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johnmoeeain
08-10-2009, 05:37 PM
အစ္မေရ... Tezargyi ရဲ႕ Bearing Capacity ကို တြက္ဖို႔ ခ်ဥ္းကပ္တဲ႔ Approach ကို ရွင္းျပေပးပါလား...

ကြၽန္ေတာ္တို႔ Design ကိုစဥ္းစားရင္ ရမယ့္ ခံႏိုင္မယ့္ Soil ရဲ႕ Strength ကိုပဲ.. သြား သြား input ေပးေနတာ
ေနာက္ပိုင္း data ေလးေတြ စံုလာရင္ ကိုယ္ ထည့္လိုက္တဲ့ input ေတြကို check လုပ္ရင္ လုပ္တတ္ေအာင္လို႔...
မဟုတ္ရင္ ကိုယ့္ဆီ ေရာက္လာႏိုင္တဲ့ Soil Data ကိုပဲ ယံုလိုက္ရေတာ့မယ္ေလ.. Tezargyi ေရာ ေနာက္ Mayerhof ေရာ.. သူတို႔ရဲ႕
ီDesign တြက္ဖို႔ ဘာေတြ လုိအပ္မယ္.. ေနာက္ (ျဖစ္ႏုိင္ရင္ေတာ့ အစ္မရယ္) ဘယ္လို တြက္မယ္ ဆိုတာေလးေတြေရာေပါ့.. :4:

ေၾသာ္... သူမ်ားကိုပဲ ခိုင္းေနတာေတာ့ မဟုတ္ဖူးေနာ္.. ကြၽန္ေတာ္ ဖတ္လိုက္တိုင္း နားမလည္လာလို႔...
ဒီေန႔ နားလည္လိုက္တာနဲ႔ မေန႔က နားလည္ထားလိုက္တာေတြေတာင္ လြဲေနေတာ့ေလ...... :?

(Soil Mechanic သမားမ်ားကို ေစာ္ကားၿပီး ေျပာတာ မဟုတ္ဖူးေနာ္) :haha:

ွSoil ဆိုတာ ဘယ္လိုမွကို ယံုၾကည္ထားလိုက္လို႔ မရတာ လူတိုင္းခံစားလို႔ ရတယ္မဟုတ္လားေလေနာ္..... :haha: :haha:

chitsuelay
08-10-2009, 09:10 PM
Tezargyi ရဲ႕ Bearing Capacity ကို တြက္ဖို႔ ခ်ဥ္းကပ္တဲ႔ Approach ကို ရွင္းျပေပးပါလား...

Terzaghi ကေအာက္မွာေျပာထားတဲအခ်က္ေတြကို ယူဆထားပါတယ္။
1. Df < B (Footing ရဲေျမေအာက္ထဲမွာရွိတဲအနက္က Footing ေအာက္ေျခအက်ယ္ ထက္နဲရပါမယ္။)
2. General Shear Failure ျဖစ္တယ္လိုယူဆထားျခင္း။
3. Footing ရဲေအာက္ေျခမွာျဖစ္ေပၚတဲ ၾတိဂံပံု shear ဧရိယာမွာရွိတဲ ေထာင့္ရဲတန္ဖိုးကို friction angle(phi) တန္ဖိုးအတိုင္း ယူဆျခင္း။
4. Footing ေအာက္ေျခရဲ အေပၚဘက္မွာရွိတဲ ေျမၾကီးရဲ shear strength ကို neglect လုပ္ထားျခင္း။
5. Footing ေအာက္ေျခရဲ အေပၚဘက္မွာရွိတဲ ေျမၾကီးကို surcharge ( surcharge = rDf ) အျဖစ္ အစားထိုးထားျခင္း။
6. Footing ေအာက္ေျခကို ညီညာေခ်ာမြတ္ျခင္းမရွိေသာ မ်က္နာျပင္ဟု ယူဆျခင္း။
Meyerhof ကေတာ့ Terzaghi ရဲ နံပါတ္ ၄ အခ်က္ကို neglect မလုပ္ပဲထည္သြင္းစဥ္းစားထားျခင္းပဲျဖစ္ပါတယ္ (ေအာက္ကပံုကိုၾကည့္ပါ)။ ဒါေၾကာင္ Meyerhof's equation မွာ depth factor ပိုလာရျခင္းျဖစ္တယ္။

http://img200.imageshack.us/img200/1668/1fig.jpg (http://img200.imageshack.us/i/1fig.jpg/)

