የህንፃ ኤሌክትሪክ መስመር ዝርጋታ


1 .መግቢያ/Introduction
2. ጥንቃቄ/Safety
3.መሰረታዊ የኤሌክትሪክ ፅንሰ ሀሳቦች/Basic Electrical Cnecepts
4.የኤሌክትሪካል ምልክቶች/Electrical Symbols
5.የእጅ መሳሪያዎች/Hand tools
6.የኢትዮጵያ የህንፃ ኮድ መመሪያ/EBCS
🔜የኤሌክትሪክ ገመድ ቀለም ደንብ/Electrical Wire color code
🔜የኤሌክትሪክ ገመድ መጠን/Electrical Wire Size
🔜የኤሌክትሪክ አክሰሰሪዎች ከመሬት ያላቸው ከፍታ/Electrical Accessories Height from floor
7.ኮንዲዩትና የኮንዲዩት አክሰሰሪዎች/Conduit & Conduit Accessories
🔜ኮንዲዩት/Conduit
🔜የኮንዲዩት አክሰሰሪዎች/Conduit Accessories
▪️ማጋጠሚያ/Coupler
▪️ስካቶላ/Junction(conduit)box
▪️ቤንድ፣ኤልቦው፣ቲ/Bend,Elbow,Tee
8.የኤሌክትሪክ ገመድ ዝርጋታና አሰራር /Electrical Installation & Wiring syetems
🔜የኤሌክትሪክ ገመድ አይነቶች/ Electrical Conductor types
🔜የኤሌክትሪክ ሽቦ ጫፍ አዘገጃጀት/Electrical wiring termination
🔜የኤሌክትሪክ ሽቦ አስተሳሰር ዘዴዎች/ Methods of Electrical wire splicing
🔜ሌይአዉትእና ወየሪንግ ስዕል/Layout and Wiring Diagram
9. ድሮዊንግ ማንበብና መረዳት (መተርጎም)/Read & Interprate working Drawings
10.መዳብ መቅበርና መከላከያ መሳሪያዎች አጠቃቀም/Earthing & Protective Devices
11. ሌሎች/Others
12. ከሰዎች ጋር አብሮ የመሰራት እና የደንበኛ አያያዝ ጥበብ/ Arts of Working with others & Customer handling

ይቀጥላል .......

https://t.me/engineer03

1.ኮንዲዩት/ፓይፕ ማጠፊያ (Conduit/Pipe Bender)

☑️በእሳትና በአሸዋ ወይም በእሳት ብቻ በመጠቀም (አብዛኞቻችን የምንጠቀምበት) ማጠፍ እንችላለን። ነግር ግን ጊዜ የሚያባክንና እጃችንም የሚጎዳ ስለሆን መሳሪያ መጠቀሙ አስፈላጊ ነው።
☑️ኮንዲዩት/ፓይፕ ማጠፊያ (Conduit/Pipe Bender) የተለያዩ አይነት ማጠፊያዎች/Benders ሲኖሩ ከነዚህም ዋና ዋና የሚባሉት የሚከተሉት ናቸው።
1.በእጅ የሚሰራ ማጠፊያ (Hand/manual bender)
2. ሀይድሮሊክ(Hadraulic)
3.ኤሌክትሪክ(Electric)
4.ሜካኒካል(Mechanical) ሲሆኑ በቀላሉ ከቦታ ቦታ ለማንቀሳቀስ አመች የሆነው እና ለሳይት ስራ የሚሆነው በእጅ የሚሰራ ማጠፊያ (Hand/manual bender) ነው። ስለዚህ በዚህ ክፍል የምናየው ይሄን ይሆናል።
🔹በእጅ የሚሰራ ማጠፊያ (Hand/manual bender)
☑️መጠናቸው(sizes) አነስተኛ ለሆኑ ኮንዲዩቶች እና የኤሌክትሪክ ሀይል የሌለበት ቦታ ላይ በጣም ጠቃሚ ነው።
☑️መጠናቸው ከፍተኛ ለሆኑ ፓይፕ/ኮንዲዩት በተለይ ለቧንቧ ስራ ከላይ ከተዘረዘሩት ውስጥ እንደ አስፈላጊነቱ መርጦ መጠቀም ተገቢ ነው። ምክንያቱም ማጠፍ በፈለግን ጊዜ መሳሪያውን የምናቀሳቅሰው በእግራችን ወይም በእጃችን ስለሆን ከፍተኛ ሀይል/ጉልበት ስለሚጠይቅና አቅማቸውም ውስን ስለሆነ ነው ለትላልቆችና ብዛት የምናመርት ከሆነ ከላይ ከተዘረዘሩት ውስጥ መርጠን መግዛት አለብን።

