SAFE BEARING CAPACITY OF SOIL

 SBC OF SOIL

The safe bearing capacity of soil is defined as the maximum load per unit area that the soil can bear without any displacement or settlement. This is measured in terms of kilograms per square centimeter. If the load exceeds this mark, the soil will start to displace or break. This will lead to structure settlement, which can end up in destructive results.

Formula:
Safe bearing capacity of soil = (ultimate bearing capacity)/(Cross-section area x Factor of safety)

          *The ultimate bearing capacity of the soil - the point at which the soil starts to displace under load. Any soil can take up to a certain amount of load only, after which it starts to settle or displace.

           *The cross-section area is the area of soil on site on which the tests are being performed. It can be a square meter in general practice.

          *The factor of safety indicates how safe the soil capacity results must be before considering a certain type of construction. Naturally, it depends upon the type of building being constructed. It is kept at 2 for general civil constructions and 3 for high-rise or heavy constructions.

Testing Procedures for Soil Bearing Capacity: 

Drop Weight Method is the easiest and it is a tried and tested true test.

Drop Weight Test:

1. Dig up a pit down to the foundation depth.

2. Find a heavy perfectly cube-shaped object. Stone blocks work best. Measure its precise weight.

3. Lift the cube up to a predetermined height directly over the pit. This must be precise as well.

4. Drop the cube in the pit, and then carefully lift it out without disturbing the impression made by the block.

5. Measure the depth of the impression made by the block.

6. Repeat the above process several times and take the average value.

Example:

Weight of the block: 1.2 kg
Height of drop: 120cm
Depth of impression: 1.6cm
Cross section: 20 sq.cm.
Factor of safety: 2

Therefore, ultimate bearing capacity = (1.2 x 120)/1.6 = 90

And, safe bearing capacity of soil = 90/(20 x 2) = 2.25 kg/cm².

Safe Bearing Capacity (SBC) values for different types soils: 

(The values below are probable only and to use for preliminary design of structures.)

Soft,wet or muddy clay: 0.5 kg/cm²
Black cotton soil: 1.5 kg/cm²
Loose gravel: 2.5 kg/cm²
Compacted clay: 4.5 kg/cm²
Soft rocks: 4.5 kg/cm²
Compacted gravel: 4.5 kg/cm²
Hard rocks: 33.0 kg/cm²
Coarse sand: 4.4 kg/cm²
Medium sand: 2.45 kg/cm²
Fine sand: 4.45 kg/cm²

COMPLETE GUIDE TO GROUTING

 GROUTING

Grouting is generally a mixture of cement, sand and water or chemical used to fill gaps or used as reinforcement in existing structures.

The purpose of grouting can be either to strengthen a formation or to reduce water flow through it. It is also used to correct faults in concrete and masonry structures

Applications of grouting

1.   For grouting machine foundation, base plate, bearing and column joints in precast construction

2.   It is used for filling voids, gaps and cavities in the concrete

3.   Grouting is done for filling the voids between the rock face and lining in tunnel work

4.   It is used for fixing tendons post-tensioned in prestressed concrete construction.

5.   It is used for repairing pavement and ground below the foundation.

6.   It is used for repairing cracks in concrete and defects in masonry

 7.  Also, for fixing ground anchors for concrete pile wall.

The process of grouting consists of filling pores or cavities in soil or rock with a liquid form material to decrease the permeability and improve the shear strength by increasing the cohesion when it is set. Cement base grout mixes are commonly used for gravely layers or fissure rock treatment.

TYPES OF GROUTS

1. Cementitious Grouts

Cementitious grout is used to create a solid bearing surface between structural baseplates and base foundations. It enables even dispersal of the load into the existing concrete slab. Cementitious grout is suitable for a range of different bedding and fixing applications.

a) Ordinary Portland cement grouting

It is commonly used for repairing concrete cracks. Since they have the particulate size of 15 microns they can help in filing the wider cracks.

b) Micro-fine cement grouting

Finely ground slag, fine fly ash, or Portland cement are mixed with water to allow penetration into the fine cracks. They have the particulate size in the range of 6 to 10 microns.

 c) Ultra-fine cement grouting

This grout is used for sealing the very fine hairline like cracks and have the particulate size of 3 to 5 microns. They are used for stabilizing waste plumes.

d) Sanded grout 

Sanded grout is most commonly used for ceramic tile, stone and any tile with a grout joint or larger. It is composed of Portland cement, sand and other additives, it is mixed with water and troweled into the grout joint, where it takes approximately 24 hours to dry.

For joints 3.175 to 9.525 mm (1/8 to 3/8”) wide, fine sanded grout

For joints 9.525 to 12.7 mm (3/8 to 1/2”) wide, Coarse sand will be used.

e) Unsanded grout 

Unsanded grout, commonly called “wall grout,” is essentially sanded grout without the sand. It is used on ceramic tile and polished marble with grout joints smaller than 1/8 inch.

f) Latex modified grout

Sanded grouts may be formulated with a latex polymer additive, either included in the dry mix or added in as the grout is mixed with water.

2. Chemical grouts

Chemical grouts are an emulsion of water and liquid resin. Chemical grouting requires injection of specially formulated chemical grouts into finer cracks that cannot be possible by cement grouts. Some of the popular ones are epoxy, acrylic and furan resin grouts.

a) Epoxy grout 

Epoxy grout is strong and durable. It is highly resistant to stains, cracks, chemicals, harsh weather conditions, and climate changes. These characteristics make epoxy grout the only way to go if you’re looking for the most durable, efficient way to do tile work.

b) Acrylic grout 

With acrylic grout is that you don’t have to cover the entire work surface. You can just apply it in the joints between the tiles. The silicone additive, which comes premixed with Portland cement grout, aid¬s in greater adhesion. Because of its stability in freezes and thaws, it can be used outdoors, making it perfect for deck or garage projects.

c) Furan grout 

Furan grout is similar to epoxies, but are composed of polymers of furfuryl alcohol, which are highly resistant to chemical action. Furans are two-component systems that contain a furan resin and a filler powder with an acid catalyst. It is the acid catalyst that causes the furan resins to cure, forming a thermosetting resin that has unsurpassed chemical, physical and thermal-resistance.

Furan grout is commonly used to grout brick pavers and quarry tile and it is also recommended in areas exposed to chemicals and grease. The tile surfaces may be smooth, non-skid, or abrasive, depending on the intended use for the floor. The tile or brick surfaces must receive a wax coating to protect them from staining prior to the installation of furan

3. Polyester grouts

For decades, grouting has been the most popular soil stabilization method. Some additives, as well as cement and polymeric materials, are also widely used as grout mixtures in order to lower costs and achieve the best engineering properties with early strength gain. Unconfined compression and dynamic tests of grouted granular soils were conducted with different mixtures to evaluate the feasibility of using polyester, red mud and micronized clay as grouting materials. This type of grouts advances with increasing additive percentages and curing time. Polyester grout is used for anchoring to impart strength to foundations that must be achieved in limited available space.

