👉Short Notes About Footing
🏷FOOTINGS
➡️Footings are mainly used to transmit the load from super structure to the underlying soil (substructure)
🚧1. Isolated footings
▶️Isolated footings are provided under each column and may be rectangular, square or circular in plan.
▶️It’s footing may be flat or tapered
🚧2. Combined Footings
▶️Combined footing supports two or sometimes three columns in a row.
▶️Combined footing is used when property lines, equipment locations, column spacing or other considerations limit the footing clearance at the column location Combined footing can be rectangular in shape if both the columns carry equal loads or Trapezoidal if there is a space limitation and they carry unequal loads.
🚧3. Strap footings
▶️Consists of two individual footings connected by a beam called strap.
▶️It’s used where the distance between the columns is so great that a trapezoidal combined footing becomes quite narrow, with resulting high bending moments.
▶️The strap beam doesn’t remain in contact with soil so a strap doesn’t transfer any pressure to the soil.
🚧4. Mat or raft foundation
▶️Is Combined footing that covers the entire area beneath a structure and supports all the columns.
▶️Foundation Engineers often considers mats when dealing with any one of the following conditions
*⃣The structural loads are so high or the soil conditions so poor that spread footings would be exceptionally large
*⃣The soil is very erratic and prone to excessive differential settlement.
*⃣The structural loads are erratic and thus increase the likelihood of excessive differential settlement.
🚧5. Pile foundations
▶️Pile foundations are the part of a structure used to carry and transfer the load of the structure to the bearing ground located at some depth below ground surface.
▶️The main components of the foundation are the pile cap and the piles.
▶️Piles are relatively long and slender members used to transmit foundation loads through soil strata of low bearing capacity to deeper soil or rock having a higher bearing capacity.
#ConstructionNotes
#Footing
@etconp
🏷FOOTINGS
➡️Footings are mainly used to transmit the load from super structure to the underlying soil (substructure)
🚧1. Isolated footings
▶️Isolated footings are provided under each column and may be rectangular, square or circular in plan.
▶️It’s footing may be flat or tapered
🚧2. Combined Footings
▶️Combined footing supports two or sometimes three columns in a row.
▶️Combined footing is used when property lines, equipment locations, column spacing or other considerations limit the footing clearance at the column location Combined footing can be rectangular in shape if both the columns carry equal loads or Trapezoidal if there is a space limitation and they carry unequal loads.
🚧3. Strap footings
▶️Consists of two individual footings connected by a beam called strap.
▶️It’s used where the distance between the columns is so great that a trapezoidal combined footing becomes quite narrow, with resulting high bending moments.
▶️The strap beam doesn’t remain in contact with soil so a strap doesn’t transfer any pressure to the soil.
🚧4. Mat or raft foundation
▶️Is Combined footing that covers the entire area beneath a structure and supports all the columns.
▶️Foundation Engineers often considers mats when dealing with any one of the following conditions
*⃣The structural loads are so high or the soil conditions so poor that spread footings would be exceptionally large
*⃣The soil is very erratic and prone to excessive differential settlement.
*⃣The structural loads are erratic and thus increase the likelihood of excessive differential settlement.
🚧5. Pile foundations
▶️Pile foundations are the part of a structure used to carry and transfer the load of the structure to the bearing ground located at some depth below ground surface.
▶️The main components of the foundation are the pile cap and the piles.
▶️Piles are relatively long and slender members used to transmit foundation loads through soil strata of low bearing capacity to deeper soil or rock having a higher bearing capacity.
#ConstructionNotes
#Footing
@etconp
👉Important concepts
🔹Which type of cement is used for underground concrete structures ?
➡️SRC (Sulphate Resisting Cement)
▶️The use of SRC is recommended for following applications:
*⃣Foundations, piles, basements and underground structures.
*⃣Sewage and Water treatment plants.
🔹What Is Roller Support
➡️Roller supports only resists perpendicular forces and they cannot resist parallel or horizontal forces & moment.
➡️It means the roller support will move freely along the surface without resisting horizontal force.
🔹What is the Concrete Temperature?
