Any building joints 2

[curiousinvite]

This building is going to be constructed on a high earthquake prone area, since the two building are close to each other there is fear of hammering between two building during earthquake . Are there any joints we can make to prevent it?

 

[SJBombero]

The buildings must be separated sufficiently to preclude pounding. If this is in the US, ASCE 7-16 requires a seismic gap of the sum of the squares of the inelastic drifts of each building. Seismic gaps are then covered with special joint covers that allow movement but seal the gap. One thing that is often overlooked is the sealing material in these seismic joints. The width of the seismic gap should be detailed such that including the hardware of the joint and the compressed sealing material, your minimum net gap is what you have calculated above.

If you google "Seismic Joints" you will find sufficient pictures to give you an idea of what needs to happen. Engineers typically don't specify a joint, just the minimum net gap required.

 

[HTURKAK]

I do not know the applicable code at your region .. But apparently, the length of bldg 50 ft and width around 14 ft and does not justify for providing seismic separation and doubling the columns..

The following is excerpt from ASCE 7-16 for Structural Separation requirement;

(12.12.3 Structural Separation. All portions of the structure shall be designed and constructed to act as an integral unit in
resisting seismic forces unless separated structurally by a distance sufficient to avoid damaging contact as set forth in this section. Separations shall allow for the maximum inelastic response displacement (δM)...)

You may provide more info. to get better responds..

 

[MotorCity]

Unless the two building sections are drastically different in height or period, (or if there is thermal expansion), the use of a seismic separation joint is not justified in my opinion.

 

[SJBombero]

The separation of the buildings may not have engineering justification but it could very well have legal justification.

 

[curiousinvite]

Thanks for reply , One more question ,isolated footings are provided for these adjacent columns(circle ), I was thinking it would be better provide combined footing . Any suggestions?

 

[HTURKAK]

Yes .. you shall provide combined footing for those adjacent columns ..

Will you post the proposed foundation plan showing the tie beams ? What is the reason for the EJ ?.. Still i am not convinced..