለገለው የዳሊያን ጆሽዊዢ ኤርፖርት ለበርካታ ጊዜ ማስፋፋፍያ ቢደረግለትም አሁን ላይ ያሉትን ደንበኞች ወይም ተጓዦች ማስተናገድ የሚችልበት አቅም ላይ እንደማይገኝ ሲኤንኤን አስነብቧል፡፡

የፕሮጀክቱ ዋና መሀንዲስ ሊ ያንግ ግንባታው በውሀ ላይ እንደመገንባቱ እንዲሁም ከሚሸፍነው ቦታ ስፋት አንጻር ውስብስብ የኮንስትራክሽን ቅየሳዎችን ቢፈለግም መሳካቱ እንደማይቀር ተናግረዋል፡፡

ኤርፖርቱን ለመገንባት በ2003 የቦታ መረጣ እና የማሳያ ስራ የተጀመረ ቢሆንም ግንባታው የተጀመረው ከጥቂት አመታት በፊት ነው አዳዲስ አውሮፕላን ማረፊያዎች የቻይና የአቪዬሽን እድገት ማሳያ ቁልፍ አካል ናቸው።

ሀገሪቱ አሜሪካን በመብለጥ የዓለማችን ትልቁ የአየር መጓጓዣ ገበያ ማዕከል ለመሆን በመንገድ ላይ ነች።

ዳክሲንግ የተባለው የቤጂንግ ሁለተኛ ግዙፍ አውሮፕላን በ2019 ለአገልግሎት ክፍት ሲሆን የቻይና ባለስልጣናት ሀገሪቱ የአየር ትራንስፖርት ፍላጎትን ለማሟላት በ2035 450 አየር ማረፊያዎች እንደሚያስፈልጓት ተናግረዋል።

@etconp

👉This type of test is conducted to accurately identify the location of buried pipes or cables to avoid damage during excavation or construction projects.

💫1. Purpose of the Test:

To identify the locations of buried utilities such as electrical cables, pipelines, or drainage systems.

To minimize the risk of damage during excavation or construction.

To ensure the safety of the site and workers.

💫2. Device Used:

The device in the image is a detection tool that likely operates using technologies such as electromagnetic frequencies or radio signals.

A signal is transmitted through the cable or pipe, and the device receives the signal to pinpoint its exact location.

💫3. Procedures:

Identify the area to be inspected based on maps or engineering plans.

Operate the device and adjust the settings as needed to detect the type of material (e.g., metal or plastic).

Move the device over the target area to accurately locate the utilities.

💫4. Results:

Coordinates (as shown in the image) are recorded to ensure accurate documentation of the location.

The results are used to adjust excavation or construction plans to avoid damaging cables or pipes.

💫5. Importance:

Protects buried utilities and infrastructure.

Reduces repair costs caused by damages.

Ensures the safety of the team and equipment.

Via Yonatan Tadesse PMP

@etconp

👉Calculating Maximum Dry Density (MDD) and Optimum Moisture Content (OMC) of Coarse Aggregate for Base Course On Road Construction

💫Understanding MDD and OMC

🏷Before we delve into the steps, let's clarify what MDD and OMC signify:

* Maximum Dry Density (MDD): This is the highest density a soil can achieve in a controlled laboratory environment under specific compaction efforts.
* Optimum Moisture Content (OMC): This is the moisture content at which a soil reaches its maximum dry density under those same compaction efforts.
Why are MDD and OMC important?
* Achieving Adequate Compaction: By knowing the MDD and OMC, engineers can ensure that the soil used in the base course of a road is compacted to its maximum potential, leading to a more durable and stable road structure.
* Preventing Over-Saturation: Compacting soil that is too wet can lead to excessive water content, which can weaken the soil and reduce its load-bearing capacity.
* Ensuring Proper Drainage: If the soil is too dry, it can be difficult to compact properly, and it may not be able to effectively drain water, which can lead to frost heave and other problems.
Steps to Determine MDD and OMC
The standard method for determining MDD and OMC is the Proctor Compaction Test. Here's a simplified overview of the process:
* Sample Preparation: A representative soil sample is collected and prepared according to standard laboratory procedures.