➡️Concrete temperature should not be more than 33°C & not less than 15°C in cold weather But the pumping temperature of concrete in hot weather should be 26°C.
🔹Do you know SPT ?
➡️SPT (Standard Penetration Test) is carried out to know the bearing capacity of soil.
➡️This is usually done on the foundation of bridges and the huge buildings.
#ConstructionNotes
@etconp
🔹Which type of cement is used for underground concrete structures ?
➡️SRC (Sulphate Resisting Cement)
▶️The use of SRC is recommended for following applications:
*⃣Foundations, piles, basements and underground structures.
*⃣Sewage and Water treatment plants.
🔹What Is Roller Support
➡️Roller supports only resists perpendicular forces and they cannot resist parallel or horizontal forces & moment.
➡️It means the roller support will move freely along the surface without resisting horizontal force.
🔹What is the Concrete Temperature?
➡️Concrete temperature should not be more than 33°C & not less than 15°C in cold weather But the pumping temperature of concrete in hot weather should be 26°C.
🔹Do you know SPT ?
➡️SPT (Standard Penetration Test) is carried out to know the bearing capacity of soil.
➡️This is usually done on the foundation of bridges and the huge buildings.
#ConstructionNotes
@etconp
👉Important Different Notes
🔹What is Fixed Supports
➡️Fixed supports are also known as rigid supports.
➡️Fixed supports are restrained against both rotation and translation so that they can resist any type of force or moment.
🔹Pinned / Hinged Support
➡️Pinned or hinged support can resist both vertical and horizontal forces but they cannot resist a moment.
➡️It means that hinged support is restrained against translation.
🔹What is Strip footing
➡️It is a component of shallow foundation which distributes the weight of a load bearing wall across the area of the ground.
➡️It is also known as a wall footing.
🔹What is Purpose of liquid limit test of soil
➡️Liquid limit can be determined to know shearing resistance of the soil.
🔹Difference between Earthen and Gravel Road
🚧Earthen Roads
➡️Earthen roads are lay with soil But, They are cheaper of all types of roads.
➡️Generally, This type of road is provided for less traffic areas and or for countryside areas.
➡️Good drainage system should be require which reflects good performance for longer period.
🚧Gravel Roads
➡️Gravel roads are also low quality roads but they are good when compare to earthen roads.
➡️Compacted mixture of gravel and earth is use as pavement material in this case.
#ConstructionNotes
@etconp
🔹What is Fixed Supports
➡️Fixed supports are also known as rigid supports.
➡️Fixed supports are restrained against both rotation and translation so that they can resist any type of force or moment.
🔹Pinned / Hinged Support
➡️Pinned or hinged support can resist both vertical and horizontal forces but they cannot resist a moment.
➡️It means that hinged support is restrained against translation.
🔹What is Strip footing
➡️It is a component of shallow foundation which distributes the weight of a load bearing wall across the area of the ground.
➡️It is also known as a wall footing.
🔹What is Purpose of liquid limit test of soil
➡️Liquid limit can be determined to know shearing resistance of the soil.
🔹Difference between Earthen and Gravel Road
🚧Earthen Roads
➡️Earthen roads are lay with soil But, They are cheaper of all types of roads.
➡️Generally, This type of road is provided for less traffic areas and or for countryside areas.
➡️Good drainage system should be require which reflects good performance for longer period.
🚧Gravel Roads
➡️Gravel roads are also low quality roads but they are good when compare to earthen roads.
➡️Compacted mixture of gravel and earth is use as pavement material in this case.
#ConstructionNotes
@etconp
👉Important concepts
🔹Compression failure in columns
➡️When columns are axially loaded, the concrete and steel will experience some stresses.
➡️When the loads are greater in amount compared to the cross sectional area of the column, the concrete and steel will reach the yield stress and failure will be starting without any later deformation.
➡️In this type of failure, the material fails itself, not the whole column.
➡️This type of failure mostly occurs in shorter and wider columns.
➡️To avoid this, the column should be made with sufficient cross-sectional area compared to the allowable stress.
🚧Function of stirrups in the column
➡️Stirrups are provided to handle the shear force and to hold the rebars in position.