4. Non-shrink grout

Non shrinking grout

Non-shrink grouts are hydraulic cement grout that, when hardened under stipulated test conditions, does not shrink, so its final volume is greater than or equal to the original installed volume. It is often used as a transfer medium between load-bearing members. This grout often sets rapidly. It is a pre-mix product that needs only to be mixed with [water] which includes ingredients to compensate against cement stone shrinkage

G1 Grout

It is mainly used for steel structures, small pumps, ships, towers and all other non-vibration machinery. It should be cementitious, nonshrinkable and free flow with compressive strength equal or greater than the foundation’s concrete, but not less than 30n/mm2 in 7 days and 40n/mm2 in 28 days.

G2 Grout

It is generally used for prefabricated concrete structures, compressors, heavy equipment subjected to vibration and for massive structure’s column bearing plates. Minimum compressive strength should be 50N/mm2 in 7 days and 60n/mm2 in 28 days. The grout’s flexibile strength should not exceed 9n/mm2 in 28 days.

It should be cementitious, nonshrinkable high strength grout.

Mixing of grout

Mixing of grouting powder with water can be done mechanically using an electric drill

For Flowable grouting – Water:Powder = 0.14 to 0.16 by weight (4.2 to 4.8 litres water for 30 Kg bag)

For Pourable grouting – Water:Powder = 0.12 to 0.14 by weight (3.6 to 4.2 litres water for 30 Kg bag)

The minimum mixing time is 3 minutes

5. Bituminous grouting

In this method, hot bitumen is used as a grouting material. Hot bitumen is employed associated with solidify based suspension grout. this is often never really grout from spreading and to create the mechanical quality of the finished result.

A hard-oxidized environment friendly, having a high solidification point is used for grouting.

Process of bituminous grouting

Firstly, the bitumen is heated up to 200 degrees Celsius. At this time the grout has a dynamic viscosity in the range 15 to 100 cp.

Unlike another grouting, the hot bitumen’s curing is thermally driven. This hot bitumen turns from its fluid state to a highly viscous elastoplastic state, when it is injected into medium saturated water. Finally, when this is injected the pass is plugged.

6. Resin grouting

In traditional resin grout, it is the composition of epoxy resin mixed with the filler. But new type of water-based resin has been recently developed that is better than the traditional ones.

It is also known as penetration grouting and is the most conventional grouting for use. This grouting method is used in non-cohesive soil, sand, and other porous media for filling cracks and joints.

It is injected inside the porous medium without disturbing its original structure. It is commonly used in soil and rock deposits to change its geotechnical properties.

There are two types of Permeation grouting injecting system:

• Circulating grout system

• Direct grout system

Types of Grouting based on the the Process

1) Compaction grouting

 Compaction grouting is done to strengthen the subsurface or surface of the permeable soil to reduce the voids and sinkholes.

It is driven to the depth through the drill. Cement, sand, fly ash, and water is then placed from bottom to top according to the pressure criteria. After each step, the drill is lifted up until it is fully taken out. This grouting is commonly called low mobility grouting

2) Bentonite grouting

Bentonite is made up of the clay having thixotropic properties that is a highly water-resistant gel which forms the permanent barrier to water flow when mixed with additives.

This method is used in the soil particles that cannot accept the cement grouting. This is commonly used for plugging old wells.

It is composed of 50 pounds of powdered bentonite to 34 gallons of water in which 50 pounds of washed sand is added.

3) Fracture grouting

In this method, grout uses the low viscosity grouts that splits by hydraulic fracture under the high pressure and enters into the cracks by creating the lenses. It is also known as compensation grouting and is commonly used for structural releveling.

Procedure of hydraulic fracture:

In this method, a hydraulically pressurized liquid composed of water, sand, and chemical mixture is used to fracture the rock. Artificial cracks are provided with pre-split holes. Then, the grout is passed down the holes.

The casing is inserted to the fracture section and grouted. A pressurized fluid carrier is inserted into the opening casing and spread throughout fractures. The casing remains open after fracturing.

4) Jet grouting in construction

This is a process of creating soil concrete column or jet grouted column using high-pressure jet through the nozzle in a borehole.

The specially designed drill stem and the monitor are raised and rotated at slow, smooth, and constant speed cutting the soil with water or/and air at high pressure to create the soil concrete column. The end product is then cemented round column. This grout is effective for almost soil.

Procedure of jet grouting:

1. Initially, the hole is drilled in the required place and depth.

2. The drill is done until a weak subsoil exists. It may be up to 10 to 20 cm.

3. Then, equipment is placed in the hole to conduct an injection process that consists of a jet grouting string of almost 7 to 10 cm.

4. The string consists of a nozzle to have an injection on high velocity, having a diameter of 1 to 10mm.

5. Then, the string is raised and rotated to seal the whole column with soil and the fluid system. Now, the jetting starts. The string is raised when the fluid is injected. For every raising, there is rotation performed smoothly and constantly. This gives a perfectly refined grouting column.

Types of jet grouting system

1. Single

2. Double

3. Triple fluid system.

Application of jet grouting

• Horizontal barriers

• Groundwater control

• Tunneling

• Supporting excavation

• Underpinning

Jet grouting steps

Types of Grout for Ceramic Tile 

There are four basic types of grout:

• Unsanded Grout

• Finely Sanded Grout

• Quarry TypeGrout

• Epoxy Grout

1. Unsanded Grout

This is used for wall tiles where the grout joint is less than 1/8” wide.

2. Finely Sanded Grout

This is used for floor tiles where the joints are 1/8” to 3/8” wide.

3. Quarry Type Grout

• This is the same as finely sanded grout for ceramic tiles except that a coarser grade of sand is used.

• The quarry-type grout is used for joints that are 3/8” wide to 1/2” wide such as those used with Terracota / Saltillo tiles.

4. Epoxy Grout

• This consists of an epoxy resin and hardener.

• Epoxy grout for ceramic tile is highly resistant to stains and chemicals and has a tremendous bonding strength.

• It is ideal for countertops and other areas susceptible to stains.

IS code for grouting

A fundamental requirement of a grout is that it shall develop adequate gel strength after a control- Page 11 IS 14343 : 1996 lable interval of time. This should be determined by relevant test procedures.

Applications of Grouting

(Courtesy: sika.com)

KNOW ABOUT FSI / FAR

 KNOW ABOUT FSI / FAR

FSI    -   Floor Space Index

FAR   -  Floor Area Ratio

FSI and FAR are the same. However, Indians prefer to use the term FAR on FSI, whereas other countries use FSI more frequently. FSI and FAR both represent the calculation based on the ratio derived by dividing the Gross floor area with the total size of land on which the building is made.

The concept of FSI or FAR got introduced in America. It was introduced for the building control. Architects make their designs based on these important ratios. 

For Example,

Plot area is 1000 Sqm. Total area of building in all the floors is 1000 Sqm. Then, FSI is 1.0

FSI is based on the National Building Code (NBC). Floor space index varies from place to place under the rules and regulations imposed by the state or city’s Authority or Administration. 

How to apply the Floor Area Ratio in building a house?

