In case if concrete box girder bridges how is the number of cells determined?

Thanks for your invitattion

i thing this is repeated quision

Athough this not in my specialist and after i read: 

But the princible to carry the wieght load from a point inidefference as to whether the pending moment in positive and negative forc to there torsional stafness from the point of view of economy.

When the depth of a box girder bridge exceed 1/6th or 1/5th of the bridge width then the design recommended is that of a single cell box girder bridge. But in case the depth of the bridge is lower than 1/6th of the bridge width then a twin-cell or in some cases multiple cell is the preferred choice. One should also note that even in the cases of wider bridges where there depths are comparatively low the number of cells should be minimized. This is so as there is noticeably not much improvement in the transverse load distribution when the number of cells of the box girder is higher than three or more.

thanks for the invitation

I agree with the answer colleague Eng / hisham abu dagga

When the depth of a box girder bridge exceed 1/6th or 1/5th of the bridge width then the design recommended is that of a single cell box girder bridge. But in case the depth of the bridge is lower than 1/6th of the bridge width then a twin-cell or in some cases multiple cell is the preferred choice. One should also note that even in the cases of wider bridges where there depths are comparatively low the number of cells should be minimized. This is so as there is noticeably not much improvement in the transverse load distribution when the number of cells of the box girder is higher than three or more.

Thanks for your invitattion

i thing this is repeated quision

Athough this not in my specialist and after i read: 

But the princible to carry the wieght load from a point inidefference as to whether the pending moment in positive and negative forc to there torsional stafness from the point of view of economy.