#ConstructionNotes
@etconp
🔹Compression failure in columns
➡️When columns are axially loaded, the concrete and steel will experience some stresses.
➡️When the loads are greater in amount compared to the cross sectional area of the column, the concrete and steel will reach the yield stress and failure will be starting without any later deformation.
➡️In this type of failure, the material fails itself, not the whole column.
➡️This type of failure mostly occurs in shorter and wider columns.
➡️To avoid this, the column should be made with sufficient cross-sectional area compared to the allowable stress.
🚧Function of stirrups in the column
➡️Stirrups are provided to handle the shear force and to hold the rebars in position.
#ConstructionNotes
@etconp
👉Important Notes
🔸Important concepts in Irrigation Engineering.
🚧Duty :
➡️The term duty means the area of land that can be irrigated with unit volume of irrigation water. Duty represents the irrigating capacity of a unit.
🚧Delta:
➡️It is the total depth of the water required by a crop during the entire period the crop is in the field and is denoted by the symbol ∆.
🏷What Is Barrage Mean
➡️A barrage is a type of low-head, diversion dam which consists of a number of large gates that can be opened or closed to control the amount of water passing through.
➡️This allows the structure to regulate and stabilize river water elevation upstream for use in irrigation and other systems.
🔹Purpose of Barrage
*⃣1. To maintain pond level.
*⃣2. To raise the water level during low supplies. In case of higher floods, shutters are dropped down and overflow takes place while in case of gated weir, gates are raised during floods.
🏷What Are The Various Tests on Concrete with Apparatus
⏺1. Slump Cone Test
⏺2. Compressive Strength Test
⏺3. Water Absorption Test
⏺4. Water Permeability Test
⏺5. Compaction Factor Test
🏷What Is Contour map Mean
➡️A topographic map on which the shape of the land surface is shown by contour lines, the relative spacing of the lines indicating the relative slope of the surface.
🏷What Is Development length
➡️Development length is an extera length of steel, which transfer the load from one steel bar to other.
#ConstructionNotes
@etconp
🔸Important concepts in Irrigation Engineering.
🚧Duty :
➡️The term duty means the area of land that can be irrigated with unit volume of irrigation water. Duty represents the irrigating capacity of a unit.
🚧Delta:
➡️It is the total depth of the water required by a crop during the entire period the crop is in the field and is denoted by the symbol ∆.
🏷What Is Barrage Mean
➡️A barrage is a type of low-head, diversion dam which consists of a number of large gates that can be opened or closed to control the amount of water passing through.
➡️This allows the structure to regulate and stabilize river water elevation upstream for use in irrigation and other systems.
🔹Purpose of Barrage
*⃣1. To maintain pond level.
*⃣2. To raise the water level during low supplies. In case of higher floods, shutters are dropped down and overflow takes place while in case of gated weir, gates are raised during floods.
🏷What Are The Various Tests on Concrete with Apparatus
⏺1. Slump Cone Test
⏺2. Compressive Strength Test
⏺3. Water Absorption Test
⏺4. Water Permeability Test
⏺5. Compaction Factor Test
🏷What Is Contour map Mean
➡️A topographic map on which the shape of the land surface is shown by contour lines, the relative spacing of the lines indicating the relative slope of the surface.
🏷What Is Development length
➡️Development length is an extera length of steel, which transfer the load from one steel bar to other.
#ConstructionNotes
@etconp
👉Lets See About Structure Supports
🔹Fixed Supports
▶️Fixed supports are also known as rigid supports.
▶️Fixed supports are restrained against both rotation and translation so that they can resist any type of force or moment.
🔹Pinned / Hinged Support
▶️Pinned or hinged support can resist both vertical and horizontal forces but they cannot resist a moment.
▶️It means that hinged support is restrained against translation.
🔹Roller Support
▶️Roller supports only resists perpendicular forces and they cannot resist parallel or horizontal forces & moment.
▶️It means the roller support will move freely along the surface without resisting horizontal force.
#Structure
#ConstructionNotes
@etconp
🔹Fixed Supports
▶️Fixed supports are also known as rigid supports.
▶️Fixed supports are restrained against both rotation and translation so that they can resist any type of force or moment.