Equation ေလးေတြကိုေတာ့ Soil Mechanics and Foundation By Muni Budhu စာအုပ္ကေန ကူးျပီးေဖာ္ျပေပးလိုက္ပါတယ္။
Terzaghi's Bearing Capacity Equation
http://img188.imageshack.us/img188/631/2terz.jpg (http://img188.imageshack.us/i/2terz.jpg/)

Meyerhof's Bearing Capacity Equation
http://img29.imageshack.us/img29/2961/3meyer.jpg (http://img29.imageshack.us/i/3meyer.jpg/)

AndrewSway
08-14-2009, 09:32 AM
ကို johnmoeeain
Geotechnical Engineer တေယာက္အေနနဲ ့ foundation design data ေပးတဲ ့အခါ တြက္နည္း တခုထဲနဲ ့ ေပးေလ ့မရိွ ပါ။ Theoretical solution ၂ ခု၃ ခု ေလာက္ နဲ ့တြက္ျပီး ရလာတဲ ့data ကိုတခါ empirical and semi-empirical methods (Alpan method, Meyerof method) တို ့နဲ ့check လုပ္ျပီးမွ Final Answer ကုိ ေပးေလ ့ရိွပါတယ္။ ေနာက္ျပီး ေျမအမ်ိုဳးအစားကို လိုက္ျပီး တြက္နည္းအမ်ိုဳးမ်ိဳးသံုးတတ္ပါတယ္။ ဥပမာေျပာရ ရင္ Sandy soil ဆို ရင္ Alpan's method, Schultz Approximation, Modified Terzaghi&Peck, Schmertmann, Bazaraa စသျဖင္ ့သံုးျပီး Clayey soil ဆိုရင္ Janbu, Perloff စသျဖင္ ့လည္းသံုးၾကပါတယ္။ အခ်ိန္ေပးနိင္ရင္ FEM နဲ ့ထပ္တြက္ျပီးလည္းေပးတတ္ပါတယ္။
Structural Engineer တေယာက္အေနနဲ ့Geotech ကေပးလာတဲ ့Data ကို check လုပ္ၾကည္ ့ခ်င္တယ္ဆို ရင္ empirical solution ကို သံုးတာအခ်ိန္ကုန္သက္သာနိုင္ပါတယ္။
ေဟာဒီ link မွာ shallow foundation ကို အလြယ္တကူနဲ ့တြက္ၾကည္ ့နိုင္ပါတယ္။
http://foundation.union.edu/

မခ်စ္ဆူး
ဒီ ေဆြးေႏြးခ်က္ဟာတင္ထားတဲ ့topic နဲ ့လြဲေနတယ္ထင္ပါတယ္။ Shallow foundation နဲ ့ပါတ္သက္ျပီး ပို က်ယ္က်ယ္ျပန္ ့ျပန္ ့ေဆြးေႏြးနိုင္ေအာင္ topic အသစ္အေနနဲ ့ေျပာင္းလို ့ရရင္ ေျပာင္းေပးပါလား။

ATS

NayNyo
08-14-2009, 01:28 PM
အဟီး.....ကုိဂၽြန္မိုးအိမ္ နဲ႔ မခ်စ္ဆူး တဲ႔ :2: :2: :2:

