CapsLock

the dark part is the area where light doesnt pass as the sun sets ,

Do not make it to close you may make for yourself a Jacob's Ladder!

3 cores or 1 core cables? Laid in cable trench or on cable ladder ? How many cables in parallel,How many layers of cables on top of each other,for multiple circuits ? At least provide these imformation when you want a proper answer.

Anyway,technically,the 11kv straight through joints can be as close to each other as you like.For practical reasons, keep some spacing between a joint and the next cable because when there is a cable joint failure,the adjacent good cable will less likely to be affected or damaged. If you are cutting a single cable to repair it or to loop-in and loop-out the 11kv supply in a ring circuit, these 2 joints should be about 10 metres apart.This will provide enough cable run for bending radius requirement.The joint itself should not be in the bend or in GI pipe.Except for resin filled type of joints,the joint section is the weakest part of the cable.

Regards,

Khor

You have provided so little information. Is this for a toy Jacobs ladder or an overhead 11kV transmission line?

For anything other than a toy or home project please consult your local electrical standards as the information is clearly stated in there for your specific application along with any other requirements that need to be met.