🔹Pinned / Hinged Support
▶️Pinned or hinged support can resist both vertical and horizontal forces but they cannot resist a moment.
▶️It means that hinged support is restrained against translation.
🔹Roller Support
▶️Roller supports only resists perpendicular forces and they cannot resist parallel or horizontal forces & moment.
▶️It means the roller support will move freely along the surface without resisting horizontal force.
#Structure
#ConstructionNotes
@etconp
📌Difference between working stress approach and limit state approach
🔸Working Stress Approach
➡️The service loads are used in the whole design and the strength of material is not utilized in the full extent.
➡️In this method of design, stresses acting on structural members are calculated based on elastic method and they are designed not to exceed certain allowable values.
➡️In fact, the whole structure during the life span may only experience loading stresses far below the ultimate state and that is the reason why this method is called working stress approach.
➡️Under such scenario, the most economical design can hardly be obtained by using working stress approach which is now commonly used in the design of temporary works.
🔸Limit State Approach
▶️For each material and load, a partial safety factor is assigned individually depending on the material properties and load properties.
▶️Therefore, each element of load and material properties is accurately assessed resulting in a more refined and accurate analysis of the structure.
▶️In this connection, the material strength can be utilized to its maximum value during its life span and loads can be assessed with reasonable probability of occurrence.
▶️Limit state approach is commonly used for the majority of reinforced concrete design because it ensures the utilization of material strength with the lowest construction cost input.
#ConstructionNotes
#Structure
@etconp
🔸Working Stress Approach
➡️The service loads are used in the whole design and the strength of material is not utilized in the full extent.
➡️In this method of design, stresses acting on structural members are calculated based on elastic method and they are designed not to exceed certain allowable values.
➡️In fact, the whole structure during the life span may only experience loading stresses far below the ultimate state and that is the reason why this method is called working stress approach.
➡️Under such scenario, the most economical design can hardly be obtained by using working stress approach which is now commonly used in the design of temporary works.
🔸Limit State Approach
▶️For each material and load, a partial safety factor is assigned individually depending on the material properties and load properties.
▶️Therefore, each element of load and material properties is accurately assessed resulting in a more refined and accurate analysis of the structure.
▶️In this connection, the material strength can be utilized to its maximum value during its life span and loads can be assessed with reasonable probability of occurrence.
▶️Limit state approach is commonly used for the majority of reinforced concrete design because it ensures the utilization of material strength with the lowest construction cost input.
#ConstructionNotes
#Structure
@etconp
👉HOW TO TAKE 90 DEGREE ANGLE FOR BUILDING LAYOUT
➡️How we can take the 90 degree angle in building layout so after reading this article you will be able to know how to take 90 degree angle during layout at site.
▶️In many projects many students can become the face of this problem that they are not able to take 90 angle for building or room layout at site and keep in your mind that we must take any corner of the building on 90 degree so after that our work will be fine from that.
▶️So the given formula which I am showing you now , this is the manual formula which you can do with the help of measurment tape.
🚧FORMULA TO TAKE 90 DEGREE
*⃣3 AND 4 = 5
▶️Here we have to take one side 3 meter or feet and 2nd side 4
▶️So the other side should be measure 5 meter than it will give us 90 degree angle.
🚧*NOTE:* the above formula we can not use for level machine or any other electronic machine it just used for manual work and we can complete our lay-outing with 90 degree angle with the help of measurement tape.
#ConstructionNotes
@etconp
➡️How we can take the 90 degree angle in building layout so after reading this article you will be able to know how to take 90 degree angle during layout at site.
▶️In many projects many students can become the face of this problem that they are not able to take 90 angle for building or room layout at site and keep in your mind that we must take any corner of the building on 90 degree so after that our work will be fine from that.
▶️So the given formula which I am showing you now , this is the manual formula which you can do with the help of measurment tape.
🚧FORMULA TO TAKE 90 DEGREE
*⃣3 AND 4 = 5
▶️Here we have to take one side 3 meter or feet and 2nd side 4
▶️So the other side should be measure 5 meter than it will give us 90 degree angle.