For example, if the FSI/FAR is 1 and the total plot area is 2,000 sq.ft., then the maximum buildable area of the building must not be more than 2,000 sq.ft. FAR does not have many limitations on how many floors a building must have, except for the height and other limitations the municipal or development body holds in specific areas and zones. 

Therefore, one can construct a building with only two floors extending 1,000 sq.ft. or four floors with 500 sq.ft. each. FSI, however, prohibits public amenities such as common area, parking area, interior open space, pipes and basement completely used for parking. These areas are excluded while calculating FSI.

Illustration of Different FSI

                                        (BCR - Building Coverage Ratio)

Importance of FSI

• The Floor space index is imposed by the government as the restriction and it has its own benefit at the place where construction of buildings is increasing day by day.
• It maintains a balance between sustained, planned growth, and development is important.
• An average FSI value ensures the good development of the project.
• It maintains the ratio of open space to built space.
• FSI is the best option to reduce stress in the city.

From this concept of FSI,  Government has an idea of how to divide the land for what percentage of the city area must be dedicated to the park, what percent for the road, and how to divide the remaining into the different zones. This helps in a great way to keep the resources of the city on good terms with more greenery, lesser traffic, and a lot more other amenities. 

FSI regulates by the Directorate of Town and Country Planning (DTCP) department.

Permissible value of the Floor Space Index (FSI) 

The permissible value of the Floor Space Index (FSI) differs from place to place. It also depends on the type of building. The FSI ratio value of a particular area is easily seen in all the building bylaws for different cities and municipalities. Different cities or municipalities may have different bylaws and thereafter different FSI values.

Permissible FSI/FAR value depends on:

• Size of the plot

• Type of building (residential, commercial, institutional, worship, etc.)

• The width of the adjacent road

• Availability of power, water, sewer lines

Impact of FAR on land value

FAR has a significant impact on land value. Higher permissible FAR brings higher land value.

Premium FSI

If anyone needs to extend the allowable Floor Space Index, they have to pay a Premium fee to the government. To get this FSI, the adjacent road of the land must be 30 feet.

• 30 to 40 Ft Road Width – 20 % Premium FSI

• 40 to 60 Ft Road Width – 30 % Premium FSI

• More than 60 Ft Road Width – 40 % Premium FSI

If the land location of the building has 30 – 40 feet adjoining roadway, then you can avail the Premium FSI of 20% which means you can build 20% more than allowable FSI.

Which areas included in FSI / FAR ?

FAR covers the basic structure, walls, staircase or lobby space, but excludes the balcony or terrace. lift and lobby.

For commercial buildings: The government permits you to construct offices in basements. However, space will be added in the calculation of FAR practice in this case.

For group housing: The basement construction is permitted for parking, utilities, and services but these are not included in FAR

FSI in India’s top 10 cities

1. Delhi

As per the revised Delhi Master Plan 2021, uniform Floor Area Ratio (FAR) for both residential and commercial properties, permitting the regularisation of illegal construction. This means the FAR for 100 sq.m was earlier variable, varying from 1.8 to 2.25, but now it is approved to be a uniform 3.5 for 100 sq.m.

There is no FAR restriction on group housing projects while plots in the influence zones and Metro corridors are allowed a higher FSI. Redevelopment projects in Delhi are provided an FSI value of 4.

2. Mumbai

 The residential FSI for the island city has been raised to 3.0 and commercial to 5.0 from 1.3 for both. In the suburbs, the FSI for residential projects has been increased to 2.5 from 2.0 and for commercial it stands at 5.0 as against 2.5.

3. Kolkata

As per the New Town Kolkata Building Rules, 2009, the range of FSI for residential buildings in Kolkata is between 1.5 and 2.5. The limit is fixed depending on the land use, road width, density, etc.

Recently, Kolkata civic body has made certain changes to the Floor Area Ratio (FAR) to allow the property owners to add an extra floor. This means that they will now get 3,000 sq ft extra space for construction, which is equivalent to the construction of an additional floor.

The real estate projects in Kolkata which are being developed within one kilometer of any metro line/route/corridor will have the eligibility to have a 20% higher floor area as compared to the floor area that was allowed previously. Apartments facing roads with width ranging between 15-24 m can apply for added floor area ratio to the tune of 15%. In the case of road width exceeding 24 m, this can go up to 20%. The floor area ratio is the ratio of the gross floor space of a building to the plot size.

4. Chennai

The permissible limit for FSI in Chennai is 2.0 which is a raise by 0.5 and it comes with retrospective effect from October 1, 2018. Though the increase in FSI will not be applicable in ecologically sensitive areas such as Aquifer Recharge Area, Red Hills Catchment Area, and Coastal Regulation Zone.

Construction of residential homes/buildings in Chennai, under Chennai’s 2nd Master Plan 2026 conforms to the FSI limit of 1.5 for normal residential buildings and 2 for high rise buildings.

As per Coastal Regulation Zone (CZR) 2011 Notification, the Floor Space Index (FSI) or the Floor Area Ratio (FAR) had been halted. On the other hand, in CRZ 2019 Notification, the state government decided to de-freeze the FSI and permit for construction projects.

5. Ahmedabad

After the implementation of the new General Development Control Regulations (GDCR) regulation which permits property owners and builders to redevelop buildings that are 25-meter high with higher Floor Area Ratio (FAR) along the roads which are less than 18-meter wide.

FSI in the prime localities of Ahmedabad is 1.2 while it goes up to 1.8 for localities in the suburbs.

Under the new rules, property owners will be granted a Floor Space Index (FSI) of 1.8 after which, they will have the option to avail paid FSI of up to 2.9, enabling property owners to reconstruct their old homes.

6. Bengaluru

The proposed FSI ranges from 2 to 5, depending on the size of the plot and the road and seeks to encourage vertical growth and wider open spaces in the form of setback areas. With this, properties along the Metro, suburban and bus corridors will benefit from the new policy.

7. Hyderabad

Hyderabad has not put FSI limitations that have indirectly managed the property prices to rise. The local body administration and urban development (MA&UD) department is, however, taking into consideration the reintroduction of floor space index (FSI) rule for high-rise buildings in Telangana.

8. Gurgaon

Under the new rules, FAR for residential plots in Gurgaon of 75 sq.m will be 2.64 and for 251 sq m till more than 500 sq.m, it will be 2.40.

The rate of the increased FAR also varies from Rs 485 to Rs 8,070 per sq.m depending upon the potential of zones. Similarly, the ground coverage for up to 75 sq m till 250 sq.m residential houses has been kept at 66%, while for 251 sq.m till over 500 sq.m houses, the ground coverage is 60%.

9. Noida

To boost the housing sector in Noida and Greater Noida, the State government has provided additional floor area ratio (FAR) along the newly operational Aqua Metro line, connecting Sector 52 and Greater Noida. This means that the developers are now allowed to add more floors in their high rise structures. Gr Noida Industrial Development Authority (GNIDA) has hiked FAR within 500 meters of Noida- Gr Noida metro corridor, Aqua-Line from 3.5 to 4. This proposed hike will be applicable to ongoing and upcoming residential projects in the region.

