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Bikki

Isolated Footing at different levels

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Thank you for the reply..

To make things further clear....

Do we have to design  the building accordingly or Adopt depth as per site conditions??

For example, Say footing depth  in a building is designed as 1.5 m below ground level. But on site,  one of the footing lies in a depressed zone, so footing depth won't be 1.5 m in that footing. What should i do in such case?? DO  I go deeper in that one particular footing OR Compromise on the footing depth OR Go deeper in rest of the footings to match the depth in that particular footing?? 

Edited by Bikki

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If there is difference in NSL on site change the foundation level as per NSL , Place your foundation at competent soil strata(hard soil, having no organic material or loose patches). you can make foundation in steps as well, go deeper for the depressed zone. there might be more appropriate answer if you share a sketch of your building and its foundation, contours etc. information of building will help to understand the problem more accurately.

Regards

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Thank you.

Here is a illustrative drawing>>

So, then we have to provide tie beam as in picture. Am i correct?

Which is more appropriate? providing footing as in picture Or Levelling the whole site to match the lower footing level??

 

dd.jpg

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as i scale the distance between the two footings it seems 2.00, it ensure the upper foundation load will not intersect the lower foundation directly(45 degrees rule), place the footing in steps as you described. if you are excavating by  excavator it would be difficult to maintain the level during excavation, if it is manual excavation it will be feasible, provide tie beam it will improve the load distribution. these are my perceptions, i request to others please comment .

regards

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