🚧*NOTE:* the above formula we can not use for level machine or any other electronic machine it just used for manual work and we can complete our lay-outing with 90 degree angle with the help of measurement tape.
#ConstructionNotes
@etconp
👉What are the advantages of piers constructed monolithically with the bridge deck over usage of bearings?
➡️Basically, piers constructed monolithically with the bridge deck are advantageous in the
following ways:
🚧(i) Movement of the bridge deck is achieved by the bending deformation of long andslender piers.
▶️In this way, it saves the construction cost of bearings by using monolithic construction between bridge deck and piers.
▶️Moreover, it is not necessary to spend extra effort to design for drainage details and access for bearing
replacement.
▶️On the other hand, in maintenance aspect substantial cost and time
savings could be obtained by using monolithic construction instead of using bearings as bridge articulation.
🚧(ii) Monolithic construction possesses the shortest effective Euler buckling length for piers because they are fixed supports at the interface between bridge deck and piers.
⚡️Note: Monolithic construction means that piers are connected to bridge decks without any joints and bearings.
#ConstructionNotes
@etconp
➡️Basically, piers constructed monolithically with the bridge deck are advantageous in the
following ways:
🚧(i) Movement of the bridge deck is achieved by the bending deformation of long andslender piers.
▶️In this way, it saves the construction cost of bearings by using monolithic construction between bridge deck and piers.
▶️Moreover, it is not necessary to spend extra effort to design for drainage details and access for bearing
replacement.
▶️On the other hand, in maintenance aspect substantial cost and time
savings could be obtained by using monolithic construction instead of using bearings as bridge articulation.
🚧(ii) Monolithic construction possesses the shortest effective Euler buckling length for piers because they are fixed supports at the interface between bridge deck and piers.
⚡️Note: Monolithic construction means that piers are connected to bridge decks without any joints and bearings.
#ConstructionNotes
@etconp
👉Some important facts
🚧1. Weight of one cement bag = 50 kg
🚧2. Minimum thickness of slab = 125 mm
🚧3. Minimum lintel thickness =15 cm
🚧4. Minimum diameter of bars used in slab= 8 mm
🚧5. Minimum diameter of bars Used in column = 12 mm
🚧6. Maximum diameter of bars in slab= 1/8x(thickness of slab )
🚧7. Maximum chair spacing = 1m
🚧8. Initial setting time of cement = 30 min
🚧9. Final setting time = 10 hrs ( 600 minutes )
🚧10. DPR = Detailed Project Report
🚧11. Unit weight
▶RCC = 25 KN/ m3
▶PCC = 24 KN/ m3
▶Steel = 7850 kg/ m3
🚧12. Minimum number of bars For square column or rectangular = 4 bars & For circular column = 6 bars
🚧13. Weight of steel = D2/162.2 kg/m.
🚧14. Slope of staircase = 25° -40° from horizontal.
🚧15. Size of concrete testing cube= (150x150x150)mm.
🚧16. Concrete cube is filled in 3 layers.
🚧17. Slump cone is filled in 4 layers.
🚧18. Cement should be used within three months of manufacturing.
🚧19. Minimum thickness of shear wall = 150 mm.
🚧20. Maximum thickness of shear wall = 400 mm.
🚧21. Universal testing machine is used for compression Test of concrete and tensile test of steel reinforcement.
🚧22. Minimum curing period of normal weather conditions is = 7 days
🚧23. Minimum curing period of dry and hot weather conditions is = 10 days
🚧24. Minimum percentage of steel in column = 0.8% of the cross section.
🚧25. Normal cover
➡️Footing = 50 mm
➡️Column = 25 mm
➡️Slab = 15 mm
➡️Beam = 25 mm
🚧26. Number Of Clear span stirrups in beam = Center to Center length /Total Length +1
🚧27. RCC is affected by water because of the corrosion of reinforcement bars.
🚧28. PCC is not affected by the water
🚧29. Maximum free fall of concrete = 1.5 m
🚧30. Air voids left in concrete is called as Honey Combing.
🚧31. The transverse reinforcement of column are called TIES.
🚧32. The transverse reinforcement in beams are called STIRRUPS.