https://t.me/engineer03

የቀጠለ...

☑️ መሳሪያውን ተጠቅመን ኮንዲዩት ለማጠፍ ልምምድ ማድረግ አስፈላጊ ነው በአንዴ በፈለግነው መልኩ ካላጠፍን ብለን መጨነቅ አይኖርብንም።
☑️አሪፍ ቤንድ ለመስራት ደረቻውን የጠበቀና ሪጅድ ኮንዲዩት መጠቀምም አስፈላጊ ነው።
☑️የእጅ ማጠፊያዎች በብራንዳቸውና በሞዴላቸው መሰረት ይልያያሉ። ነገር ግን በብዛት የሚታወቁት ሁለት ናቸው። እነርሱም:-
🔹ቤንፊልድ ማጠፊያ(Benfield Bender):-
☑️ከብረት የተሰራ ሲሆን ላዩ ላይ በፈለግነው የአንግል መጠን ኮንዲየቱን ለማጠፍ የሚረዱን ጠቋሚ ቁጥሮች አሉ።
🔸ጋርድነር ስልት መጠፊያ(Gardner Style Bender):-
☑️ከአሉሚንየም የተሰራ ሲሆን 45 ዲግሪና 90 ዲግሪ ላይ የምናስተካክልበት ደረጃ አለው።

https://t.me/engineer03

የቀጠለ...

🔹በበዛት የተለመደውና አብዛኛቻችን የምንስማማበት የኤሌክትሪክ አክሰሰሪዎች ከወለል ያላቸው ከፍታ:-

የክሰሰሪ ከወለል ያላቸው
አይነቶች ከፍታ በ cm
1. ማብሪያ/ማጥፊያ_____130-140
2.ሶኬት_________________40-50
3.ዲስትሪቢዩሽን ቦርድ___170-175
4.ኪችን ሶኬት___________90-100
5.አኑንሴተር_____________170-175
6.ቤል ስዊች_____________130-140
7. ቆጣሪ_________________175-180
8.ሻወር/መፀዳጃ ቤት
ሶኬት____________________180-200
9. ሻወር/መፀዳጃ ቤት ማብሪያ ማጥፊያ__________________150

ማሳሰቢያ:- ከዚህ በፊትም እንዳልነው ዋናው ነገር ለአጠቃቀም ቀላልና ምቹ ማድረግ ነው። ስለዚህ ቦታው ላይ ያሉትን ነገሮች ታሳቢ በማድረግ እንደሁኔታው ከፍም ዝቅም ማለት ይችላል።

ይቀጥላል ......

ዒድ ሙባረክ!
عيد مبارك

እንኳን ለ1,441ኛው የኢድ አል-ፈጥር በዓል በሰላም አደረሰን ፤ አደረሳችሁ። በዓሉ የሰላም ፣ የፍቅር ፣ የመተሳሰብ ይሆን ዘንድ እንመኛለን!

ውድ ቤተሰቦቻችን በዓሉን ስናከብር የኮቪድ-19 ወረርሽኝን ለመከላከል የምንወስዳቸውን አስፈላጊ #የጥንቃቄ እርምጃዎችን እየወሰድን እንዲሆን አደራ ለማለት እንወዳለን!


عيد مبارك
መልካም በዓል ይሁንልን!