For Noida and Greater Noida, the value of FSI is placed between 2.75 and 4, group housing projects are granted a FAR of 3.5. The industrial buildings are granted a maximum FAR of 1.5 while commercial buildings have a maximum FAR of 4, depending on building height and area coverage.

10. Pune

In March 2019, the state govt has announced the transit-oriented development policy in a 500-meter radius around the metro stations in Pune and fixed the maximum permissible floor space index (FSI) to 4. The FSI is up to 4 and depends on the size of the plot and the width of the road. The state government has also put a condition on the road width and plot size for getting 4 FSI.

IMPORTANT CIVIL TIPS TO REMEMBER

 IMPORTANT TIPS FOR CIVIL ENGINEERS

STEEL

• Theoretical weight of Steel - 7850 kg/ m³
• Weight of reinforcement bars - D² / 162 Kg/m   (D in mm)
• Weight of reinforcement bars - D² / 533 Kg/ft. 
• Percentage of steel in Columns - 0.08% - 6% of gross area 
• Percentage of steel in Beams - 1% - 2% of gross area
• Percentage of steel in Slabs - 0.7% - 1% of gross area
• Main bars in the slabs shall not be less than 8mm (HYSD) bars or 10mm (Plain bars) and the distributors not less than 8mm and not more than 1/8 of slab thickness
• Minimum number of barsfor square column is 4nos. and 6 nos. for circular column
• Lapping is not allowed for the bars having diameters more than 36 mm (above that Couplers or welding only)
• Chairs minimum of 12 mm dia bars should be used
• Chairs spacing maximum 1 m or 1 no. per 1 Sqm
• For Dowels, minimum of 12 mm dia. rods should be used
• Binding wire required in reinforcements - 8 kg/MT
• "L" for Column main rods in footing - Min. 300 mm
• Hook for Stirrups - 9D for one side 

COVER TO MAIN REINFORCEMENT

• Column : 40 mm (D>12mm)
• Column : 25 mm (D= 12mm)
• Beam : 25 mm
• Slab : 15 mm (or) not less than dia of the bar.
• Footing : 50 mm
• Sunshade (Chajja) : 25 mm
• Retaining walls : 20 / 25 mm

CONCRETE

• Size of Concrete testing Cubes - 150 x 150 x 150 mm

• Weight of RCC - 2500 - 2700 Kg/ Cum
• Weight of PCC - 2400 Kg/ Cum

• Concrete cube is filled in - 3 Layers
• Slump Cone is filled in - 4 Layers 
• Thickness of Shear wall - Min. 150 mm , Max. 400 mm
• Slope of Staircase 25- 40 degree
• Minimum thickness of slab - 125mm
• Dimension Tolerance for Cubes - +/- 2 mm
• Free fall of Concrete allowed - Max. 1.50 m
• Water - Cement Ratio for different grades of Concrete shall not exceed 0.45 for M20 and above and 0.5 for M10 & M15
• Slump value required - For lightly Reinforced - 25- 75 mm and for heavily reinforced - 75 - 100 mm
• pH value of water should not be less than 6 for construction
• Cube Samples required - Upto 30 Cum - 3 nos., Upto 50 Cum - 4 nos., Above 50 Cum - 4+1 no. of additional sample for each 50 Cum 
• Compressive Strength required for Concrete: In 3 days - 45%, 7 days - 67 -70%, 14 days - 85%, 28 days - 100% +
• Clay and Silt content in Sand should not exceed 3% by weight or 8-10% by volume. For Crushed sand, Clay and silt content should not exceed 15% by weight
• Target strength of Concrete - 1.25 times design strength (Eg. For M40 - 1.25 x40)
• Cement Requirement  for M10 - 210 Kg, M20 - 320 Kg, M25 - 340 Kg, M30 - 380 Kg

• Water absorption of Bricks - 12% to 20% of of its self-weight when submerged in water for 24 hours
• Compressive strength of Bricks - 105 Kg/ Cm² or 10.5 N/mm² for I class bricks                                                                                  - 70 Kg/ Cm² or 7 N/mm² for II class bricks                                                                                        - 35 Kg/ Cm² or 3.5 N/mm²  minimum for  bricks
• Compressive strength of Fly ash Bricks -  90 to 100 Kg/ Cm² or  9 to 10 N/mm²

• In Soil filling, 3 samples should be taken in 100 Sqm for  testing dry density of soil by Core cutter test

DENSITY OF MATERIALS

• Weight of Cement                      - 1440 Kg /m³
• Weight of Steel                            - 7850 Kg/ m³
• Weight of Bricks                          - 1600 - 1920 Kg/ m³
• Weight of Block work                - 1920 Kg/ m³
• Weight of Coarse aggregates - 2600 - 2900 Kg/m³
• Weight of River sand or Fine aggregate - 1450 - 2100 Kg/m³
• Weight of RCC                              - 2310 - 2700 Kg/ m³

STRIPPING TIME ( De-Shuttering)

• For columns, walls, vertical form works : 16-24 hrs
• Soffit formwork to slabs                                : 3 days (props to be refixed after removal)
• Soffit to beams props                                     : 7 days (props to be refixed after removal)
• Spanning up to 4.50m                                    : 7 days
• Spanning over 4.50m                                     : 14 days
• Arches spanning up to 6m                           : 14 days
• Arches spanning over 6m                             : 21 days

CO-EFFICIENT FOR PAINTING

• Partly paneled and glazed doors : 0.80 times the door or window area.
• Collapsible gates                                : 1.50
• Corrugated sheet Steel doors       : 1.25
• Rolling shutters                                   : 1.10
• Flush doors                                           : 1.20
• Fully glazed doors                              : 0.80

GENERAL

• Electrical conduits shall not run in columns 
•  Earth work excavation for basement above 3 m Should be stepped form
•  Any Back filling shall be compacted 95% of dry density at the optimum moisture content and in layers not more than 200 mm for filling above structure and 300 mm for no structure
• Cement shall be stored in dry places on a raised platform about 200 mm above floor level and 300 mm away from walls. Bags to be stacked not more than 10 bags high in such a manner that it is adequately protected from moisture and contamination. 
• Initial setting time of Cement shall not be less than 30 minutes and Final setting time shall not be more than 10 Hours
• Groove cutting machine shall be used for chasing of walls for all electrical conduits
• 4" - 7" wide expanded metal mesh shall be fixed before plastering of all conduit chasing in walls
• For Column wall junctions & Beam wall junctions 4" wide expanded metal mesh shall be fixed before plastering
• Anti terminate treatment chemical Name is Chloropyrifos 20% . Diluting 5 Lit of Chemical with 95 Lit of water and usage is 7.5 Sqm Per litre {Diluted}. To Provide 1” Dia hole and Deep 1 Foot.
• One cement bag=1.25 Cft

Thumb rule requirement of standard materials in high raised building

• Steel =3 to 5 kg / sft
• Cement = 0.5bags/ sft
• RMC = 0.05 m³/sft
• Block =12.5 nos /sqm

