How can prevent corrosion in steel.

How can prevent corrosion?

A report published in The Times of India (in 2012) mentions that due to the steel war, India loses more than two lakh crores every year. Across the world, the corrosion described in the same report results in loss of steel of 25,000 tonnes per minute. This is the reason why it is important to apply corrosion control measures to improve the efficiency and longevity of properties, and reduce the loss.

Before looking ahead in the process of prevention of corrosion, let's find out what the corrosion is?

What is corrosion?
Corrosion is the process where a material worsens as a result of interaction with its environment. Corrosion is the main reason for the decline of metal. Corrosion metals are corrosion because they want to return to their stable form. Many metals or alloys have to undergo exposure to water or air. However, this process can be facilitated in the exposure of other substances.

How to prevent war?

There are several ways to prevent corrosion. These are:

1. Avoid contact with corrosive agents:
Withholding corrosive agents with your contact and preventing degradation of metals. For example, protect the metal content with rain water or protect excessive moisture by arranging it inside the house. In addition, should be limited in contact with high chloride-rich substances (like salt water). For example, to prevent corrosion, treat the water under the water boiler with the Softener.

2. Proper monitoring of metal surface:
Carefully monitor the metal surface. Look for cracks and crevices. These manufacturing errors can also be corrosion. In addition, use corrosion-resistant products. For example, if you are buying TMT times for construction, then select corrosion resistant bars (like SRMB TMT bars). Corrosion-resistant TMT bar ensures the longevity of the structure.

3. Prevent Galvanic Corrosion:
When two different metals are exposed to each other in the electrolyte, then acts as a metal anode and acts as the second cathode. The presence of electrolyte acts as a vascular for the ion migration to carry metal ions from anode to the cathode. When the cathode is gradually spoiled, this anode destroys metal more quickly. The result is in the galvanic jungle. This type of corrosion is common in gas or oil pipelines, huts of vessels and boats etc. To prevent galvanic war, apply a protective coating on the surface of the metal. It provides electrolytes with ion flow between metals. Providing Cathode protection by using a metal metal anode in the electrolytic environment also protects metals.

4. Protect Metal Surface:
Paints can be used to protect the metal surface from corrosion. Paint creates a protective barrier between metal surface and corrosive agent. For example, coating the outdoor metal units with coats of paint is saved in contact with rain water or snowfall etc. Many solutions, such as galvanized zinc coating, paint or oil sealant, can be used to prevent forests.

5. Metal plating:
Metal plating can be applied to prevent corrosion. General electrolysis of metal plating (covering surface with layer of tin or nickel), mechanical plating (applying zinc or cadmium on metal surface), electrolysis (coating with cobalt or nickel), or hot dip (melted) Zinc is included in the finished metal)
Hopefully, these points will give you an idea about ways to stop the war.

Top 5 REASONS FOR BUILDING CRACKS

There are many causes of cracks, anything, from natural causes like the recent tremors to using wrong or inadequate building materials.

Cracks may appear in the walls bricks/block mortar plaster, beam-wall joints, columns –wall joints, slabs, beams, columns, foundations and in many other places.

Much as it’s not a simple task, it’s essential you take any cracks seriously and get assessment done in order to specify their significance.
Most buildings will develop cracks at some point in time during their service life due to the following causes.

1.Poor workmanship

Poor mixing of building materials, like cement sand and aggregate will cause cracks in the walls, beams, slabs etc. Normally poor workmanship is as a result of ignorance, carelessness, negligence, lack of proper supervision and many others or worth still a combination of all these.

2.Temperature variations 

It’s important to know that most materials tend to expand when subjected to direct sunlight and contract in cooler temperatures this process, and therefore end up causing cracks. The cracks will be severe, especially in thin walls that are exposed to direct sunlight.

3.Structural design

Poor structural design and specifications are another cause of the cracks in concrete works. It’s important that the designer considers all the environmental aspects that include soil (Geotechnical) investigations that will enable the designer to come up with a proper design of the foundation.
Normally, buildings are designed for particular uses, and also to withstand a given measure of weight (loading) for example a building designed as residence will have different structural specifications from the one designed to operate machinery.

4.Lack of (or) poor maintenance

It’s always important to take good care of your house, by doing maintenance works after a lapse of certain periods. This will keep the building intact and also extend their life span.

5.Natural forces

Earthquakes, tremors like the ones that were experienced in Kampala recently, winds, rains, flooding and many others may cause cracking in the buildings.
There are many other causes and types of cracks in buildings therefore always look out for them and take the necessary actions.