Civil Engineer’s Work

https://t.me/engineer03

1,ኮንዲዩት/Conduit:-

🔸ኮንዲዩት ወይም በአማረኛ ቱቦ ብለን የምንጠራው ሲሆን ለኤሌክትሪክ ወይም ለውሃ አገልግሎት የምንጠቀምባቸው የተለያዩ አይነቶች አሉ። እኛ የምናየው ለኤሌክትሪክ አገልግሎት የምንጠቀምባቸውን አይነቶች ነው።
🔸ኮንዲዩቶች ኤሌክትሪክ ለማስተላለፍ የምንጠቀምባቸውን ገመዶች ወይም ኬብሎች በወስጣቸው አሳልፈን በመዘርጋት ከሜካኒካል ወይም ከኤሌክትሪካል ጉዳት ለመከላከል ይረዱናል።
🔹 በውፍረትና በአይነት የተለያዩ ኮንዲዩቶች ስላሉ እንደ አስፈላጊነታቸው እንጠቀምባቸዋለን።
🔸ኮንዲዩቶች ባዋናነት በሁለት የከፈላሉ። እነርሱም:-
1.የብረት ኮንዲዩት/ steel/Metal coduit
2. የፕላስቲክ/plastic conduit
ናቸው።

🗝እያንዳንዱን እናያለን!
👇👇👇👇👇 https://t.me/engineer03

🔹🔸🔹1. የብረት ኮንዲዩት/ steel coduit:-
🔹የኤሌክትሪካል ገመዱን/ኬብሉን ከሜካኒካል ጉዳት መከላከል አስፈላጊ ሆኖ ስናገኘው እንጠቀመዋለን።
🔹በሶስት ዋና ዋና ክፍሎች ይከፈላል።
ሀ. ደረቅ የብረት ኮንዲዩት(Rigid Steel Conduit)
ለ. ታጣፊ የብረት ኮንዲዩት(Flexible Steel Conduit)
መ. የብረት ሆዝ(Metallic Hose) ናቸው።👇👇👇👇👇👇👇👇👇👇 https://t.me/engineer03

🔹🔸🔹ሀ. ደረቅ የብረት ኮንዲዩት(Rigid Steel Conduit):-
🔸ለአጣቃቀም እንዲመች ሲባል እርዝመቱ 3 ሜትር ነው።
🔸🔹ጫፉ ላይ ጥርስ የመሰለ ነገር ያለው ሊሆን ይችላል/እኛ እራሳችን ጥርስ ልናወጣለትም እንችላለን። ጥርሱም የተለያዩ የብረት ኮንዲዩቶችን ለማጋጠም/ለማገናኘት ይረዳናል ~ከቤት ውጭ ለሆነ ዝርጋታ።
🔸በብረት ማጋጠሚያወች ተጠቅመን የብረት ኮንዲዩቶችን እናገናኛለን።
🔸ለንግድ ህንፃዎችና ለትላልቅ ህንፃዎች ኤሌክትሪክ ገመድ/ኬብል በውስጡ በማሳለፍ ለመዘርጋት ይጠቅማል።
🔸አሁን ላይ እየቀረ ያለ የኮንዲዩት አይነት ነው።
👇👇👇👇👇
https://t.me/engineer03

🔹🔸🔹ለ. ታጣፊ የብረት ኮንዲዩት (Flexible Steel Conduit):-

🔹ለገበያ የሚቀርበው በጥቅል ሲሆን አንዱ ጥቅልም እስከ 50 ሜትር እርዝመት አለው።
🔸 ለማጉበጥ/ለማጠፍ መሳሪያ አያስፈልግም።
🔹እረጅም እርቀት ላለው እና ሞቃት ለሆነ ቦታ ከፍተኛ ጥቅም አለው።

ይቀጥላል .....
👇👇👇👇👇 https://t.me/engineer03

#የኢትዮጵያ የህንፃ ኮድ መመሪያ/EBCS:-
☑️የኢትዮጵያ የህንፃ ኮድ መመሪያ/EBCS(Ethiopian Building Cod Standard) ላይ ብዙ ደንቦችና መመርያዎች የተዘረዘሩ ሲሆን በኤሌክትሪክ መስመር ዝርጋታው ዘርፍ ደግሞ የኤሌክትሪክ ገመድ ቀለም ደንብ(Electrical Wire and cable color code) ፣የኤሌክትሪክ ገመድ መጠን(Electrical Wire Size) እና የኤሌክትሪክ አክሰሰሪዎች ከመሬት ያላቸው ከፍታ(Electrical Accessories Height from floor) ዋና ዋናወቹ ናቸው።

ይጠብቁን ........