Cement requirements in Plastering

• 200 mm in cm 1:6     -  0.124 Bags /sqm 
• 200 mm in cm 1:4     -  0.206 bags/sqm
• 150 mm in cm 1:6     -  0.093 bags/sqm
• 150mm in cm 1:4      -  0.144 bags/sqm
• 100 mm in cm 1:4     -  0.103 bags/sqm
• Ceiling plastering     -  0.11 bags/sqm
• Wall plastering          -  0.09 bags/sqm
• Rough plastering      -  0.09 bags/sqm
• Duct plastering          -  0.09 bags/sqm
• External plastering   -  0.175 bags/sqm

Cement requirements in PCC

• PCC 1: 4: 8      - 3.4 bags/cum
• PCC 1:5:10      - 2.52 bags/cum
• PCC 1:3:6        - 4.2 bags/cum
• PCC 1:2:4        - 6.02 bags/cum

Cement requirements in Brick work

• 230 mm brick work   - 0.876 bags/cum
• 115 mm brick work   - 0.218 bags/cum

Cement requirements in Flooring, Waterproofing

• VDF 100 mm thick  -  0.82 bags/sqm
• Granolithic flooring 40 mm  -  0.35 bags/sqm
• Granolithic flooring 20 mm  -  0.28 bags/sqm
• Anti-skid tiles laying -  0.28 bags/sqm
• Ceramic   tiles laying-  0.28 bags/sqm
• Vitrified tile flooring  -  0.28 bags/sqm
• Vitrified tile dado  -  0.27 bags/sqm
• Ceramic dado  -  0.27 bags/sqm
• Marble flooring  -  0.3 bags/sqm
• 100 mm heigh marble skirting  -  0.027 bags/rmt
• Marble cladding  -  0.27 bags/sqm
• Terracota tile flooring -  0.3 bags/sqm
• Mangalore tile  -  0.3 bags/sqm
• Door frame fixing  -  0.17 bags/sqm
• Water proofing for sunken slab  -  0.23 bags/sqm
• Water proofing for walls  -  0.23 bags/sqm
• Water proofing for balcony/toilets  -  0.65 bags/sqm

Conversion factors

• One Sqm            =  10.7639 Sft
• One Cum             =  35.314 Cft
• One Cubic metre = 1000 litre
• One Metre   =  3.280 Feet
• One Acres    = 4046.873 Sqm  =  43560.17 Sft  =  4840.019 Yards
• One Mile       =  1609.344 metre
• One Acre      = 100 cent
• One ground = 2400 Sft  =  5.51 cent
• One Mile     =  8 Furlong

• 
  

KNOW ABOUT RERA & TNRERA

KNOW ABOUT RERA

What is RERA?

The Real Estate Regulatory Authority (RERA) Act has been implemented to protect the interests of home buyers. As per RERA rules, real estate projects and developers or agents across the country have to register with RERA on the official RERA website for their state. In case of discrepancy in details, home buyers can reach out to RERA for dispute redressal and reimbursement.

Know about RERA Act in Tamil Nadu (TNRERA)

As per the RERA Act, each state of India must have its own Real Estate Regulatory Authority. The state RERA regulates the real estate sector within state limits. The Tamil Nadu RERA Act was passed in March 2016 as a part of this plan. TNRERA carries out all the activities specified under the parent act and regulates every segment of the real estate sector in Tamil Nadu.

Functions of TNRERA

In line with RERA's objectives, TNRERA performs the following functions.

• It promotes the rights of home buyers and developers
• It aims to create transparency in the state's real estate sector
• It has helped increase accountability in the sector and in real estate transactions
• It offers speedy redressal for disputes
• It aims to create a favourable environment for real estate investments.
• It encorages efficient and timely project execution
• It standardises the real estate development and construction Process

TNRERA Services 

The RERA Act Tamil Nadu offers a host of services to homebuyers, promoters and agents. 

Homebuyers can

• File an online complaint against developers, if they don't abide by the provisions of RERA Act Tamil Nadu.
• Access and details of all RERA registered real estate projects submitted by promotors or agents of the official Tamil Nadu RERA website.

Promoters Can

• File complaints online
• Register a real estate project under RERA Tamil Nadu
• File for the extension of the project
• Update details of a registered project on quarterly basis.

Real estate Agents can

• File complaints about builders online
• Renew their registartion ON the RERA Tamil Nadu website

TNRERA Fees and Charges

Developers and agents have to pay the following fees to register their property with TNRERA

For Registration of Real Estate Projects

• RS. 5 per sqm. of the plotted area for the layouts, sub-divisions and site approvals, excluding EWS plots

• For Residential buildings

1. Rs. 10 per Sqm. of FSI area, where the size of the  dwelling unit is  less than 60 Sqm
2.  RS. 20 per Sqm. of FSI area for other residential projects

•   Rs. 50 per Sqm. of FSI area for a commercial building
• Rs. 25 per Sqm, of FSI area for any other projects

Registration Fee for Real Estate Agents

• Rs. 25000 for an individual
• Rs. 50000 for anyone other than individual

RERA Forms for Buyers

• Appeal to Appellate Tribunal Form
• Complaint to authority Form - M
• Complaint to regulatory authority Form - N

RERA Forms for Developers

• Application for registration of project Form - A
• Declaration Form - B
• Registration certificate of project Form - C
• Intimation of rejection of application for registration of project or rejection of application for extension of registration of project or revocation of registration of project Form - D
• Application for extension of registration of project Form - E
• Certification for extension of registration of project Form - F
• Complaint to authority Form - M

RERA Forms for Agents

• Application for registration of real estate agent Form G
• Registration certificate of real estate agent Form - H
• Intimation of rejection of application for registration of real estate agent or rejection of application for extension of registration of real estate agent or revocation of registration of real estate agent Form - I
• Application for renewal of registration of real estate agent Form - J
• Renewal of registration of real estate agent Form - K
• Appeal to appellate tribunal Form - L
• Complaint to authority Form - M
• Complaint to regulatory authority Form - N

RERA Tamil Nadu Approved Projects List

To see the RERA registered properties in Tamil Nadu, visit official TNRERA website: 

https://www.rera.tn.gov.in/cms/reg_projects_tamilnadu.php

(Courtesy: Bajaj Finserve Website)

RERA Notifications 

Gazette-Notification-of-RERA-(26 March-2016) (Download)

TN Gazette Notification of TNRERA  (Download)

HOW TO CALCULATE MATERIALS REQUIRED

 CALCULATION OF MATERIALS

 FOR CONCRETE

For  Concrete Mix 1:2: 4 (M15) -1 Cum

Add 50% for Wet Concrete, ie., 1.5 Cum    (1.54 also can be taken)

Cement -1 part = 1.5/ (1+2+4)  = 0.214 Cum

                     1 Cum of Cement = 30 Bags of Cement  ( 1 Cum = 1440 Kg /50 = 30bags)

Cement required      = 0.214 x 30 = 6.42 bags

Sand required            = 0.214 x 2 = 0.428 Cum

Aggregate required = 0.214 x 4 = 0.856 Cum

FOR SOLID BLOCK MASONRY 8" tk. in CM 1:6 mix - 100 Sqm

Volume = 100 x 0.2 (Thickness of wall)   Block size - 0.4 x 0.2 x 0.2

                 =  20 Cum

Approx. no. of blocks required  = 20 / (0.4 x 0.2 x 0.2)

                                               = 1250 Nos.