Please note that, the remedies or solutions are not discussed because, of the various technical reasons, and therefore the solutions can be provided by technical people, However knowing the causes will help you to ask some crucial questions, and also have helpful awareness before, during and after the construction of your house.

Building foundation

Foundations

Foundation is the basic and the lowermost part of a structure. It provides an uniform base for the super structure and transfers the load of the same down to the soil.

Purpose of foundation

it should not be misunderstood that foundation is provided to support the super structure but should be noted that it is an element which just transfers the load of structure on to the hard bed upon which it lies. foundation is provided for the following main purpose:

1. To provide a level and uniform base to the super-structure.
2. To distribute the load of the structure on a large area of hard pan and also top ensure uniform distribution of load over the soil beneath
3. To provide good anchorage imparting stability to the super-structure  to prevent overturning

Site Investigation

1. To determine the safe bearing capacity of the soil
2. To determine the depth of hard bed upto which the foundation are to be taken to
3. To decide the design suitable, safe and economical foundations.
4. To determine the level of ground water table.
5. To predict the likely settlement of sub soil under loads and to make suitable allowance for the same in the foundationdesign

This can be detremined by simply digging a trial pit of suitable size and depth upto hard bed.

Types of foundations:

Foundations can be classified as 

Shallow Foundations: - Ordinary type buildings

Deep Foundations:- Heavy Loaded foundations

Spread footing foundation

As the name implies the spread footing foundation consists of widened fottings at base of the foundation to transmit the load of the structure uniformly on a greater area. In general all type of foundation have spread footings in one form or other . However from point of view of the material used in the construction its design and the construction technique they are further divided into following categories.

1. Spread footing for walls.
2. Reinforced concrete fottings. 
3. Footings for columns.
4. Grillage foundation.
5. Raft foundation.  

Spread footing for walls

In this type of foundation the base of the wall is widened by means of suitable offsets at foundation level. These may be brick or stone masonry usually a bed of lean concrete is provided below the course of brick or stone masonry footings to a afford a level and strong base. This course of concrete rectifies the inequalities of excavation and also bridges over soft patches in the soil below it. The grade of concrete used for such footings is usually 1:3:6 or 1:4:8 (cement:sand:aggregate) or lime concrete comprising 40mm size stone or over burnt brick aggregates with 40% mortar of 1:2 (lime:sand) or 1:1:1(lime:surkhi:sand)

The principle adopted for footings are:

1. The thickness of the concrete bed should not be more than 15 cm. It generally varies from 20 to 30 cm. But it should not be more than the thickness.
2.  The course of footings are generally 10 to 30 cm in depth the offsets provided are usually 5 cm for brick masonry and 8 cm for stone masonry
3.   general thumb rule followed are

• ·         Width of super-structure wall                           : T 
• ·         Width of foundation concrete                           : 2T+30CM
• ·         Width of bottom most course of footings       : 2T
• ·         Depth of concrete block                                      : (2/3) T

These type of footings are most commonly used ones and are economical as compared to other types of foundations for ordinary types of buildings. Structures in soils with moderate bearing capacity can be safely constructed with this type of foundations.

Reinforced concrete footings

These types of foundations are used in case of soil with low bearing capacity. In these type of foundations, reinforced concrete bed will be provided in place of a lean concrete bed. As per rules the base of the foundation are to be made wide enough to load the soil within its bearing capacity. Lean concrete bed is to be made much deeper to obtain the required width and this is totally uneconomical. Reinforced cement concrete can be provided in such cases since they are thin and economical as compared to lean concrete beds. A 7 to 8 cm thick lean concrete bed is usually provided below RCC bed to give a level surface .

Footings for columns

This is an independent footing and is provided under a column for distributing the concentrated load of the column over a large area uniformly. The shape of the footing may be either square, rectangular or circular in plan. The base area of the footing is obtained by dividing teh load of the column and its self weight with the safe bearing capacity of the soil . The requried base area is obtained by means of sitable offsets symmertical around the column.

LAP LENGTH FOR COLUMN BEAMS AND SLAB

LAP LENGTH FOR
COLUMN = 50 D
BEAM = 60 D
SLAB = 60 D

D=DIAMETER OF THE BAR.

