Forwarded from Free Quizes
Soil Mechanics IMP
@macedhule
Maximum void ratio is 0.91(IES)
Minimum void ratio is 0.35(IES)
#void ratio & watercontent has no upper limit.
#porosity can lie within 0 to 100% but not zero and not 100%
#degree of saturation can be zero(dry soil), can be 100%(fully saturated soil, or take intermediate value(moist or partialy saturated soil)
Density index lies between 0-1
Water content can be found out most accurately by oven drying method, and in-situ by Radiation method.
If specific gravity is know then it can be found out by pycnometer also.
Core cutter method and sand replacement method are useful in finding in-situ unit weights of soil {Moist unit weight or bulk unit weight}
Specific gravity can be found out by pycnometer and indirectly by shrinkage limit.
(NOTE-Degree of saturation at shrinkage limit is 1)
For organic soils specific gravity ranges in 1.2-1.4
And for inorganic soils it is,
2.65-2.80{ex. Sand}
Sedimentation analysis consist of pipette analysis and hydrometer method
There are "3" corrections in hydrometer method.
Meniscus correction(+ve)
Deflocculating agent correction(-ve)
Temp. Correction.
+ve........ T>27ยฐC
-ve..........T<27ยฐC
Well graded soils have a greater compaction property .
Poorly garaded or uniformly graded consist of same grain size hence voids are there.
A special case of poorly graded soil is the one in which particles are either in excess or deficient called as gap graded soils! (Also called skip graded)
If D10=150 micron, it means 10% particles are finer than 150 micron. . .
Note that D10 is called effective particle size.
D50-Average size
D100- denotes the size of largest particle in the soil.
For well graded soils 1<Cc<3
For well graded gravels Cu>4
For Well Graded sands Cu>6
For poorly graded soils Cu=1
#Trick?????
G for gavaskar, S for sachin
Gavaskar four(เคเฅเคเคพ) Marto ๐
Sachin six marto๐
In casagrandes test to find liquid limit water content is found out corresponding to 25 no. Of blows
Plasticity index of sands is zero.
Toughness index is (plasticity index/flow index). . .. (#MMRDA 2015)
Sensitivity is always greater than unity and is directly proportional to thixotrophy.
Soil activity was explained by skempton.
Soil activity denotes swelling potential of soil.
@macedhule
Out of various unit weights of soils, unit weight of solids is maximum while submerged unit weight is minimum
( #Generaly submerged unit weight is only 50% of saturated weight--------- this point is related to bearing capacity---when water table rises to ground surface unit weight of water falls to 50% hence bearing capacity under submergence condition is reduced by 50%)
Plasticity and activity of montmorilonite is maximum.
Bentoninte is purest form of clay which consist of 98% clay.
Bentonite is also called drilling mud which is used as a lubricant.
@macedhule
As compared to normal soils expansive soils have
1. More liquid limit
2. Less plastic limit
3.less shrinkage limit
4.more volumetric shrinkage
5. More plasticity index( from pt. 1 & pt 2)
Clay is finer than 0.002 mm and is flacky in shape(#TRANSCO dec 2016)
@macedhule
Silt is finer than 0.075 mm and coarser than 0.002 mm
Boulders are greater than 300mm
Gravel size is greater than 4.75mm and smaller than 80mm
As per IS 1498:1970๐
coarse grained soils are classified into 8 groups while fine grained soils are classified into 10 groups
Thus there are total 18 groups
Eg.
GS would be sandy gravel
Gp - poorly graded gravel
GW- well graded gravel etc
@macedhule
@macedhule
Maximum void ratio is 0.91(IES)
Minimum void ratio is 0.35(IES)
#void ratio & watercontent has no upper limit.
#porosity can lie within 0 to 100% but not zero and not 100%
#degree of saturation can be zero(dry soil), can be 100%(fully saturated soil, or take intermediate value(moist or partialy saturated soil)
Density index lies between 0-1
Water content can be found out most accurately by oven drying method, and in-situ by Radiation method.
If specific gravity is know then it can be found out by pycnometer also.
Core cutter method and sand replacement method are useful in finding in-situ unit weights of soil {Moist unit weight or bulk unit weight}
Specific gravity can be found out by pycnometer and indirectly by shrinkage limit.
(NOTE-Degree of saturation at shrinkage limit is 1)
For organic soils specific gravity ranges in 1.2-1.4
And for inorganic soils it is,
2.65-2.80{ex. Sand}
Sedimentation analysis consist of pipette analysis and hydrometer method
There are "3" corrections in hydrometer method.
Meniscus correction(+ve)
Deflocculating agent correction(-ve)
Temp. Correction.
+ve........ T>27ยฐC
-ve..........T<27ยฐC
Well graded soils have a greater compaction property .
Poorly garaded or uniformly graded consist of same grain size hence voids are there.