ဟုိႏွစ္ေယာက္ေတာ႕ တစ္ေယာက္နဲ႔ တစ္ေယာက္ ဖက္္ျပီး ငုိေနေတာ႕မွာပဲ။ :'( :'(

မဂၽြန္မုိးအိမ္ နဲ႔ မခ်စ္စုေလး ပါ။
၀င္ေရာက္ေဆြးေႏြးေပးတာ ေက်းဇဴးအမ်ားၾကီးတင္ပါတယ္။

chit tee
08-14-2009, 02:55 PM
ဒီလို ေခါင္းစဥ္တတ္လိုက္ၿပီးဆိုမွေတာ့
ဘယ္လိုမ်ဳိးဟာက Shallow Foundation လဲ
အဲ့ဒါေၾကာင့္ ... တေနရာကေတြ႕လို႕မွတ္ထားဖူးတာေလးကို ျပန္ေျပာျပမယ္ေနာ္ ။

SHALLOW FOUNDATION
- a type of foundation that is used when the earth directly beneath a structure has sufficient bearing capacity to sustain the loads from the structure

SHALL FOUNDATION ေအာက္မွာ တခါထပ္ခြဲရမယ္ဆိုရင္ေတာ့ အၾကမ္းဖ်င္းအားျဖင့္ ...

(1) Cantilever Wall - a type of foundation wall that consists of a stem and a base slab that is held in equilibrium by self-weight,
horizontal soil pressure, and the reaction of the base structure acting upward

(2) Combined Footing - a footing that is used under two or more vertical elements to prevent overturning from eccentric loading

(3) Mat/Raft Foundation - a large slab foundation that is used instead of multiple spread footings

(4) Spread Footing - the most widely used type of shallow foundation that is designed to receive the concentrated loads directly on the centroid
to prevent unequal pressure distribution and overturning of the footing

(5) Strip Footing - an extended footing used under foundation walls; strip footings are used in basements, crawlspaces, and for slabs-on grade.

(6) Wall Footing - elongated spread footings that transfer loads from load bearing walls. Wall footings are used in substructures such as slabs-on-grade,
crawlspaces and basements.

တျခား အဓိပၸါယ္ဖြင့္ဆိုခ်က္ေတြလဲ အမ်ဳိးမ်ဳိးရွိၾကမွာပါ။ ေအာက္မွာလဲသြားၾကည့္လို႕ရပါတယ္ ။
၀ီကီမွာ သြားၾကည့္မယ္ဆိုရင္ေတာ့ .....
http://en.wikipedia.org/wiki/Shallow_foundation

ကို AndrewSway အႀကံျပဳတဲ့အတိုင္း ေခါင္းစဥ္ကို ျပန္လည္ခြဲလိုက္ပါတယ္ ။ အဲ့ဒီအေတြ႕အႀကံဳေလးေတြ အားရပါးရ ေဆြးေႏြးေပးဖို႕ ေတာင္းဆိုပါရေစ

AndrewSway
08-14-2009, 10:50 PM
ဆရာခ်စ္
Shallow နဲ ့ Deep ကို topic သတ္သတ္ခြဲ ေပးနိုင္ရင္ေကာင္းမယ္ထင္ပါတယ္။ ကြ်န္ေတာ္ ၂ နွစ္ေလာက္ shallow မလုပ္ဘဲ Deep foundation design ဘဲ လုပ္ခဲ့ ရသလို ၃ ႏွစ္ေလာက္ deep မလုပ္ဘဲ shallow design ဘဲ လုပ္ခဲ ့ရတဲ ့အခ်ိန္ေတြရိွခဲ ့ဘူးလို ့ပါ။ သတ္သတ္စီဆိုေတာ ့ မေရာမေထြးဘဲေဆြးေႏြးနိုင္မယ္ထင္လို ့ပါ။