* Moisture Content Determination: A portion of the soil sample is oven-dried to determine its natural moisture content.
* Compaction: The remaining soil sample is divided into several portions, each with a different moisture content. Each portion is placed in a cylindrical mold and compacted using a standardized hammer and number of blows.
* Bulk Density Calculation: The weight and volume of each compacted soil sample are measured to calculate its bulk density.
* Dry Density Calculation: The bulk density is then converted to dry density by accounting for the moisture content.
* Plotting the Compaction Curve: The dry density values are plotted against their corresponding moisture contents to create a compaction curve.
* Determining MDD and OMC: The peak of the compaction curve represents the maximum dry density (MDD), and the corresponding moisture content at this peak is the optimum moisture content (OMC).
Visual Representation:
Key Considerations for Coarse Aggregates:
* Modified Proctor Test: For coarse-grained materials like those used in base courses, the Modified Proctor test is typically used, which involves a heavier hammer and more blows than the Standard Proctor test.
* Field Compaction: The MDD and OMC values obtained from the laboratory test serve as targets for field compaction. Field density tests are performed to ensure that the actual compaction achieved in the field meets the specified requirements.

⏺By following these steps and understanding the significance of MDD and OMC, engineers can ensure that the base course of a road is constructed with the optimal moisture content and maximum density, leading to a more durable and long-lasting pavement structure.

@etconp

👉What is the Difference Between Beam and Lintel ?

🏷Beams and lintels are both horizontal structural members used in construction, but they serve distinct purposes and have some key differences:

💫Beams

⏺Function

* Primarily used to support vertical loads over long spans.
* Transfer loads from floors and roofs to columns and walls.

⏺Location:

* Typically run parallel to the length of the building.
* Can be found in various locations within the structure, including floors, roofs, and basements.

⏺Span:

* Generally have longer spans compared to lintels.

💫Lintels


⏺Function:

* Specifically used to support the weight of masonry (bricks, stone, etc.) above openings like doors and windows.
* Transfer the load to the sidewalls of the opening.

⏺Location:

* Positioned horizontally above openings in walls.

⏺Span:

* Have shorter spans, typically spanning the width of an opening.

❇️In essence:

* All lintels are beams, but not all beams are lintels.
* Lintels are a specific type of beam with a specialized function and location within a structure.

@etconp

👉Pipe Frame Scaffolding

🏷This type of scaffolding is most commonly found on construction sites and is used to support workers and materials on various jobs.
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⭐️Main components of scaffolding:

1. Top Rail
Provides protection to prevent workers from falling down.

2. Mid Rail
Added as an extra safety measure next to the top handrail.

3. Toe Board
Prevents tools or materials from falling off the work platform.

4. Board
It is the work surface on which workers stand.

5. Post/Standard (Vertical Column):
The main post that carries the entire chassis.

6. Random Orthodontic Brackets (Random Orthodontic Brackets):
Enhances horizontal and vertical stability for the scaffold.

7. Holders/Transoms (Horizontal Defects):
Support panels and tie vertical columns together.

8. Couplers (Connectors):
Used to tie scaffolding pieces together strongly and safely.

9. Base Plate (Metal Base):
Vertical posts are placed to distribute lambs on the ground.

10. Sill/Sole Board (Wooden Base):
Used to reduce soil pressure and provide more stability.

11. Runners/Ledgers  (Longitudinal Impact):
Attach long vertical columns for better stability

12. Self-closing strips):
Used to secure entrances and exits

13. Longitudinal ties
Stability is reinforced by scaffolding

14. Base lift/player lift (lower bracket): It provides extra support for the chassis below

@etconp

👉🔸ተለዋዋጭ ኮምፓክት/Dynamic compaction

⭐️በጂኦቴክኒክ ምህንድስና ጥቅም ላይ የሚውል የመሬት ማሻሻያ ቴክኒክ ሲሆን ደካማ አፈርን ለማጥለቅ የሚያገለግል ነው።

🏷ይህም ከትልቅ ከፍታ ላይ በተደጋጋሚ ከባድ ክብደት ወደ መሬት ወለል ላይ መጣል ሲሆን፣ ተለዋዋጭ ተጽእኖ የሚመነጨው የማይንቀሳቀስ ክብደት (ከ15-40 ቶን) ከተወሰነ ቁመት (10-30 ሜትር) ድረስ በመጣል ነው

