Advice required - Circular block/brick border

[sublime]

Hi ive been a regular visitor to the site for a few years now for helpful tips. Im general do it myself type with a mixture of 10 years worth of ground works and joinery exp. I now work for myself along with my younger brother.

My latest project involves a 1.5 metre radius/ 3 metre circle to be made using block paving or brick with an infill of topsoil and turf. The customer is asking for a rustic look so Im not to bothered about gaps as I understand anything less than a 2m radius would be best to cut the block/bricks. She would like the border to be 3 bricks wide.

Im going to lay them on a compacted type 1 and haunched bed of mortar base and point them. Possibly concrete bed? Just cost effective the usual!!

Was wondering what the quickest most accurate method of calculating how many block required, unfortunately the brick size has not been established yet.

Any advice would be great.

Thanks for having me!

[lutonlagerlout]

the circumference of a circle is
2 PI R*

so 3.142 times 2 = 6.284 times 1.5m =9.426

9.5 divided by .200 = 47.13

so as each course gets slightly bigger I would allow 155 blocks

cheers LLL

[sublime]

thanks, how the hell did I get 278? I calculated the linear meterage as 9.5m divided that by .113 to allow for a 13mm gap x by 3 and allowed for breakage.

pfft I was way off!

:p

[sublime]

ahh I went with 100mm blocks lol a different size