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👉Advance Security and
Performance Security 👆👆👆

.
1. Advance security
*ስራ ተቋራጩ ለሚወስደው የቅድም ክፍያ ገንዘብ በሚከፈለው የገንዘብ መጠን ልክ የሚያሲዘው የባንክ ዋስትና
ቦንድ ነው።
እውነተኛነቱ በተረጋገጠ ቼክ፣ ያልተገደበ የባንክ ዋስትና ወይም ከህጋዊ ጥቃቅን ማይክሮ ፋይናንስ የተፃፈ የዋስትና ደብዳቤ ማስያዝ ይኖርበታል።
ስራ ተቋራጩ የወሰደውን ቅድመ ክፍያ ከፍሎ እስኪጨርስ ያስያዘው ዋስትና ግዜው ማለቅ(Expire) አይችልም።
ከአንድ ወር ቀደም ብሎ የዋስትና ቀነ ገደቡ ከማለፉ በፊት ከአማካሪ በሚፃፍለት ደብዳቤ መሰረት ሊታደስ ይገባል።
ነገር ግን ስራ ተቋራጩ ያስያዘውን ዋስትና ቀነ ገደቡ አልፎ ሳያሳድስ ቢቀር ቀሪ ያልተከፈለ ቅድመ ክፍያ ሙሉ ለሙሉ ከሚቀጥለው ክፍያ ቅፅ ላይ ተቀናሽ ይደረጋል።
ስራ ተቋራጩ ያስያዘውን ዋስትና ቅድመ ክፍያ ገንዘብ ከፍሎ እንደጨረሰ ተመላሽ ይደረግለታል።
የተለየ የቅድመ ክፍያ እና የዋስትና አከፋፈል አካሔድ ለፕሮጀክቱ የተዘጋጀው ውል/special condition of contract/ ይችላል።
2. Performance Security
*ስራ ተቋራጩ ውል ተቀብሎ ተፈፃሚ ማድረግ የሚችልበትን ለብቃት ማረጋገጫ የሚያሲዘው ዋስትና ነው።
ውል በተፈራረመ በአስራ አምስት ቀናት ውስጥ (15) ውሉ የሚያዘውን መጠን ዋስትና ያቀርባል ።
ዋስትናው ስራ ተቋራጩ በተገቢው መንገድ ውሉን ተፈፃሚ ሳያደርግ ቢቀር ለውል ሰጪ (ባለቤት) እንደ ካሳ ክፍያ ይሆናል።
እውነተኛነቱ በተረጋገጠ ቼክ፣ የባንክ ዋስትና ወይም ከህጋዊ ጥቃቅን ማይክሮ ፋይናንስ የተፃፈ የዋስትና ደብዳቤ ውሉ ላይ
በተቀመጠው ፎርማት መሰረት ማስያዝ ይኖርበታል።
ይህ ዋስትና ሳይቀርብ ምንም አይነት ክፍይ ተፈፃሚ ሊደረግ
አይገባም።
ስራው ተጠናቆ እስኪያልቅ ይህ ዋስተና ተገቢ እና ቀነ ገደቡ ሳያልቅ መታደስ ይጠበቅበታል። ስራው ተጠናቆ ርክክብ እንደተፈፀመ በ ሀያ ስምንት(28) ቀናት ውስጥ ለስራ ተቋራጩ ሊመለስለት ይገባል። .
⚡አሁኑኑ Join በማረግ እና ለጓደኛዎ እና ለሚያቁት ሁሉ ሼር ያድርጉ።
👇👇👇
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Box Girder Bridge Construction

A box girder bridge (also known as a Box Section Bridge) is a bridge in which the main beams comprise girders in the shape of a hollow box. The box girder normally comprises either prestressed concrete, structural steel, or a composite of steel and reinforced concrete. The box is typically rectangular or trapezoidal in cross-section. Box girder bridges are commonly used for highway flyovers and for modern elevated structures of light rail transport. Although normally the box girder bridge is a form of beam bridge, box girders may also be used on cable-stayed bridges and other forms.

