www.sefindia.org

STRUCTURAL ENGINEERING FORUM OF INDIA [SEFI]

 Forum SubscriptionsSubscriptions DigestDigest Preferences   FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups  RegisterRegister FAQSecurity Tips FAQDonate
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log in to websiteLog in to websiteLog in to websiteLog in to forum 
Warning: Make sure you scan the downloaded attachment with updated antivirus tools  before opening them. They may contain viruses.
Use online scanners
here and here to upload downloaded attachment to check for safety.

solution for undulation of flooring in ground Floor

 
Post new topicReply to topic    www.sefindia.org Forum Index -> Freshers' Zone
View previous topic :: View next topic  
Author Message
Rajeev Mishra
SEFI Member
SEFI Member


Joined: 06 Dec 2009
Posts: 17

PostPosted: Tue Feb 04, 2014 10:35 am    Post subject: solution for undulation of flooring in ground Floor Reply with quote

There is a problem in case of framed structure if a colony is constructed in Black Cotton soil having different slope. Generally plinth beam is casted 1.5 to 2.00 M above top of footing. Now what is the CHEAPEST way to do flooring i ground floor.
1. Simple flooring without any treatment below plinth beam.( In this case problem is that after some time Undulations occurred in floor as black cotton soil below floor goes out anywhere .)
SOLUTION - What is Cheapest solution- (I) I saw a building where they are casting RCC slab over PCC at ground level. I think it is costliest one . (II)Another solution is that prepare BOX by closing outer wall ( In a depth from bottom of plinth beam to lowest level of footing.) by brick masonry.(III) Do construct a basement but it is costly.
A request from all Engineers to suggest any other solution or comment in methods written above.
Rajeev Mishra
Back to top
View user's profile Send private message
balki16
...
...


Joined: 04 Nov 2012
Posts: 111

PostPosted: Thu Feb 06, 2014 8:54 am    Post subject: Reply with quote

Dear Sir

In the outer walls the beam should be be provided at 150 MM below the ground level (Grade Beam) so that wall can be constructed over the  grade beam to retain earth.

If black cotten soil is to be used for filfling it should be ensured that no water flows in to the plinth. (Bit difficult). Better used a better soil for filling under plinth.

Regards

K. B.
Back to top
View user's profile Send private message
Rajeev Mishra
SEFI Member
SEFI Member


Joined: 06 Dec 2009
Posts: 17

PostPosted: Thu Feb 06, 2014 9:18 am    Post subject: solution for undulation of flooring in ground Floor Reply with quote

I thank you for your valuable suggestions. Actually changes in the behavior of black cotton soil is occurred ,normally, up to 6' below GL. Hence level of grade beam should be around top of the footing 7 then plinth beam. A request from all engineers to comment. Rajeev Mishra.  
Back to top
View user's profile Send private message
umeshrao
...
...


Joined: 23 Aug 2010
Posts: 573
Location: Bangalore, India

PostPosted: Fri Feb 14, 2014 10:51 am    Post subject: Re: solution for undulation of flooring in ground Floor Reply with quote

Rajeev Mishra wrote:
I thank you for your valuable suggestions. Actually changes in the behavior of black cotton soil is occurred ,normally, up to 6' below GL. Hence level of grade beam should be around top of the footing 7 then plinth beam. A request from all engineers to comment. Rajeev Mishra.  


Dear Mr. Rajeev Mishra,  

Restricting myself to the flooring and not to others aspects mentioned in your mail, I think foremost thing take care of swelling of black cotton soil.
Hence, remove BC atleast upto 400 mm from natural ground level and do not use this soil as back fill. Fill this by any other soil containing about 60 to 70 % sand right upto bottom of PCC supporting floor finish. That is almost 400 + 300 = 700 mm of soil. One possible way is providing soling which has voids in rubble so that soil when expands can get into voids and not exert pressure on grade slab. Mixing lime in 1: 4 proportion is common practice to stabilize swelling soil.
If not provide structural slab connected to beams provided at plinth level and design for uplift due to swelling pressure.
Reducing cost keeping performance criteria is consider as economics.
Regards
Umesh Rao
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topicReply to topic    www.sefindia.org Forum Index -> Freshers' Zone All times are GMT
Page 1 of 1

 

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


© 2003, 2008 SEFINDIA, Indian Domain Registration
Publishing or acceptance of an advertisement is neither a guarantee nor endorsement of the advertiser's product or service. advertisement policy