အရင္က MIT မွ shallow foundation နဲ ့ပါတ္သက္ျပီး Open Lecture တင္ထားတာရိွပါတယ္။ အခုမရိွေတာ ့ပါ။ Soil Mechanics ဘဲ ရိွပါေတာ့တယ္။ စိတ္၀င္စားသူမ်ား ေအာက္က Link မွာ သြားၾကည့္ နိုင္ပါ တယ္။

http://ocw.mit.edu/OcwWeb/Civil-and-Environmental-Engineering/index.htm

အရင္ က Texas A&M မွ shallow foundation video lecture series မ်ား တင္ထားေသာ္လည္း အခုရွာမရေတာ ့ပါ။ India က နံမည္ၾကီး IIT က တင္ထားတဲ ့ video lecture မ်ားကို ေတာ ့စိတ္၀င္စားသူမ်ား ေအာက္ က Link မွာ သြားၾကည့္နိုင္ပါတယ္။

http://www.youtube.com/watch?v=H6_J8LuTa-M

chitsuelay
10-29-2009, 10:22 AM
Shallow Foundation ရဲ့အားသာခ်က္နဲ႕အားနည္းခ်က္ ေလး အခ်ိဳ႕ပါ။

ADVANTAGES OF USING SHALLOW FOUNDATION
1- Cost (affordable)
2- Construction Procedure (simple)
3- Materials (mostly concrete)
4- Labor (does not need expertise)

DISADVANTAGES OF USING SHALLOW FOUNDATION
1- Settlement
2- Limit Capacity * Soil * Structure
3- Irregular ground surface (slope, retaining wall)
4- Foundation subjected to pullout, torsion, moment.

chitsuelay
10-29-2009, 03:50 PM
ကိုယ္တြက္ထားတဲ့ ေျမသားရဲ့ Bearing Capacity ရဲ့ result ကိုစစ္ၾကည့္ခ်င္ရင္ပဲျဖစ္ျဖစ္ ,
သက္ေရာက္မဲ့ pressure ကိုသိလို႕ ျမန္ျမန္ဆန္ဆန္ အၾကမ္းျဖင္း အဆင္ေျပမေျပ စစ္ခ်င္ရင္ပဲျဖစ္ျဖစ္ ,
Foudation ရဲ့ size ကို အၾကမ္းျဖင္း သိခ်င္လို႕ပဲျဖစ္ျဖစ္

non-cohesive(sandy) နဲ႕ cohesive(clayey) တို႕အတြက္ ေျမသားရဲ့ Bearing Capacity ရဲ့ တန္ဖိုးေတြကို ေအာက္ပါဇယားကေန လြယ္တကူ အၾကမ္းျဖင္း သိရွိႏိုင္ပါတယ္.

http://img88.imageshack.us/img88/415/bearingcapacityforsoil.jpg (http://img88.imageshack.us/i/bearingcapacityforsoil.jpg/)

chit tee
10-30-2009, 11:13 AM
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chit tee
10-30-2009, 11:15 AM
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10-30-2009, 11:17 AM
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chit tee
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10-30-2009, 12:47 PM
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chit tee
11-01-2009, 02:10 PM
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chit tee
11-01-2009, 04:06 PM
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chit tee
11-02-2009, 07:30 PM
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chit tee
11-02-2009, 07:33 PM
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chit tee
11-02-2009, 07:40 PM
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chit tee
11-02-2009, 07:41 PM
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chit tee
11-02-2009, 07:44 PM
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chit tee
11-02-2009, 07:46 PM
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chit tee
11-02-2009, 07:48 PM
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chit tee
11-02-2009, 07:51 PM
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chit tee
11-03-2009, 07:54 PM
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chit tee
11-03-2009, 07:56 PM
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chit tee
11-03-2009, 09:15 PM
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chit tee
11-03-2009, 09:17 PM
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chit tee
11-04-2009, 01:20 PM
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chit tee
11-04-2009, 01:22 PM
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chit tee
11-04-2009, 01:26 PM
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chit tee
11-04-2009, 01:31 PM
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chit tee
11-04-2009, 02:14 PM
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chit tee
11-04-2009, 02:29 PM
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chit tee
11-05-2009, 01:51 PM
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chitsuelay
11-27-2009, 02:17 PM
Singapore, LTA (Land Transport Authority) က Foundation (Shallow & Deep) အတြက္ ခြင့္ျပဳထားတဲ့ Settlement နဲ႕ Horizontal deflection တန္ဖိုးေလးေတြပါ။ အလြယ္တကူ Reference လုပ္ႏိုင္ေအာင္ပါ။