#የኤሌክትሪክ ገመድ ቀለም ደንብ(Electrical Wire and cable color code):-
☑️ኤሌክትሪክ ገመዶችን ቀለማቸውን መሰረት በማድረግ ለተለያዩ የዝርጋታ አይነቶች ማዋል አስፈላጊ ነው። በዘፈቀደ አይዘረጉም። በዚህም መሰረት የኢትዮጵያ የህንፃ ኮድ ደንቦችን እናያለን።
☑️ገመድ ስንጠቀምም ለነጠላ ፌዝ(እሳት)ና ለባለ 3 ፌዝ(እሳት) የምንጠቀማቸውን እናያለን።
⚪️ነጠላ ፌዝ/እሳት (Single phase):-
☑️3 የተለያየ ቀለም ያላቸው ገመዶች አሉት። እነርሱም:-
▶️ ለእሳት(phase)
🔴ቀይ(red)
🟡ቢጫ(yellow)
🔵ሰማያዊ(blue) ልንጠቀም እንችላለን።
▶️ ለውሃ(Neutral)
⚫️ጥቁር(black)
▶️ለግራውንድ(Ground/Earthing)
🔰አረንጓዴ በቢጫ(green&yellow)
⚪️ባለ 3 ፌዝ/እሳት(3-phase):-
☑️4 ወይም 5 የተለያየ ቀለም ያላቸው ገመዶች አሉት። እነርሱም:- ሶስት እሳት(R, Y & B)፣ አንድ ውሃና አንድ ግራውንድ ሲሆኑ ቀለማቸው እንደሚከተለው ነው።
▶️ 3ቱ እሳቶች(phases)
🔴 R-ቀይ(Red)
🟡Y-ቢጫ(Yellow)
🔵B-ሰማያዊ(Blue)
▶️ውሃ(Neutral)
⚫️ጥቁር(Black)
▶️ግራውንድ(Ground)
🔰አረንጓዴ በቢጫ(Green&Yellow)
ናቸው።

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Width of carriageway

🛣 Single lane road:- 3.75 m

🛣 Double lane road without kerb:- 7 m

🛣 Double lane road with kerb:- 7.5 m

🛣 Intermediate lane:- 5.5 m

🛣 Multi-lane roads:- 3.5 m/lane

🛣 Min. Shoulder width:- 2.5 m

🛣 Max width of any vehicle:- 2.44 m

🛣 Min. Roadway width on single lane bridge:- 4.25 m👇👇👇👇👇 https://t.me/engineer03

Types of Admixtures Used In Concrete
Admixtures are natural or manufactured chemicals which are added to the concrete before or during mixing. The most often used admixtures are air-entraining agents, water reducers, water-reducing retarders and accelerators.
We'll discuss The Types of Concrete Admixtures in the following Posts.
Source; TheConstructor
1- Water Reducing Admixtures
Water reducing admixtures, the name itself defines that they are used to minimize the water demand in a concrete mix. Workability is the important property of concrete which is improved with the addition of water but if the water is added more than required the strength and durability properties of concrete gets affected.
In addition, to increase in workability it also improves the strength of concrete, good bond between concrete and steel, prevents cracking, segregation, honeycombing, bleeding etc. Water reducing admixtures are also called as plasticizers and these are classified into three types namely plasticizers, mid-range plasticizers and superplasticizers. Normal plasticizer reduces the water demand by up to 10%, mid-range plasticizers reduce the water demand by up to 15% while superplasticizers reduce the water demand by up to 30%.

2- Retarding Admixtures
Retarding admixtures slow down the rate of hydration of cement in its initial stage and increase the initial setting time of concrete. These are also called as retarders and used especially in high-temperature zones where concrete will set quickly. The quick setting in some situations may lead to discontinuities in structure, the poor bond between the surfaces creates unnecessary voids in concrete etc. Retarders are useful to eliminate this type of problems. Commonly used retarding admixture is calcium sulphate or gypsum. Starch, cellulose products, common sugar, salts of acids are some other retarders. Most of the water-reducing admixtures are also acts as retarding admixtures and they are called as retarding plasticizers.