IF DIAMETER IS 16MM

COLUMN = 50*16= 900MM
BEAM = 60*16 = 960MM
SLAB = 60*16 = 960MM

HOW TO CALCULATE DEAD WEIGTH OF CONCRETE SLAB

THE UNIT WEIGHT OF RCC SLAB IS 2500KG/SQM

JUST MULTIPLY THE SLAB THICKNESS AND AND YOU HAVE THE DEAD LOAD OF THE SLAB THICKNESS

EXAMPLE

DEAD LOAD OF THE SLAB 150MM (0.15M) SHALL BE:

2500*0.15=375KG/M

TOTAL DEAD LOAD ON SLAB

EXAMPLE 

LENGTH:-8M

WIDTH:-6M

AREA = 8M*6M=48SQM

DEAD LOAD

2500*0.15*6*8=18000KG

=18 TONNES

DEAD LOAD IN THE FORM OF UDL

ASSUME EFFECTIVE SPAN = 6M

SO, UDL =18000/6= 3000KG/M.

STAIRCASE DESIGN

STAIRCASE DESIGN

HOW TO DESIGN A STAIRCASE

CONSIDER YOU HAVE STAIRCASE ROOM  OF 4.5M X 2.0M AND HEIGHT OF THE ROOM IS 3.0M

SIZE OF THE ROOM = 4.5M X 2.0 M
HEIGHT = 3.0 M
ASSUMING WIDTH OF THE STAIRCASE AS 1.0M

PROVIDE TWO FLIGHT WITH MID LANDING HEIGHT OF EACH FLIGHT
                      = 3.0 / 2 = 1.5 M

ASSUME 15 CM RISERS

NO OF RISERS REQURIED IS = 150 / 15 = 10 NOS

ASSUMING 25 CM TREAD

LENGTH OF THE FLIGHT = (10-1) 25 = 225 CM

WIDTH OF LANDING  = 1.0M

SPACE LEFT FOR PASSAGE  = (4.5-1-2.25) = 1.25 M

SO PROVIDE

25CM TREAD AND 15CM RISERS WITH 1.0M WIDE MID LANDING.

REAL ESTATE REGULARATY & DEVELOPMENT ACT (RERA)

REAL ESTATE REGULARATY & DEVELOPMENT ACT (RERA)

Real Estate Act

Improve the perception of the sector among various stakeholders

Uniform regulatory environment

COMMERCIAL and  RESIDENTIAL projects including  PLOTTED DEVELOPMENT

RESIDENTIAL projects including  PLOTTED DEVELOPMENT

Land under development MORE THAN 500 SQ MTS / NO. of UNITS exceeds  8

Projects which do not have COMPLITION CERTIFICATE before  commencement of ACT

RENOVATION or REPAIR or REDEVELOPMENT projects not involving Marketing, Advertising, Selling & New Allotment NEED NOT BE REGISTERERD

Financial Maters

70% of the funds collected from allottees  needs to be parked in the project account

Withdrawals to cover construction and  land cost

In proportion to the % completion method

Withdrawals to be certified by Engineer, Artichect , and CA

Provision for RERA  to freeze project bank account upon noncompliance

Projects Account  to be Audited / FY . Copy to be submitted  to RERA

Provision for stronger  financial penalties  for RERA  noncompliance

Interest  on delay will be  same for  customer and promoter

Promoter to compensate  buyer for incorrect  statement  with  full rerun of  property cost  with interest

Transparency Details

Number, type & carpet area of apartments

Consent from affected allottees for any major addition or alteration

Consent of 2/3rd allottees for any other addition or alteration

No false statements or commitments in advertisement

Quarterly updating RERA website with details such as unsold inventory & pending approvals

No arbitrary cancellation of units by promoter

Project complition time frame

Informing allottees for any minor addition or alteration

No Launch or advertisement before registration with RERA

Consent of 2/3rd allottees for transferring majority rights to 3rd party

Accountability

Quarterly update of  project progress along with  pending approvals  on RERA website

Every office of the company , who as in charge or responsible  will be liable for the conduct of the company and deemed guilty

Offence by an officer committed with the consent or connivance of any director , manager , secretary or other officer of the company  , will also  be guilty

Authenticated copy of all approvals, commencement certificate, sanctioned plan, layout plan of development work, proposed facilities, proforma allotment letter, agreement for sale & conveyance deed to be given when applying for project registration with RERA

Registrations of brokers/agents with RERA

Timely updating of RERA website

Maximum 1 year extension in case of delay due to no fault of developer

Annual audit of projects account by a CA

Dispute resolution within 6 months at RERA and FERA (Foreign Exchange Regulation Act) appellate rebalance

Developers to share details of projects launched in last 5 years with status and reason for delay with RERA

Conveyance deed for common area in favor of RWA

Mandatory registration of new and existing  projects with RERA  before launch

Separate registration of different phases of a single projects

Construction and land title insurance

Project completion time period