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groszni awesome

Tie beams design

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assalamualaikum sepakistan, i wanna ask how do you design properly the tie beam? i always use the moment from base column (fixed base support) to design the properties (geometri and steel reinforcement) and its the same value of steel along the beam (from the support to middle and to support again). theres also a 10% of gravity of column additionaly as a axial load on the beam. so i use an interaction diagram just like design the column. because the moment of base already got taken by the tie beam then i never consider moment anymore when design the footing. Am i doing it right? please correct me if im wrong and additional question is whats the difference between the tie beam, ground beam, grade beam and plinth beam?

thank you

regards :)

Edited by groszni awesome

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Tell me why are you not designing it using software to take care of all the forces for design?

More over in my opinion, tie beam grade beam ground beam and plinth beam are not different necessarily. They are just terms to define the type of beam. Tie beam is a beam used to tie two columns for two movememts. Vertically and horizontaly by increasing stiffness of structure there. For example column A and column B are tied.if column B settles, the tie beam will offer a resistance to its settlement by transfering force to column A. Also if column B moves horizontaly, tie beam will tie column B with column A and hence offering a frame actiom to reduce horizontal deflectiom. Tie beams may be at any level. If these are at plinth evel they are called plinth beams where it also helps in soil retaining of inner house area and offer also as support for walls. Plinth beams my also be designed as tie beams or just as plinth beams to support walls etc. Grade beam is a beam cast against earth. If below plinth there is not brick foundation and plinth is supporting wall then this plinth beam also called as grade beam. And grade beam and ground beam is same. 

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Engr Waqas has replied you well. Beams are beams and columns are columns. Do your structural analysis and design them for forces they will experience. Don't reduce any forces thinking that these beams are tie or plinth. Plus stop tagging people in your posts. That is very unprofessional.

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The  design of tie beam will be governed by amount of differential settlement of the foundation selected for the job at hand.

If delta is the differential settlement, then the fixed-end moment due to that value will be: (6EI/L*L)delta. Add the gravity load Fixed End Moment to it, and then distribute this moment among members of beam-column joint according to their flexural stiffness.

That is a crude way of proportioning the tie beam.

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7 hours ago, BAZ said:

The  design of tie beam will be governed by amount of differential settlement of the foundation selected for the job at hand.

If delta is the differential settlement, then the fixed-end moment due to that value will be: (6EI/L*L)delta. Add the gravity load Fixed End Moment to it, and then distribute this moment among members of beam-column joint according to their flexural stiffness.

That is a crude way of proportioning the tie beam.

Differential settlement consideration for tie-beam is a good design practice. Good point.

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On 12/30/2016 at 8:53 PM, Ayesha said:

Engr Waqas has replied you well. Beams are beams and columns are columns. Do your structural analysis and design them for forces they will experience. Don't reduce any forces thinking that these beams are tie or plinth. Plus stop tagging people in your posts. That is very unprofessional.

what do you mean its very unproessional? why did they add a such option if we cant use it? i just need some help and some opinion from them because they are like the most active users in this forum sorry i get offended 

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