A special case of poorly graded soil is the one in which particles are either in excess or deficient called as gap graded soils! (Also called skip graded)
If D10=150 micron, it means 10% particles are finer than 150 micron. . .
Note that D10 is called effective particle size.
D50-Average size
D100- denotes the size of largest particle in the soil.
For well graded soils 1<Cc<3
For well graded gravels Cu>4
For Well Graded sands Cu>6
For poorly graded soils Cu=1
#Trick?????
G for gavaskar, S for sachin
Gavaskar four(เคเฅเคเคพ) Marto ๐
Sachin six marto๐
In casagrandes test to find liquid limit water content is found out corresponding to 25 no. Of blows
Plasticity index of sands is zero.
Toughness index is (plasticity index/flow index). . .. (#MMRDA 2015)
Sensitivity is always greater than unity and is directly proportional to thixotrophy.
Soil activity was explained by skempton.
Soil activity denotes swelling potential of soil.
@macedhule
Out of various unit weights of soils, unit weight of solids is maximum while submerged unit weight is minimum
( #Generaly submerged unit weight is only 50% of saturated weight--------- this point is related to bearing capacity---when water table rises to ground surface unit weight of water falls to 50% hence bearing capacity under submergence condition is reduced by 50%)
Plasticity and activity of montmorilonite is maximum.
Bentoninte is purest form of clay which consist of 98% clay.
Bentonite is also called drilling mud which is used as a lubricant.
@macedhule
As compared to normal soils expansive soils have
1. More liquid limit
2. Less plastic limit
3.less shrinkage limit
4.more volumetric shrinkage
5. More plasticity index( from pt. 1 & pt 2)
Clay is finer than 0.002 mm and is flacky in shape(#TRANSCO dec 2016)
@macedhule
Silt is finer than 0.075 mm and coarser than 0.002 mm
Boulders are greater than 300mm
Gravel size is greater than 4.75mm and smaller than 80mm
As per IS 1498:1970๐
coarse grained soils are classified into 8 groups while fine grained soils are classified into 10 groups
Thus there are total 18 groups
Eg.
GS would be sandy gravel
Gp - poorly graded gravel
GW- well graded gravel etc
@macedhule
๐1
If D10=150 micron, it means 10% particles are finer than 150 micron. . .
Note that D10 is called effective particle size.
D50-Average size
D100- denotes the size of largest particle in the soil.
For well graded soils 1<Cc<3
For well graded gravels Cu>4
For Well Graded sands Cu>6
For poorly graded soils Cu=1
#Trick?????
G for gavaskar, S for sachin
Gavaskar four(เคเฅเคเคพ) Marto ๐
Sachin six marto๐
In casagrandes test to find liquid limit water content is found out corresponding to 25 no. Of blows
Plasticity index of sands is zero.
Toughness index is (plasticity index/flow index). . .. (#MMRDA 2015)
Sensitivity is always greater than unity and is directly proportional to thixotrophy.
Soil activity was explained by skempton.
Soil activity denotes swelling potential of soil.
@MACEDHULE
Out of various unit weights of soils, unit weight of solids is maximum while submerged unit weight is minimum
( #Generaly submerged unit weight is only 50% of saturated weight--------- this point is related to bearing capacity---when water table rises to ground surface unit weight of water falls to 50% hence bearing capacity under submergence condition is reduced by 50%)
Plasticity and activity of montmorilonite is maximum.
Bentoninte is purest form of clay which consist of 98% clay.
Bentonite is also called drilling mud which is used as a lubricant.
As compared to normal soils expansive soils have
1. More liquid limit
2. Less plastic limit
3.less shrinkage limit
4.more volumetric shrinkage
5. More plasticity index( from pt. 1 & pt 2)
Clay is finer than 0.002 mm and is flacky in shape(#TRANSCO dec 2016)
Silt is finer than 0.075 mm and coarser than 0.002 mm
Boulders are greater than 300mm
Gravel size is greater than 4.75mm and smaller than 80mm
As per IS 1498:1970๐
coarse grained soils are classified into 8 groups while fine grained soils are classified into 10 groups
Thus there are total 18 groups
Eg.
GS would be sandy gravel
Gp - poorly graded gravel
GW- well graded gravel etc
#Markourwords 11
strength of Materials. . .
๐คStress is internal resistance while Pressure is on account of external loading.
๐Bodies develop stress
Fluid exherts pressure
๐บModulus of elasticity shows resistance to deformation
๐ฝSlope of stress strain curve found out at origin is called modulus of elasticity
๐Stress is directly proportional to strain within proportional limit.
This is called Hookes law.
โ Analysis based upon Hookes lay is called linear analysis and the design method is called Working stress method.
@MACEDHULE
Modulus of elasticity & poissons ratio, both are same in tension and compression.