Volume of Mortar          = 20-(0.39 x 0.19 x 0.19 x 1250)   (Deduct 10mm for mortar thickness)

                                              = 20 - 17.598

                                              = 2.40 Cum

Blocks                                 = 17.598 / (0.4 x 0.2 x 0.2)

                                               = 1100 Nos.

        Add 2% wastage     = 22

Total Blocks required   = 1122 Nos.

FOR WALL PLASTERING CM 1:4, 12 mm tk. - 100 Sqm

Volume              = 100 x (12/1000)          = 1.20 Cum

Add 30 - 35% as bulking of Sand        = 0.36 Cum

Add 20% wastage of Sand                     = 0.312 Cum

                                                  Total              = 1.872 Cum

 For 1: 4 mix, 1 part     = 1.872 / (1+4)  = 0.374 Cum

 Cement required        = 0.374 x 30       = 10.77 bags

Sand required               = 0.374 x 4         = 1.496 Cum

Mortar - increase 25% for dry mortar  = 2.4 + 0.6 = 3.0 Cum   (Upto 33% can be increased)

                                         For 1: 6 mix            = 3 / (1+6)

                                                                            = 0.429 Cum

               Cement Required   = 0.429 x 30 = 12.50 bags

                Sand                           = 0.429 x 6   = 2.57 Cum

FOR RED CLAY BRICK MASONRY 9" tk. in CM 1:6 mix - 100 Sqm

Size of Bricks (Traditional in India) - 225 x 112.5 x 75 incl. 10mm mortar joint.

Volume = 100 x 0.225 (Thickness of wall)   

                 =  22.5 Cum

Approx. no. of bricks required  = 22.5 / (0.225 x 0.1125 x 0.075)

                                               = 11852 Nos.

Volume of Mortar          = 22.5-(0.215 x 0.1025 x 0.065 x 11852)   (Deduct 10mm for mortar thickness)

                                              = 22.5 - 16.98

                                              = 5.52 Cum

Bricks                                 = 16.98 / (0.225 x 0.1125 x 0.075)

                                               = 8944 Nos.

        Add 2% wastage     = 179

Total Bricks required   = 9123 Nos. For 100 Sqm 9" tk. wall

CONVENTIONAL METHOD OF CALCULATION OF BRICKS

Size of Brick - 9" x 4.5" x 3" (0.75 x 0.375 x 0.25 ft)

Volume of Brick  = 0.75 x 0.375 x 0.25 = 0.07 Cft.

No. of Bricks in 1Cft. = 1 / 0.07 =14.285 Bricks

Quantity of Bricks without mortar = 14.285 - 1.4285  (Deduct 10% for mortar coverage)

                                                                       = 12.856 Bricks

Adding 5% wastage of Bricks            = 0.6428

                   Total no of bricks                 = 13.49 for 1 Cft of Brick work

                For 100 Cft Brick work           = 1349 Bricks

CALCULATION OF AGGREGATES

For 1:1.5:3 mix

Quantity of Aggregate  = Aggregate / (Cement+ Sand + Aggregate ) x 1.57

                                               = 3/ (1+1.5+3) x 1.57   = 0.85 Cum

! Cum of Aggregate        = 1500 to 1800 Kg 

  Let us assume 1650 Kg, Then 0.85 Cum Aggregate = 1650 x 0.85 = 1402.5 Kg.

A SIMPLE GUIDE TO ROAD WORKS

 ROAD WORKS - PROCEDURE, METHODOLOGY, TESTS & CHECKLISTS

Road works involve the process of strengthening the earth's surface suitably to enable easy movement of human and vehicular traffic over it.

IMPORTANT TERMINOLOGY

Road/ Pavement

It is a hard and even surface, for the smooth movement of vehicles, pedestrians, bicycles, etc.

Carriageway

The portion of the roadway that is designed and constructed to take vehicular traffic.

Shoulder or haunch or berm 

It is the portion of the road that is immediately beyond the edges of a carriageway which can be used by vehicles occasionally to pull over for short intervals or while crossing each other from opposite directions. 

Median 

The two carriageways of a road are separated by a strip of land along the road called as the median. The median can be used to fix streetlights, drains and also to create green areas. 

Kerb stones 

A hard stone, like granite, or pre-cast concrete member, of suitable dimensions, used to border a road, limiting the footway are called as kerb stone. 

Camber 

The slight convexity on the surface of a road is called camber. It is given to drain the water off the road during rains. A minimum camber of 2.5% is required for any road.

 

Sub grade

The under lying layer of the road, upon which the pavement structure is built is called as sub grade.

Wet Mix Macadam (WMM)

It is granular material for sub-base bound by water. It is essentially an

aggregate material of specific grading.

Water Bound Macadam (WBM)

It is a tightly bound, strong and semi-pervious surface. Water bound macadam (WBM) comprises two components, a layer of coarse stone (37.5mm to 75mm size) into which graded fine aggregate (5mm size) is slurried or washed. It can be used as an unpaved surface or as a base material on roads with bituminous seals.

Bituminous Macadam (BM)

One or more layers of well graded aggregates, sized between 0mm to 40mm, each layer bound by bitumen is called as bituminous macadam.

Granular Sub Base (GSB)

It is a layer of selected material such as moorum, gravel, laterite, etc, over the prepared sub grade in layers of designed thickness.

DBM

Dense Bituminous Macadam.

Asphalt concrete

It is a premix of bitumen, sand and mineral aggregate (larger than sand size), with or without a filler material in prescribed proportion.

Asphalt concrete base course (tack coat)

One or more layers of asphaltic concrete of specific design given on top of the Dense Bituminous Macadam (DBM).

Cut and fill

It is the process of excavation (cut) or raising the natural ground level (fill) by depositing suitable material in a prescribed way, to achieve a desired formation level is called as cut and fill.

Culvert

A sewer or drain crossing under a road or embankment.

CBR

California Bearing Ratio.

ROW

Right Of Way. It is a path or strip of land over which someone has the legal right to pass.

PROCEDURE

Before construction:

• All the necessary latest GFC drawings and complete specification details like alignment of the road, width of carriageway, kerbs, drains, shoulders, camber etc. should be available.

• Proper inspections chambers should be planned and provided for the sewage lines at         suitable locations.

• Any necessary cutting with respect to the level of the roads should be done.

• All unsuitable excavated material (especially black cotton soil) has to be disposed away at a suitably approved dumping site. However, fertile soil can be stocked suitably and can be used for landscaping along the sides or on the median of the roads.

• The entire area along which the road shall be aligned should be cleaned of any debris, rocks and vegetation.

• Trees shall be transplanted and loss of vegetation should be minimized.

• The soil test reports should be available at site.

• Before proceeding with the construction of the road section, the underlying sub grade has to be compacted and tested to ensure the strength as per specifications given by the consultant.

During construction:

• The proposed road areas have to be surveyed to establish the of the road 

sections according to the GFC drawings.