http://img442.imageshack.us/img442/7855/foundationallowsettleme.jpg (http://img442.imageshack.us/i/foundationallowsettleme.jpg/)

neonlm
12-01-2009, 12:18 PM
မခ်စ္စု ရဲ႕ allowable total and differential settlement value ေတြကပိုတင္းၾကပ္ေနတယ္ထင္တယ္ဗ်။ ေလာေလာဆယ္ reference စာအုပ္ကအနားမွာမရွိေတာ့ စာအုပ္လွန္ၾကည္႕လုိ႕မရလုိ႕။ကၽြန္ေတာ္ထင္တာမမွားဘူးဆိုရင္ :4: differential settlement 1:250 ဒါမွမဟုတ္ရင္ 1:500 ဆိုတာ Normal structure ေတြအတြက္အလြန္ဆုံးထင္တာဘဲ။ Total ကအမ်ားဆုံး 50 mm ထင္တာဘဲ။ (ကၽြန္ေတာ္က EC7 ကုိအေၿခခံေၿပာေနတာပါ။) HDB residential housing project ေတြအတြက္ေတာ့ 1:500 နဲ႕ 25mm လုိ႔ကန္႕သတ္ထားတယ္။ LTA structure ေတြက deflection နဲ႕ angular rotation (beta) ကုိပိုၿပီး sensitive ၿဖစ္ေနတာလား ဒါမွမဟုတ္ column loading ေတြဘဲအရမ္းကြာၿခားခ်က္မ်ားလုိ႕လား၊ ဒါမွမဟုတ္ dynamic loading ေၾကာင့္လား၊ ပိုအေရးၾကီးတဲ့ public structure ေတြၿဖစ္တာေၾကာင့္လား သိရင္ေၿပာေပးပါအုံး။

neonlm
12-01-2009, 02:33 PM
ေနာက္တခုစဥ္းစားမိတာက .... ဒီ differential settlement ဆိုိိတာၾကီးကုိ ကၽြန္ေတာ္ site supervisor တေယာက္အေနနဲ႕floor တခုၿပီးတုိ္ိင္း surveyor ဆီက report ကုိေစာင့္ၿပီး monitor လုပ္ပါလုိ႕ QP ကခုိင္းထားလုိ႕သာ ေစာင့္ၾကည္႕ေနရတာ ....project ၂ ခုေလာက္သာၿပီးသြားတယ္...report ကအၿမဲ OK ေနေတာ့ဘာမွၿပႆနာမေပၚခဲ့ဘူး။ တကယ္လုိ႕ အဲဒီ ...differential settlement ေတြက allowable limit ေတြထက္ေက်ာ္ကုန္ၿပီဆိုပါေတာ့ ...အဲဒါဆိုကၽြန္ေတာ္တုိ႕ဘာေတြလုပ္သင့္လဲ သိတဲသူေတြေၿပာၿပေပးပါအုံး။ (ဟုတ္ပါတယ္။အဲဒီအခ်ိ္န္ဆိုရင္လဲ ကၽြန္ေတာ့္QP ကဘဲ solution ကုိစဥ္းစားမွာပါ။ကၽြန္ေတာ္က သူခုိင္းတာလုပ္ေပးရုံပါဘဲ။ ဒါေပမဲ့ ဘယ္လုိ option ေတြရွိလဲဆုိတာသိခ်င္လုိ႕။) ကၽြန္ေတာ္ (လူျပိန္းတေယာက္အေနနဲ႕ ဥာဏ္မွီသေလာက္လုပ္ဆိုရင္) settlement နဲေနတဲ့ column ေတြကုိ ညီသြားေအာင္ loading ေတြနဲ႕ထပ္ဖိပစ္မွာဘဲ။ :4:

