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[A B Malla]

Dear Sefians,

I would like to know the difference in Permissible Stresses of Bolts considered in Table 8.1 of IS:800-1984 & Table 1 of IS 802 ( Part l/Set 2 ) : 1992, since both these tables show different values. kindly share your expertise.

PFA Tables for reference.


Regards,
A. B Malla

[Dr. N. Subramanian]

Dear Er Malla

IS 800:1984 is in Working stress format(we have to now use IS 800:2007 only) and IS 802 table shows ultimate stress. Hence the difference. It is better now to use the values given in IS 800:2007

Best wishes
NS

[A B Malla]

Dear sir,

it is as per contract requirement to use IS 800 :1984, since the project is old & is still going.

1. IS 802:1992, it is observed permissible shear stress in 4.6 grade bolts is 218 Mpa, while for same grade of bolt permissible stress is 80 Mpa in IS 800:1984.

2. I presume both IS 800 & 802 are working stress please clarify.

3. while designing bolts for tower, which stress is to be considered.
(In Transmission line structures by S.S Muthy & A.R Santhakumar, IS:800:1984 table is mentioned).

i'm delighted to see the reply is coming from author of the book, which i was referring to in my UG & PG . Thanks to SEFI.

Regards A.B Malla

[Dr. N. Subramanian]

Dear Er Malla,

Please note that while IS 800:1984 is based on working stress method, IS 802: 1995 is based on Ultimate load concept- See Back of Front Cover of IS 802(Part 1/Sec 1): 1995. Hence there should not be any confusion, though it is not stated clearly in IS 802(Part 1/Sec 2) of the code.

Perhaps this code (IS 802) will also be revised based on IS 800:2007 soon.

Good to know that you referred my book in UG and PG. All the best.

Regards,
NS

[A B Malla]

Dear N S Sir,

Thank you very much for your valuable time from your busy schedule. Such efforts from your side benefits all of us.


Regards,
A B Malla