• As per drawing, establish bench mark pillars along the length of the road on either sides at intervals of 5 to 10m.

• The sub-grade is prepared by cutting/ filling (embankment) to the required level.

• The underlying cut areas have to be scarified and then given the rough profile of the road during the compaction process using a single drum roller. 98% of the maximum dry density of the soil should be the achieved compaction and a minimum of 8% CBR.

• The density of the compacted soil has to be checked by using sand replacement method or by using a nuclear gauge. This compacted soil should be able to take up the loads as per design.

• Usually, after the sub grade work is finished, all the underground utilities, ducts, culverts, etc shall be installed.

• Electrical, sewage/ water line, which cross the alignment of the road, should be completed as per requirement. The water lines should be above the sewage lines.

• Sub grade material shall be placed where ever required and compacted in layers not exceeding 150mm (after compaction), to the desired level, to achieve the required compaction.

• A layer of Granular Sub Base (GSB) shall be laid in a maximum thickness of 150mm (after compaction) per layer and compacted to the required level.

• After spreading the granular sub base, it shall be watered and rolled to achieve the desired compaction using a single drum vibratory roller.

• The aggregates shall be slightly wet during this process — say 5% to 7% moisture content.

• While laying the granular sub-base, the camber and profile of the road has to be maintained as per the GFC drawings.

• Upon the completion of the GSB layer, gutters shall be installed to line and level as per the GFC drawings, before laying the wet mix macadam.

Wet Mix Macadam (WMM) consisting of graded and granular material which is premixed with water, is laid in one or more layers not exceeding 150mm each (after compaction), leveled with a grader 0 and then compacted with a vibrating soil compactor.

• The top of this layer should have the profile and slope as per GFC drawings.

• On the complete layer of wet mix macadam, prime coat shall be applied using a bitumen sprayer at the rate of 0.8 — 1.2 liter/ m2  .

• If cut back bitumen is being used to prepare the primer, then a curing period of 24 hours is mandatory before laying the DBM.

• If a bituminous emulsion is being used as a primer, then DBM works can successively continue.

• Then bitumen is heated to 180°C and mixed with well-graded aggregates of size 20mm in a bituminous concrete batching plant to get DBM. The mix should be as per design from the structural consultant.

• DBM is transported in dumpers and fed into the paver machine.

• The paver machine will lay the DBM to the required thickness, level, alignment and width as per the GFC drawings.

• The temperature of the asphalt base course at the time of laying and rolling by the paver machine should not be less than 120°C. 

• Double drum vibratory rollers are then used to further compact and is finished using a pneumatic roller.

• Above this asphalt base course, a layer of tack coat (at the rate of 0.4 — 0.6 liter/ m2) is sprayed with a bitumen sprayer.

• The asphaltic concrete wearing course is then laid using a paver machine and rolled with double drum vibratory rollers. This is also called as the seal coat. The design mix of the wearing course shall be as per approved specifications.

• A pneumatic roller is used for the compaction of this layer.

• No vehicular traffic should be allowed on the freshly laid road for a minimum of 12 hours.

After construction

• Upon completion of the road construction, the pavement marking, fixing of road signs, markers, reflectors, convex mirrors, painting of kerb stones, etc should be completed.

• The walking area next to the road has to be built as per design.

• Poles for street lights, signals and other signages should be installed and all electrical works should be completed.

       All the storm water lines, sewer lines and other utilities shall be tied to their corresponding main lines at suitable locations as given in the drawings.

Installation of kerb/ gutters

• Prior to the start of the kerb/ gutter installation, all underground utility crossings, drains and ducts should be completed.

• The granular sub-base layer should be completed.

• The top of the kerb stone should be at a height of 150mm above the top of the finished road

level.

• PCC base shall be cast in place along the line of the kerb to the required width.

• The kerb stones are fixed on this PCC layer, using cement mortar 1:5.

• String line should be used to ensure exact alignment of the kerbstones along the length of the road.

• A gap of 3 to 5mm should be maintained between any two consecutive kerbstones.

• A minimum of 7 days curing should be done.

Interlocking paver fixing

Interlocking pavers are pre-cast concrete elements that can be used for both walk ways and for vehicular traffic.

After fixing, each paver becomes integrated to form the pavement because of the interlocking

system and hence have high load carrying capacity. The finished surface provides good grip for vehicles. The interlocking pavers can be of different colours and shapes.

• The area where the interlocking pavers have to be installed shall be well compacted using vibratory rollers or earth rammers to achieve desired compaction.

• A layer of sand/ crushed sand shall be laid and compacted to a thickness of 40 to 50mm.

• The interlocking pavers are then laid in a pattern as per design.

• The interlocking pavers shall be fitted and secured in place using a rubber hammer to the required level.

• All the closure gaps at the edges and corners shall be fitted with cut pieces of right sizes.

• All the joints between the pavers shall be packed with sand to fill all gaps.

• The top of the interlocking pavers shall be flooded with water to ensure proper packing.

QUALITY INSPECTION METHODOLOGY

• The top level of different layers has to be checked and should be as per design.

• Check the camber given to the road and the slope of the banking given at curves.

• The aggregates used shall be well graded and should fall within the

prescribed size.

• The temperature of the asphalt base course during laying should not fall below 120°C

• Check the thickness of the different sections of the road with respect to the GFC drawings.

• The bitumen prime coat and tack coat application should not exceed the prescribed limits.

 This is because, when the road gets heated up under the sun, the excess primer tends to melt and ooze out of the top of the road. This phenomenon is called as bleeding.

• Check if proper slope has been given for the drains so that water does not stagnate. 

• Check the functioning of all electrical  and communication services provided along the road and the location of the signboards and reflectors.

TOOLS AND EQUIPMENTS

NAME	USE
Soil compactor	Compaction of the existing soil
Pad foot attachment	Accessories to Soil Compactor
Bull dozer	Leveling soil and aggregates
Excavator	Excavating of soil and aggregates
Wheel-loader	Moving all types of construction materials
Backhoe-loader	Excavating of soil and moving aggregates
Motor grader	For planing aggregates
Tandem roller	Compaction of aggregates and bituminous layers
Pneumatic roller	Compaction of bituminous Top layer
Hand held roller	Compaction of soil, aggregates and bituminous layers
Plate vibrator, large	Compaction of soil and aggregates
Plate vibrator, small	To compact pavement
Stone saw	Cutting all types of stone materials
Asphalt paver	Lay bituminous macadam
Asphalt plant	Mixing all types of bituminous materials
Bitumen storage tank	Bearing bituminous primer
Liquid-bitumen sprayer	Application of bituminous primers
Bitumen tanker	Conveying bituminous primers on site
Water tank	To store the water used for different activities
Asphalt cutter	To attain a straight top layer
Paver	To lay the different layers of bituminous macadam

LABORATORY TESTS

  

