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Showing posts with label Reinforcing steel. Show all posts
Showing posts with label Reinforcing steel. Show all posts

Friday, April 19, 2019

Detail quality control methods in construction works

This civil engineering article sheds light on the inspection method of various civil works as well as necessary documents to carry out an inspection at construction project.

Civil Inspection: Purpose - It is conducted to verify that the civil construction activities accomplished on the construction projects adhere to relevant codes, standards, specifications and drawings.

Scope: The method will involve general inspection standards in relation to safety, survey control, soils inspection, reinforcing steel inspection, concrete inspection, grouting inspection, structural steel inspection.

Construction activities and consequent inspection standard should be based on job site specifications, methods and drawings. As a replacement for jobsite specifications or where referenced with jobsite specifications, national codes and standards should be employed.

Responsibility: Normally, the Main contractor and subcontractors should take the liability to make sure that construction activities are executed compliant with suitable specifications, procedures, drawings, codes and standards.

The contractor is empowered to execute whatever inspections and tests are assumed necessary to make sure that construction activities are accomplished as per job requirements and/or to involve sub-contractors and/or testing agency personnel to conduct these inspections and tests. Contractor is also empowered to evaluate the qualifications of all subcontractor and/or testing agency personnel doing inspections and/or tests, and substitute that personnel if their qualifications do not deem fit for the inspections and tests being executable.

Reference Documents: Given below, a incomplete list of reference documents which are suitable in applying this procedure.

• International standards
• Local Authority codes & specifications.
• Specifications of the project


Safety: Every employee should take the liability for his or her personal safety as well as for others. Each employee should be well versed with the perfect for his or her work. Employees must abide by the personal responsibility for cooperating and conforming to all HSE policies and methods. Before starting the work, all employees must evaluate and gather knowledge on of all relevant safety methods provided in the Construction HSE Policies and Procedures Manual.

Survey Control: Normally, it should be the liability of the main contractor’s/ subcontractors to provide his own survey crew as well as set up survey control for the persistent construction depending on the previously settled control monuments. The contractor should set up and sustain survey control to the precision necessary to satisfy the industry and job site standards and requirements. The contractor may hire a separate survey company instead of employing in house personnel, but may not employ the same survey crew and/or company presently appointed by others in similar project.

Soils Inspection: Earthwork construction works should done as per job site specifications, methods and drawings. Soils inspection should be done by qualified personnel who will ensure that requirements of the specifications, procedures and drawings are fulfilled.

Reinforcing Steel Inspection: Reinforcing steel should be acquired, preserved and managed compliant with procedures of Receipt, Storage and Handling of Products. As part of the receipt inspection, mill test reports should be examined against the exact ASTM standards and fabricated bars should be arbitrarily verified against the bar lists for compliance. Any nonconforming items shall be treated according to procedures.

To get more details, click here (theconstructionpoint.com)

Detail quality control methods in construction works

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Published By
Rajib Dey
www.constructioncost.co
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Friday, August 31, 2018

Definition and categorisation of Pre-Stressed Concrete

Normal concrete structure contains greater compressive strength and very weak tension strength. For the purpose of removing the weakness of concrete in tension, pre-tensioning method is applied. Pre-stressed concrete belongs to the autonomous formation of permanent compressive stresses in a structure to enhance its behavior and strength toward different service situations.

Categorization of Pre-stressed concrete

Pre stressed concrete structure is categorized on the basis of their features of design and construction. The are categorized into the following three groups.

1. Location of construction
2. Level of construction
3. Method of pre-stressing


LOCATION OF CONSTRUCTION
Here, the pre-stressed structure may come as precast cast, cast in situ, composite constrictions.


PRE CAST
Precast pre-stressed components are fabricated in a plant or adjacent to the working site. Then they are conveyed to construction site and then they are constructed and set to its position.


CAST IN SITU
The cast-in-situ concrete is standard concrete that is poured into the exact formwork on the site and cured to attain the strength of RCC elements. So, the transportation and erection process are not necessary in this method.


COMPOSITE CONSTRUCTION
Composite construction is done by integrating both prestressed and cast in situ methods. As for instance, in a beam in a building structure is built up by pre-stressed concrete and the top roof slab is built up by the cast in situ method.


LEVEL OF PRE-STRESSING
Level of pre-stressing is categorized as completely pre-stressed, limited pre-stressed, partially pre-stressed.


FULLY PRE-STRESSED
In fully pre-stressed concrete members, there is not any tensile stress under the operation of working or service loads.


LIMITED PRE-STRESS
Members are pre-stressed to a limited extent in order that members may create some tensile stress under working loads but the magnitude is below the tensile strength of concrete. These members function as a completely pre-stressed member and remain uncracked under working loads.


PARTIALLY PRE-STRESSED
Partially pre-stressed structure contains both pre-stressing steel and reinforcing steel to withstand working load.


Partial pre-stressing is useful for both pre-stressed concrete and reinforced concrete. The tensile stress remains within the limit.

To get more detail, go through the following link learntocivilfield.com

Definition and categorisation of Pre-Stressed Concrete

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Published By
Rajib Dey
www.constructioncost.co
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