💫እነዚህ ጥብቅ ምቶች በአፈር ላይ ንዝረትን ይፈጥራሉ ፣ ይህ ንዝረትም የአፈሩ አቅምን ያሻሽሽላል፣ የንዝረት ተፅዕኖውም እስከ 12 ሜትር ጥልቀት ይደርሳል።

⏺ይህም ክብደት ለተወሰኑ ጊዚያት በቦታው/ሳይቱ ላይ ባለው የፍርግርግ/Grid pattern ላይ ለተወሰኑ ጊዜያት ይጣላል

⏹ሂደቱ የሚፈጥራቸው እያንዳንዱ ነጠብጣብ ቦታ ላይ የተፈጠሩት አሻራዎች ከእያንዳንዱ ማለፊያ በኋላ በጠጠራማ ሰለክት ማቴሪያል ይሞላሉ።

🎲ጥቅሞች፡-

⏺1. የተለያዩ ደካማ የአፈር አይነቶችን የማሻሻል አቅም ያለው መሆኑ

⏺2. የመሸከም አቅም መጨመር

⏺3. የቀነሰ ሴትልመንት

⏺4. የታከሙ ሰለክት አፈር እና ሙላዎች መጠጋጋት፣ የግጭት አንግል እና ግትርነት ይጨምራሉ

⏺5. ጥልቀት የሌላቸው መሠረቶች ያለ

📍ጥልቅ ቁፋሮ ወይም መቆለል እስከሚችሉ ድረስ በዳርቻ ቦታዎች ላይ ያለውን የአፈር ሁኔታ ማሻሻል ይችላል።

@etconp

👉The Ethiopian Roads Authority (ERA) has specific standards for compaction degrees in road construction, ensuring optimal performance and durability. These standards typically vary depending on the layer type and material properties.

💫General Guidelines:

* Subgrade: 95-98% of the maximum dry density (MDD) as determined by Standard Proctor or Modified Proctor test.
* Subbase: 95-98% of the MDD, similar to the subgrade.
* Base Course: 98-100% of the MDD, requiring higher compaction for load-bearing capacity.
* Capping Layer: 95-98% of the MDD, depending on the material used and its function within the pavement structure.

💫Factors Influencing Compaction Degree:

* Material Type: Different materials have varying compaction characteristics.
* Layer Thickness: Thicker layers may require more effort to achieve desired compaction.
* Moisture Content: Proper moisture content is crucial for optimal compaction.
* Equipment Type: The type of compaction equipment used can influence the achievable density.
* Traffic Load: Higher traffic loads may necessitate higher compaction degrees in lower layers.
Importance of Compaction:
* Stability: Adequate compaction provides stability and resistance to deformation under traffic loads.
* Durability: Well-compacted layers contribute to the overall durability of the pavement structure.
* Drainage: Proper compaction can improve drainage characteristics, reducing the risk of water damage.
* Uniformity: Consistent compaction ensures uniform support for the overlying layers.

⭐️ERA Standards:

For precise and up-to-date compaction requirements, it's essential to refer to the specific ERA standards and specifications applicable to the project.

These documents will provide detailed guidelines based on the latest research and industry best practices.

By adhering to these standards, road construction projects in Ethiopia can achieve high-quality pavements that are safe, durable, and resilient to the challenges of the local environment and traffic loads.

@etconp

👉Concrete roads are a very expensive choice in the desert for several main reasons:

💫1. The cost of the raw materials :

Concrete needs high-quality materials, such as cement that is resistant to salt, sand, and lime, which increases cost compared to asphalt roads.

💫2. A special design to withstand desert conditions:

To ensure concrete resists cracking and corrosion due to heat and sand, expensive components such as fibers and chemical additives are added, as well as designing more complex extension spacers.

💫3. Transport costs:

Desert project sites are often far from material sources, resulting in a significant increase in transportation costs.

💫4. THE NEED FOR A STRONG FOUNDATION :

Sand soil in the desert requires a strong and stable foundation, which adds an extra cost to the preparatory work.

💫5. Long term maintenance:

Although concrete roads last longer, the cost of maintaining them in a harsh desert environment is high due to the need to periodically address erosion and cracking.

💫6. The cheaper alternatives:

Asphalt driveways are considered significantly less costly to build and maintain, making them the most common choice in desert areas, unless the need requires long-term infrastructure.

⭐️High cost makes concrete roads a less attractive option in desert projects, unless the goal is to invest in an infrastructure that lasts for decades without the need for major changes.

@etconp