Block Paving Storage Area

[Zambo]

We are designing a block paving storage area. The existing ground is reclaimed land which is sand 6m deep with underlying silt.

The requirement is for a storage area which will hold fabricated units up to 100 tonne and containers. Axle loads are generally 10 tonne per axle, but the heaviest loadings may be those from top loading forklifts carrying 40 foot containers.

The plan is to excavate to formation in the existing sand, compact and then lay an unreinforced concrete slab. Block pavers will be laid on a 50mm coarse sand bed.

Any recommendations on the slab thickness? or advice in general on the proposal?

 

[dik]

Can you provide me with the dimensions for the wheel pattern and the wheel loads and bearing area of the wheels?

Dik

 

[concretemasonry]

This is not a typical design for interlocking concrete pavers. The usual applications are for 80 to 100 mm thick pavers and to place them on a 4 cm sand setting bed on a copactated soil base. This is commonly done for airport taxiways and container ship unloading facilities throughout the Indian subcontinent east to the major Pacific ports. The use of any concrete under interlocking pavers is normally discouraged unless there are specific soil conditions.

There are many fine examples in India, Maylasia and othe countries with high capacity ports.

The ICPI (Interlocking Concrete Paver Institute) and several European organizations have very good design guides for heavily loaded applications on marginal/moist soil conditions.

 

[Zambo]

Dik, thanks but that is a bit complicated for now all the information I have is 10 tonne per axle and in addition to my earlier post 130tonne (approx 1300KN) on a 16m2 footprint.

concretemasonary, I have seen a port carried out as you say with concrete blocks laid on sand on a compacted crushed rock sub-base - this was Fishguard (spelling?) in Wales. I have also worked on a Port in West Africa where we used concrete blocks on sand on a cement stabilised sub-base. I think it is not unusual to use CSM or concrete for this purpose.

 

[dik]

I'm not familiar with the type of construction except for use for hangar aprons and taxiways. I'd just assumed that due to the high concentrated point loads of the fork lifts that Zambo was planning to use a concrete base. Concrete is often not used in some areas because of the lack of good aggregates, etc.

In the absence of a solid base, I've used non-woven geotextile to provide a more stabilized base. I've also used lime with some clay materials.

Dik

 

[Zambo]

concretemasonary, I have visited the website and downloaded the info. I am thinking about subbase of 300mm crushed rock, roadbase of 300mm thick lean concrete, 50mm sand bedding with 100mm thick concrete blocks. I was also considering a geotextile between the sand subgrade and the crushed rock subbase.

 

[concretemasonry]

Zambo -

The choice of a 100 mm paver is good. If available locally, the "zig-zag" paver shape usually is better than the rectangular brick shape. Also, the "herringbone" pattern gives better stability, especially if you have repeated turning traffic patterns.

You may want to check with the local suppliers about shape availability. Also your area may or may not use more automated setting equipment. The large Asia projects for ship containers I have seen were usually hand set.

Dick

 

[vieiraemoreira]

Does anyone has a little program to calculate rigid pavements?

I've got Elsym5 to calculate flexible pavements, however to calculate rigid pavements I need a program or a excel file.

 

[dik]

vieir...: I've got a couple, one based on AASHTO and the other published by the FAA for aircraft pavements. I also use a program prepared by the PCA for Aircraft pavement design.

Dik

 

[vieiraemoreira]

Hi Dik:

Thank you for the answer. I've got to design a industrial pavement road that will be loaded with heavy traffic.

Do you think the PCA program can help me to solve the problem?

Vieira e Moreira

 

[dik]

Not directly... I'd use it to help formulate a guess <G>.

There are several layered pavement programs available, but, I haven't used them. I have an excellent mathematical analysis listing that's a little 'hairy' and haven't had an opportunity to code it into Delphi... I can try to dig up link if you like.

Dik

 

[vieiraemoreira]

do you know where can I download some of the programs? I think there's one called "kenslabs", that's in the Huang's book (Pavements analysis and design) that could work in this case.

However if you can help me with your math analysis I'd enjoy.

vieira e moreira