๐ปHence for all grades of steel modulus of elasticity is same.
๐ฎAs per IS 456:2000 modulus of elasticity is 200 KN/mmยฒ
๐Stress, strain and moment pf intertia are all tensor quantities.
(Scalars are magnitude dependent, vectors are magnitude and direction dependent, Tensors are defined by axes and planes)
๐ฎThere are 9 stress components in a 3d stress system
3 normal stress components
6 shear stress components
๐ฒHowever as per law of complimentary shear, there are only 3 shear components.
(Law of complimentary shear states that shear components at right angles are same in magnitude)
๐Stress calculated on the basis of original area is called engineering stress/nominal stress.
๐ฅบStress calculated on the basis of instantaneous area(area at any time of loading) is called true stress/actual stress.
๐In tension true stress is greater than engg. Stress.
In compression true stress is less than engg. Stress.
๐ductile materials are characterised by large post elastic strain (plastic strain)
๐Hence wires can be drawn from ductiles materials only.
๐Total strain energy stored in a material upto elastic limit is simply elastic strain energy which is recoverable.
Total elastic strain energy is called resilience.
Spring is a resilient material.
Note that D10 is called effective particle size.
D50-Average size
D100- denotes the size of largest particle in the soil.
For well graded soils 1<Cc<3
For well graded gravels Cu>4
For Well Graded sands Cu>6
For poorly graded soils Cu=1
#Trick?????
G for gavaskar, S for sachin
Gavaskar four(เคเฅเคเคพ) Marto ๐
Sachin six marto๐
In casagrandes test to find liquid limit water content is found out corresponding to 25 no. Of blows
Plasticity index of sands is zero.
Toughness index is (plasticity index/flow index). . .. (#MMRDA 2015)
Sensitivity is always greater than unity and is directly proportional to thixotrophy.
Soil activity was explained by skempton.
Soil activity denotes swelling potential of soil.
@MACEDHULE
Out of various unit weights of soils, unit weight of solids is maximum while submerged unit weight is minimum
( #Generaly submerged unit weight is only 50% of saturated weight--------- this point is related to bearing capacity---when water table rises to ground surface unit weight of water falls to 50% hence bearing capacity under submergence condition is reduced by 50%)
Plasticity and activity of montmorilonite is maximum.
Bentoninte is purest form of clay which consist of 98% clay.
Bentonite is also called drilling mud which is used as a lubricant.
As compared to normal soils expansive soils have
1. More liquid limit
2. Less plastic limit
3.less shrinkage limit
4.more volumetric shrinkage
5. More plasticity index( from pt. 1 & pt 2)
Clay is finer than 0.002 mm and is flacky in shape(#TRANSCO dec 2016)
Silt is finer than 0.075 mm and coarser than 0.002 mm
Boulders are greater than 300mm
Gravel size is greater than 4.75mm and smaller than 80mm
As per IS 1498:1970๐
coarse grained soils are classified into 8 groups while fine grained soils are classified into 10 groups
Thus there are total 18 groups
Eg.
GS would be sandy gravel
Gp - poorly graded gravel
GW- well graded gravel etc
#Markourwords 11
strength of Materials. . .
๐คStress is internal resistance while Pressure is on account of external loading.
๐Bodies develop stress
Fluid exherts pressure
๐บModulus of elasticity shows resistance to deformation
๐ฝSlope of stress strain curve found out at origin is called modulus of elasticity
๐Stress is directly proportional to strain within proportional limit.
This is called Hookes law.
โ Analysis based upon Hookes lay is called linear analysis and the design method is called Working stress method.
@MACEDHULE
Modulus of elasticity & poissons ratio, both are same in tension and compression.
๐ปHence for all grades of steel modulus of elasticity is same.
๐ฎAs per IS 456:2000 modulus of elasticity is 200 KN/mmยฒ
๐Stress, strain and moment pf intertia are all tensor quantities.
(Scalars are magnitude dependent, vectors are magnitude and direction dependent, Tensors are defined by axes and planes)
๐ฎThere are 9 stress components in a 3d stress system
3 normal stress components
6 shear stress components
๐ฒHowever as per law of complimentary shear, there are only 3 shear components.
(Law of complimentary shear states that shear components at right angles are same in magnitude)
๐Stress calculated on the basis of original area is called engineering stress/nominal stress.
๐ฅบStress calculated on the basis of instantaneous area(area at any time of loading) is called true stress/actual stress.
๐In tension true stress is greater than engg. Stress.
In compression true stress is less than engg. Stress.
๐ductile materials are characterised by large post elastic strain (plastic strain)
๐Hence wires can be drawn from ductiles materials only.
๐Total strain energy stored in a material upto elastic limit is simply elastic strain energy which is recoverable.
Total elastic strain energy is called resilience.
Spring is a resilient material.