🚧33. Cement ingredients are Burnt @ 1400°C temperature
🚧34. Short columns fail in Crushing.
🚧35. Long columns fail in Buckling.
🚧36. Intermediate columns can fail both in Buckling and Crushing.
🚧37. Strength of reinforcement shouldn't be less than 15 % of its designated strength.
🚧38. Compressive strength of bricks
▶️1st class bricks = 105 kg/cm2.
▶️2nd class bricks = 70 kg/cm2.
▶️3rd class bricks = 35 kg/cm2.
🚧39. PH value of water used concrete should not be less than 6.
🚧40. Riser = (150 - 200) mm.
🚧41. Tread = (250 - 300) mm.
🚧42. Height of parapet wall should be= 1m.
🚧43. TMT - Thermo mechanically treated bars.
🚧44. TMX - Thermax powered bars
🚧45. SDB - Super ductile bars.
#ConstructionNotes
@etconp
🚧1. Weight of one cement bag = 50 kg
🚧2. Minimum thickness of slab = 125 mm
🚧3. Minimum lintel thickness =15 cm
🚧4. Minimum diameter of bars used in slab= 8 mm
🚧5. Minimum diameter of bars Used in column = 12 mm
🚧6. Maximum diameter of bars in slab= 1/8x(thickness of slab )
🚧7. Maximum chair spacing = 1m
🚧8. Initial setting time of cement = 30 min
🚧9. Final setting time = 10 hrs ( 600 minutes )
🚧10. DPR = Detailed Project Report
🚧11. Unit weight
▶RCC = 25 KN/ m3
▶PCC = 24 KN/ m3
▶Steel = 7850 kg/ m3
🚧12. Minimum number of bars For square column or rectangular = 4 bars & For circular column = 6 bars
🚧13. Weight of steel = D2/162.2 kg/m.
🚧14. Slope of staircase = 25° -40° from horizontal.
🚧15. Size of concrete testing cube= (150x150x150)mm.
🚧16. Concrete cube is filled in 3 layers.
🚧17. Slump cone is filled in 4 layers.
🚧18. Cement should be used within three months of manufacturing.
🚧19. Minimum thickness of shear wall = 150 mm.
🚧20. Maximum thickness of shear wall = 400 mm.
🚧21. Universal testing machine is used for compression Test of concrete and tensile test of steel reinforcement.
🚧22. Minimum curing period of normal weather conditions is = 7 days
🚧23. Minimum curing period of dry and hot weather conditions is = 10 days
🚧24. Minimum percentage of steel in column = 0.8% of the cross section.
🚧25. Normal cover
➡️Footing = 50 mm
➡️Column = 25 mm
➡️Slab = 15 mm
➡️Beam = 25 mm
🚧26. Number Of Clear span stirrups in beam = Center to Center length /Total Length +1
🚧27. RCC is affected by water because of the corrosion of reinforcement bars.
🚧28. PCC is not affected by the water
🚧29. Maximum free fall of concrete = 1.5 m
🚧30. Air voids left in concrete is called as Honey Combing.
🚧31. The transverse reinforcement of column are called TIES.
🚧32. The transverse reinforcement in beams are called STIRRUPS.
🚧33. Cement ingredients are Burnt @ 1400°C temperature
🚧34. Short columns fail in Crushing.
🚧35. Long columns fail in Buckling.
🚧36. Intermediate columns can fail both in Buckling and Crushing.
🚧37. Strength of reinforcement shouldn't be less than 15 % of its designated strength.
🚧38. Compressive strength of bricks
▶️1st class bricks = 105 kg/cm2.
▶️2nd class bricks = 70 kg/cm2.
▶️3rd class bricks = 35 kg/cm2.
🚧39. PH value of water used concrete should not be less than 6.
🚧40. Riser = (150 - 200) mm.
🚧41. Tread = (250 - 300) mm.
🚧42. Height of parapet wall should be= 1m.
🚧43. TMT - Thermo mechanically treated bars.
🚧44. TMX - Thermax powered bars
🚧45. SDB - Super ductile bars.
#ConstructionNotes
@etconp
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