S. no	Name of the Lab test		Reader	Frequency	Acceptability Criteria
1.	Binder temperature			At regular close intervals
2.	Rate of spread of aggregates in surface dressing			One test per 500sqm of work, and not less than two tests per day	Mean value of aggregate quantity to be not less than the specified value +/- 1.65
					(No of samples)" time standards deviation.
4.	Water sensitvity		AASHTO-T- 283-89	One test of 3 specimens for each source of supply	Accept if the minimum retained strength is above the specified value.
5.	Binder content of mix and aggregate grading for  ituminous Macadam		Aaphalt Institute Manual MS-2	Periodic, subject to minimum of two tests per day per plant	Accept if the binder content is not less than the specified value +/-1.65
					(No of samples)" times standards deviation. Accept grading if within specified limits.
6.	Binder content of mix and aggregate grading  for Dense Bituminous Macadam/ Semi- dense Bituminous concrete		Aaphalt Institute Manual MS-2	One test per 400 tonnes of mix, subject to a minimum of two tests per plant per day	Accept if the binder content is not less than the specified value +/-1.65
					(No of samples)" times standards deviation.  Accept grading if within specified limits.
7.	Aggregates grading for Bituminous Macadam		IS:2386- Part 1	Two tests per plant per day both on the individual constituent and mixed aggregates from the dryer	Accept if the grading is within specified limits
8.	Aggregate grading for Dense Bituminous Macadam/ Semi-dense Bituminous Concrete and bituminous Concrete		IS: 2386- Part 1	One set of test on individual constituents and mixed aggregate from the dryer for each 400 tones of mix subject to a minimum of two tests per plant per day	Accept if the grading is within specified limits
9.	Stability of Mix		Asphalt Institute Manual MS-2	For each 400 tonnes of mix produces, a set 3 Marshal specimens, subject to a minimum of two sets per plan per day	Accept if the mean stability is not less than the specified value plus 1.65
					1'65 (No of samples)05 times standards deviation.
10.	Temperature of bitumen in boiler and aggregate in dryer			At regular close intervals
11.	Density of compacted mix			One test per 250sqm of area	Accept if the mean density is not less than the specified value plus 1.65
					1.65- of samplesr times standards deviation.
12.	Rate of spread of mixed material			At regular intervals through checks over layer thickness
13.	Softening point of modified binder		IS: 1205	Initially on submission, and thereafter daily if site blended and weekly if pre-blended	Accept if variation from recommended value is not more than 1.65 times the standard deviation
14.	Penetration at 25°C and 4°C of modified binder		IS:1203 and IS:1205	Initially on submission, and thereafter daily if site blended and weekly if pre-blended	Accept if variation from recommended value is not more than 1.65 times the standard deviation
15.	Elastic recovery of modified binder		ASTM D 5976- 1996 appendix II	Initially on submission, and thereafter daily if site blended and weekly if pre-blended	Accept if variation from recommended value is not more than 1.65 times the standard deviation
16.	Ductility of modified binder		IS: 1208	Initially on submission, and thereafter daily if site blended and weekly if pre-blended	Accept if variation from recommended value is not more than 1.65 times the standard deviation
17.	Flash point of modified binder		IS: 1209	Initially on submission, and thereafter daily if site blended and weekly if pre-blended	Accept if variation from recommended value is not more than 1.65 times the standard deviation
18.	Fraass breaking of modified binder		IS: 9381	Initially on submission	Accept if variation from recommended value is not more than 1.65 times the standard deviation
19.	Viscosity at 150°C of modified binder		IS: 1206	Initially on submission	Accept if variation from recommended value is not more than 1.65 times the standard deviation
20.	Thin film oven test, penetration, softening point, elastic recovery of residue and loss on heating of modified binder		IS: 9382	Initially on submission	Accept if variation from recommended value is not more than 1.65 times the standard deviation
CONCRETE PAVEMENT
S. no	Name of the Lab test		Reader	Frequency	Acceptability Criteria
1.		Cement	IS: 269 IS: 455 IS: 1489 IS: 8112 IS: 12269	Once for each source of supply and occasionally when called for in case of long/ improper storage	Accept if the test results are within prescribed limits
2.		Gradation of Aggregates	IS: 2386 -  Part 1	One test for each day's work; periodicity may be relaxed later at the discretion of the engineer	Accept if the gradation falls within the prescribed limits
4.		Deleterious constituents of aggregates	IS: 2386- part 2	One test for every day's work initially may be relaxed later at the discretion of the engineer	Accept if the deleterious contents are less than the limits prescribed
5.		Water absorption of aggregates	IS: 2386- Part 3	Regularly as required, subject to a minimum of one test a day for coarse aggregates and two tests a day for fine aggregates,	The water absorption data shall be used for correcting the water demands of the mix on a daily basis.
6.		Los Angeles abrasion of aggregate impact value	IS: 2386- Part 4	One for each source of supply and subsequently on a monthly basis	Accept if the result is not more than the specified value by 1.65 times the standard deviation.
7.		Soundness	IS: 2386- Part 5	Before approving the aggregate and every month subsequently	Accept if the test value is below the specified value.
8.		Alkali-Aggregate reactivity	IS: 2386- Part 7	Before approving the aggregate and every month subsequently	Accept if the test result conforms to the value specified
9.		Water	IS: 456	Once for approval of source of supply, and subsequently only in case of doubt	Accept if the test result conforms to the value specified
10.		Concrete strength	IS: 516	2 cubes and 2 beams per 150 cum (one for 7 days and one for 28 days), or a minimum of 6 cubes and 6 beams per day's work, which ever is more	Accept if the mean value is not less than the specified value plus 2.33 times the standard deviation and value as strength less than the specified value.
11.		Core strength of hardened concrete	IS: 516	As per the requirements of the engineer, only in case of doubt	Accept if the individual test result is more than the specified value
12.		Workability of fresh concrete (Slump test)	IS: 1199	One test for each dumper load at both batching plant site and paving site, initially when work starts. Subsequently, sampling may be done for alternate dumper
12.		Thickness		From the level data of pavement and sub- base at grid points of 5/ 6.25m x 3.5m	Accept if the tolerance is -5mm to +25mm of specified thickness
Control of alignment level and surface regularity
S. no	Name of the Lab test		Reader	Frequency	Acceptability Criteria
1.		Horizontal alignment			The edges of the carriageway shall be correct within a tolerence of ± 10mm from the designed aligment. For lower layers of the pavement, the tolerance is ± 25mm
2.		Surface levels a)          Sub-grade b)          Sub-base (i)     Flexible pavement (ii)    Concrete pavement			Tolerance allowed + 20mm — 25mm + 10mm — 20mm + 6mm —10mm
3.		(c) Base course or flexible pavement (i) Bituminous (ii)    Other than bituminous (machine laid) (iii)   Other than bituminous (manually laid)		+ 10mm — 10mm + 15mm — 15mm	+ 6mm — 6mm
4.		(d) Wearing course for flexible pavement (i) Machine laid (ii)        Manually laid   (iiI) Cement concrete pavement			+ 6mm + 6mm   + 10mm —10mm   + 5mm — 5mm
5.		Surface regulatory measured by 3m straight edge (a) Bituminous surface course (b)Bituminous base course (c) Granular sub-base/ baserse (d)Sub-base concrete pavement (e) Concrete pavement surface			3mm   6mm   8mm   1Omm     3mm

 

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