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Civil Engineering Sub-Disciplines

⚗⚗⚗⚗⚗⚗⚗⚗⚗⚗⚗⚗
1.Coastal engineering is concerned with managing coastal areas. The term coastal defense is the more traditional term, but coastal management has become more popular as the field has expanded to include techniques that allow erosion to claim land.
🏗🏭🏗🏭🏗🏭🏗🏭🏗🏭🏗🏭
2.Construction engineering involves planning and execution of the designs from transportation, site development, hydraulic, environmental, structural and geotechnical engineers.
🗾🗾🗾🗾🗾🗾🗾🗾🗾🗾🗾🗾
3.Earthquake engineering is dedicated to reducing earthquake risk by advancing the practice of this science.
🏞🏞🏞🏞🏞🏞🏞🏞🏞🏞🏞🏞
4.Environmental engineering can be involved with pollution reduction, green engineering, and industrial ecology and involves protecting the environment and human health.
⛰🏔⛰⛰⛰🏜🏜⛰🏜🏜⛰🏜
5.Geotechnical engineering is an area of civil engineering concerned with the rock and soil that supports civil engineering projects.
⛲️🗼⛲️🗼⛲️🗼⛲️🗼⛲️🗼⛲️🗼
6.Materials engineering and sciences deals with materials such as concrete, mix asphalt concrete, metals as well as paints and finishes.
🏚🌅🏜🏭🌄🏭🏜🏭🏜🏭🏜🏭
7.Municipal or urban engineering involves specifying, designing, constructing, and maintaining streets, sidewalks, water supply networks, sewers, street lighting, municipal solid waste management and disposal, storage depots for various bulk materials used for maintenance and public works, public parks and bicycle paths.
⛩🚧🏗🏣🏤🏢🏗🏪🏚🏗🗼⛩
8.Structural engineering is concerned with designing structures to be safe and serviceable for their users
🛣🌉🛣🌉🛣🌉🛣🌉🛣🌉🛣🌉
9.Transportation engineering is concerned with moving people and goods efficiently, safely, and in a manner conducive to a vibrant community.
🏞⚓️⛲️⚓️⛲️🏝⚓️⛲️⚓️⛲️⚓️⛲️
10.Water resources engineering is a discipline that combines hydrology, environmental science, meteorology, geology, conservation, and resource management.

🏰🗼🏰🗼🏰🗼🏰🗼🏰🗼🏰🗼

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#EthiopiaAddisAbeba
ጀሞ ቁጥር ሁለት አካባቢ ባለ አራት የኮንክሪት ወለል (G+3) ለመኖሪያ የተሠራ ህንጻ ወድቋል።

ከአወዳደቁ መረዳት እንደሚቻለው ከፊት ለፊት ያሉት ዐምዶች (columns) የመሸከም አቅማቸውን (buckling poin5) ያለፈ ሸክም ተጭኗቸዋል። በሕንጻ ዲዛይን ሳይንስ የዐምድ (Columns) መፍረስ አልፎ አልፎ (Rarely) የሚከሰት እንጂ የዘወትር ክስተት አይደለም። በተለምዶ በመሐንዲሶች ዘንድ "ዐምድ ወድቆ አይወድቅም" ይባላል።

ሕንጻ በተለያዩ ምክንያቶች ሊወድቅ ይችላል። ለምሳሌ ከመዋቅር ዲዛይን ችግር፣ የአሸዋ መቆሸሽ፣ የሲሚንቶ ማነስ፣ በቂ ውኃ ያለማጠጣት ወዘተ ሊሆንም ይችላል።

ለባለሙያ የዲዛይን ጥናት የፕሮጀክቱን 1% የማይሞላ ገንዘብ ላለመክፈል ግንባታውንም በባለሙያ ለማሠራት መስቆንቆን እንዲህ 100% ዋጋ ያስከፍላል።

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.