chitsuelay
12-01-2009, 04:06 PM
construction မစခင္မွာ computer software နဲ႕ analysis လုပ္ၾကည့္တဲ့အခါdifferential settlement ဟာ ခြင့္ျပဳထားတာထက္ ေက်ာ္ေနမယ္ဆိုရင္ ေဖာင္ေဒးရွင္း ရဲ့ေအာက္မွာ compensating grouting ထည့္သြင္းေလာင္းထားျခင္းျဖင့္လဲ construction ျပဳလုပ္ေနစဥ္ကာလအတြင္း settlement မ်ားခြင့္ျပဳထားတာထက္မေက်ာ္ေအာင္ ၾကိဳတင္ကာကြယ္ထားပါတယ္။ (အျခားနည္းမ်ား ကိုလဲ သိတဲ့သူေတြေရးၾကပါဦးေနာ္)

Compensating Grouting
http://img109.imageshack.us/img109/6770/comgr.jpg (http://img109.imageshack.us/i/comgr.jpg/)



အိမ္က ဒီလိုေစာင္းသြားတယ္ဆိုရင္ ေစာင္းသြားတဲ့ဘက္က ေဖာင္ေဒးရွင္း ရဲ့ေအာက္ကို grouting (Jet Grouting or Underpinning) လုပ္ေပးျပီး ျပန္ျမင့္ယူႏိုင္ပါတယ္။

http://img130.imageshack.us/img130/3342/differentailsettlement.jpg (http://img130.imageshack.us/i/differentailsettlement.jpg/)

http://img130.imageshack.us/img130/7251/jetgroutingunderpin.jpg (http://img130.imageshack.us/i/jetgroutingunderpin.jpg/)

AndrewSway
12-03-2009, 07:21 AM
ီီDifferential Settlement အတြက္အေကာင္းဆံုး (ေစ်းအသက္သာဆံုး) ကေတာ ့compaction လုိ ့ဘဲထင္ပါတယ္။ Sandy top soil ရိွတဲ ့ေနရာမ်ိုဳးဆိုရင္ေပါ ့။ Residential building အတြက္ Geotech report ေရးတဲ ့အခါ site preparation မွာ top soil ကို 2 feet ေလာက္အထိ stripped တူးထုတ္ ခိုင္းပါတယ္။ ျပီးရင္ stripped grade မွာ proof rolling ခိုင္းပါတယ္။ Subgrade proof rolling compaction ကို at least 95% of the modified proctor maximum dry density (ASTM D-1157) ကို minimum 2 feet below the stripped grade အထိ ရေအာင္လုပ္ခိုင္းပါတယ္။ ျပီးမွ fill material ကို ျဖည့္ခိုင္းပါတယ္။ Fill ကို လည္း 95% dry density ရသည္အထိ တလြွာခ်င္းroll လုပ္ခိုင္းပါတယ္။ အဲဒီလို မွမလုပ္ခ်င္ရင္ ေတာ ့ wood pile ရိုက္ခိုင္းပါတယ္။ ေဘးအိမ္ေတြရိွလို ့ vibration ျပသနာေရွာင္ခ်င္ရင္ေတာ ့stone column, aggregate pile, vibro-float, helical pile စသျဖင္ ့လည္း လုပ္ခိုင္းပါတယ္။ Commercial building ေတြေက်ာင္းေတြဆိုရင္ေတာ ့ Rapid compaction, Dynamic compaction စတဲ ့နည္းေတြရိွပါတယ္။ သူတုိ ့ကေတာ ့၁၀ ေပအနက္အထိ effect ျဖစ္နိုင္ပါတယ္။
ေဆာက္ျပိးသားအိမ္ ေတြ compaction ေသ ေသခ်ာခ်ာမလုပ္လို ့Differential Settlement ျဖစ္ရင္ေတာ ့ flow-able fill, mud jacking, poly urethane injection (chemical grouting) စသျဖင္ ့နည္းမ်ားနဲ ့controll လုပ္နိုင္ပါတယ္။ သည့္ထက္ေစ်း ၾကီးတာသံုးခ်င္ရင္ေတာ ့မခ်စ္စူးေလးေျပာတဲ ့low slump Jet Grouting or Under-Pinning တို ့လုပ္နိုင္ပါတယ္။ under-pinning ကို ေတာ ့ေစ်းျကီးသည္ ့အတြက္ structrual damage ျဖစ္မွဘဲ recommend လုပ္ပါတယ္။

