13-02-2013, 09:24 AM
REINFORCING DETAILING OF R.C.C MEMBERS
[attachment=50612]
WHO IS AN ENGINEER?
According to USA President Herbert Hoover, who was an engineer before he became a politician, said:
The great liability of the engineer …compared to men of other professions……is that his works are out in the open where all can see them.
His acts …..step by step …are in hard substances.
He cannot bury his mistakes in the grave like the DOCTORS.
He cannot argue them into thin air…..or blame the judge…..like the LAWYERS.
He cannot, like the ARCHITECT, cover his figures with trees and vines.
He cannot, like the politicians, screen his shortcomings by blaming his opponents….and hope the people will forget. The ENGINEER simply cannot deny he did it.
If his works do not work……he is damned.
A design engineer’s responsibility should include assuring the structural safety of the design, details, checking shop drawing.
Detailing is as important as design since proper detailing of engineering designs is an essential link in the planning and engineering process as some of the most devasting collapses in history have been caused by defective connections or DETAILING. There are many examples explained in the book" DESIGN AND CONSTRUCTION FAILURES by Dov Kaminetzky.
Detailing is very important not only for the proper execution of the structures but for the safety of the structures.
Detailing is necessary not only for the steel structures but also for the RCC members as it is the translation of all the mathematical expression’s and equation’s results.
DO’S & DONOT’S FOR DETAILING
1. Prepare drawings properly & accurately if possible label each bar and show its shape for clarity
Prepare bar-bending schedule , if necessary.
3. Indicate proper cover-clear cover, nominal cover or effective cover to reinforcement.
4. Decide detailed location of opening/hole and supply adequate details for reinforcements around the openings.
5. Use commonly available size of bars and spirals. For a single structural member the number of different sizes of bars shall be kept minimum.
6. The grade of the steel shall be clearly stated in the drawing.
Deformed bars need not have hooks at their
ends.
8. Show enlarged details at corners, intersections of walls, beams and column joint and at similar situations.
Do’s –COLUMNS.
A reinforced column shall have at least six bars of longitudinal reinforcement for using in transverse helical reinforcement.-for CIRCULAR sections.
A min four bars one at each corner of the column in the case of rectangular sections.
Keep outer dimensions of column constant, as far as possible , for reuse of forms.
Preferably avoid use of 2 grades of vertical bars in the same element.
DONOT’S-GENERAL:
Reinforcement shall not extend across an expansion joint and the break between the sections shall be complete.
Flexural reinforcement preferably shall not be terminated in a tension zone.
DETAILING OF SLABS WITHOUT ANY CUT OR OPENINGS.
The building plan DX-3 shows the slabs in different levels for the purpose of eliminating the inflow of rainwater into the room from the open terrace and also the sunken slab for toilet in first floor.
The building plan DX-A3 is one in which the client asked the architect to provide opening all round.
CONCLUSION:
Before concluding I will show some more details drawn in autocad exported in wwf format
As there is no time to elaborately explaining ,the following topics are not covered :
Flat slabs, Folded plates, shell structures-cylindrical shells, silos,
Staircases- helical staircase, central beam type, cantilever type etc.
Different types of foundations-raft, pile foundation, strap foundation etc.
Retaining wall structures,
Liquid retaining structures.
Deep beams.
Shear wall, walls.
Hope that I have enlighten some of the detailing technique for the most commonly encountered RCC members in buildings.
In the above statements if my senior colleagues and ACCE members can find different method or any new detailing system it will be of immense help not only for me but to other young engineers who should learn in wright ways and not wrong lessons.
[attachment=50612]
WHO IS AN ENGINEER?
According to USA President Herbert Hoover, who was an engineer before he became a politician, said:
The great liability of the engineer …compared to men of other professions……is that his works are out in the open where all can see them.
His acts …..step by step …are in hard substances.
He cannot bury his mistakes in the grave like the DOCTORS.
He cannot argue them into thin air…..or blame the judge…..like the LAWYERS.
He cannot, like the ARCHITECT, cover his figures with trees and vines.
He cannot, like the politicians, screen his shortcomings by blaming his opponents….and hope the people will forget. The ENGINEER simply cannot deny he did it.
If his works do not work……he is damned.
A design engineer’s responsibility should include assuring the structural safety of the design, details, checking shop drawing.
Detailing is as important as design since proper detailing of engineering designs is an essential link in the planning and engineering process as some of the most devasting collapses in history have been caused by defective connections or DETAILING. There are many examples explained in the book" DESIGN AND CONSTRUCTION FAILURES by Dov Kaminetzky.
Detailing is very important not only for the proper execution of the structures but for the safety of the structures.
Detailing is necessary not only for the steel structures but also for the RCC members as it is the translation of all the mathematical expression’s and equation’s results.
DO’S & DONOT’S FOR DETAILING
1. Prepare drawings properly & accurately if possible label each bar and show its shape for clarity
Prepare bar-bending schedule , if necessary.
3. Indicate proper cover-clear cover, nominal cover or effective cover to reinforcement.
4. Decide detailed location of opening/hole and supply adequate details for reinforcements around the openings.
5. Use commonly available size of bars and spirals. For a single structural member the number of different sizes of bars shall be kept minimum.
6. The grade of the steel shall be clearly stated in the drawing.
Deformed bars need not have hooks at their
ends.
8. Show enlarged details at corners, intersections of walls, beams and column joint and at similar situations.
Do’s –COLUMNS.
A reinforced column shall have at least six bars of longitudinal reinforcement for using in transverse helical reinforcement.-for CIRCULAR sections.
A min four bars one at each corner of the column in the case of rectangular sections.
Keep outer dimensions of column constant, as far as possible , for reuse of forms.
Preferably avoid use of 2 grades of vertical bars in the same element.
DONOT’S-GENERAL:
Reinforcement shall not extend across an expansion joint and the break between the sections shall be complete.
Flexural reinforcement preferably shall not be terminated in a tension zone.
DETAILING OF SLABS WITHOUT ANY CUT OR OPENINGS.
The building plan DX-3 shows the slabs in different levels for the purpose of eliminating the inflow of rainwater into the room from the open terrace and also the sunken slab for toilet in first floor.
The building plan DX-A3 is one in which the client asked the architect to provide opening all round.
CONCLUSION:
Before concluding I will show some more details drawn in autocad exported in wwf format
As there is no time to elaborately explaining ,the following topics are not covered :
Flat slabs, Folded plates, shell structures-cylindrical shells, silos,
Staircases- helical staircase, central beam type, cantilever type etc.
Different types of foundations-raft, pile foundation, strap foundation etc.
Retaining wall structures,
Liquid retaining structures.
Deep beams.
Shear wall, walls.
Hope that I have enlighten some of the detailing technique for the most commonly encountered RCC members in buildings.
In the above statements if my senior colleagues and ACCE members can find different method or any new detailing system it will be of immense help not only for me but to other young engineers who should learn in wright ways and not wrong lessons.