Types of Admixtures Used In Concrete ...con’t...from the above

3- Accelerating Admixtures

Accelerating admixtures are used to reduce the initial setting time of concrete. They speed up the process of the initial stage of hardening of concrete hence they are also called as accelerators. These accelerators also improve the strength of concrete in its early stage by increasing the rate of hydration. Earlier hardening of concrete is useful in several situations such as early removal of formwork, less period of curing, emergency repair works, for constructions in low-temperature regions etc. Some of the accelerating admixtures are triethanolamine, calcium formate, silica fume, calcium chloride, finely divided silica gel etc. Calcium chloride is the cheap and commonly used accelerating admixture.

4- Air Entraining Concrete Admixture

Air entraining admixtures are one of the most important inventions in concrete technology. Their primary function is to increase the durability of concrete under freezing and thawing conditions. When added to the concrete mix, these admixtures will form millions of non-coalescing air bubbles throughout the mix and improves the properties of concrete. Air entrainment in concrete will also improve the workability of concrete, prevents segregation and bleeding, lower the unit weight and modulus of elasticity of concrete improves the chemical resistance of concrete and reduction of cement or sand or water content in concrete etc. Most used air entrainment admixtures are visual resin, darex, Teepol, Cheecol etc. These admixtures are actually made of Natural wood resins, alkali salts, animal and vegetable fats and oils etc.


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Types of Admixtures Used In Concrete ...cont...

5- Pozzolanic Admixtures

Pozzolanic admixtures are used to prepare dense concrete mix which is best suitable for water retaining structures like dams, reservoirs etc. They also reduce the heat of hydration and thermal shrinkage. Best pozzolanic materials in optimum quantity give the best results and prevent or reduces many risks such as alkali-aggregate reaction, leaching, sulfate attack etc. Pozzolanic materials used as admixtures are either natural or artificial. Naturally occurring Pozzolanic materials are the clay, shale, volcanic tuffs, pumicite, etc. and artificial pozzolans available are fly ash, silica fume, blast furnace slag, rice husk ash, surkhi etc.

6- Damp-proofing Admixtures

Damp-proofing or waterproofing admixtures are used to make the concrete structure impermeable against water and to prevent dampness on the concrete surface. In addition to the waterproof property, they also act as accelerators in the early stage of concrete hardening. Damp proofing admixtures are available in liquid form, powder form, paste form etc. The main constituents of these admixtures are aluminium sulfate, zinc sulfate aluminium chloride, calcium chloride, silicate of soda etc. which are chemically active pore fillers.
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Following are the tests conducted to determine the suitability of stone for
engineering use

👉Acid Test: understand the presence of CACO3 in building stone.

👉Attrition Test: Resisting power of stones against grinding action or wear and tear against the traffic.

👉Crushing Test: Compressive strength of stones.

👉Impact Test: resistance of stones against sudden loading.

👉Smith's Test: presence of soluble matter in stones.

👉Water Absorption Test: To check how much water the stone may absorb.

👉Hardness Test: To
determinethe surface abrasion resistance of stone.

👉Microscopic Test:
To check grain size, texture, pores, shakes etc of stone.

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Topic: #Surveying


#SPECIAL_METHODS_OF_SPIRIT_LEVELLING

🎓 #Differential_levelling: it is the method of direct levelling the object of which is solely to determine the difference in elevation of two point regardless of the horizontal positions of the point with respect of each other. When the points are apart, it may be necessary to set up the instruments serveral times. This type of levelling is also known as fly levelling.

🎓 #Profile_levelling: It is the method of direct-levelling the object of which is to determine the elevations of point at measured intervals along a given line in order to obtain a profile of the surface along that line.

🎓 #Cross-sectioning: cross-sectioning or cross-levelling is the process of taking levels one each side of a main line at right angles to that line, in order to determine a vertical cross-section of the surface of the ground, or of underlying strata, or of both.

🎓 #Reciprocal_levelling: It is the method of levelling in which the difference in elevation between two points is accurately determined by two sets of reciprocal observations when it is not possible to set up the level between the two points.

🎓 #Precise_levelling: It is the levelling in which the degree of precision required is too great to be attained by ordinary methods, and in which, therefore, special equipment or special precautions or both are necessary to eliminate, as far as possible, all sources of error

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