Geotech engineerရဲ ့recommendation အတိုင္းေဆာက္လို ့ကေတာ ့ allowable ထက္ေက်ာ္စရာရိွမယ္မထင္ပါ။

hsu hsu
12-20-2010, 01:56 PM
MEF နဲ႕ သိတာေတြကို share လုပ္ၾကတဲ႕ သူေတြအားလံုးကို လွိဳက္လွိဳက္လွဲလွဲ ေက်းဇူးတင္ပါတယ္..

hsu hsu
12-20-2010, 02:46 PM
Terzaghi Bearing Capacity Theory ႏွင္႔ shallow foundation ကို တြက္ၾကည္႕ရာမွာ Angle of Shearing Resistance ဆို တာကိုေတြ႕ပါတယ္..ဘယ္ေလာက္ယူျပီးတြက္ရမွာပါလဲ.....က်န္တဲ႕ data ေတြ အားလံုးေတာ႕ ရွိပါတယ္..

hsu hsu
12-20-2010, 02:57 PM
Terzaghi Bearing Capacity Theory နဲ႕ တြက္ရာမွာAngle of Shearing Resistance ဆိုတာ ဘယ္ေလာက္ ယူရမွာပါလဲ..တျခား Data ေတြကေတာ႔ ရွိပါတယ္...

AndrewSway
12-21-2010, 01:20 AM
မစုျမတ္သီရိ ခင္ဗ်ား
angle of shearing resistance (internal angle of friction, angle of frictional resistance; φ,phi) ကေတာ ့ေျမအမ်ိုဳးအစား၊ relative density, moisture content, etc.. စ သည္ ့အခ်က္မ်ားေေပၚမူတည္ျပီး တန္ဘိုးအမ်ိဳးမ်ိဳးရိွနိုင္ပါတယ္။ အျခား Data ဆိုတာမ်ားလည္းေျပာျပနိုင္ရင္ေျပာျပေပးပါ။ လက္ေတြ ့ ဒီဇိုင္းလုပ္ရမွာလား အတန္းထဲက အိမ္စာအတြက္ တြက္ ရမွာလားလည္း ေျပာေပးပါ။
အလုပ္ထဲမွာ ဒီဇိုင္းလုပ္ရမွာဆုိရင္ ေတာ ့လုပ္ငန္းခြင္မွာ phi ကိုဘယ္လို ရွာတယ္ဆိုတာ မခ်စ္ဆူးေလး ရဲ ့ Geotechnical Design Paramters (Soil & Rock မ်ား၏္ r, cu, c', phi, E စသည္.... ေအာက္မွာ အၾကမ္းေဆြးေႏြးခဲ့မယ္ထင္ပါတယ္။လုပ္ငန္းခြင္မွာ ေယဘူယ်အားျဖင္ ့ယူဆနိုင္မဲ ့ phi value မ်ားကို ေအာက္ကဇယားမွလည္းရွာေဖြနိုင္ပါတယ္။


http://img691.imageshack.us/img691/7929/spt2phi.jpg

ၤFrom:http://www.geotechnicalinfo.com/angle_of_internal_friction.html

ninimar
12-21-2010, 10:28 PM
Terzaghi Bearing Capacity Theory နဲ႕ တြက္ရာမွာAngle of Shearing Resistance ဆိုတာ ဘယ္ေလာက္ ယူရမွာပါလဲ..တျခား Data ေတြကေတာ႔ ရွိပါတယ္...

http://imgur.com/616nP.jpg

Reference;
Foundation Analysis and Design (3rd Edition) pp-135 by Josephe. Bowles