Making cement

[westbounder]

Hi,
I am building a 3 meter by 17 meter rear covered porch at rear of house.
I can not get a cement truck to the area I need to make the porch.
Is there a way to make the concrete on the premises without buying from a cement truck?
I think I have possibly seen people in the past do it this way but I am not 100% sure.

Thank You...

[jvs]

You will need 5.1 cubic meter of cement.Say 6 just to be sure this is 6000 liters.

one portland two sand three gravel.=1000 portland 2000 sand 3000 gravel all in litres.

Any Thai contractor can mix this amount by hand in a day,more easy if they use a mixer.

Make sure there is enough run off and use mesh under the concrete.Also make sure you put in any pipes

for electric or water before you pour.

Another way is to get lots of guys with wheelbarrows and bring in the mix from the truck,you may have to pay a little extra because of the time it takes.

I always put plastic under the cement,this keeps it from drying out too fast .

[westbounder]

Thank You

[Dante99]

Making is to site is certainly possible by hand or with a mixer.  

It also may be possible to hire one of those crain like trucks that have a long boom and could reach to the pour site, like they use to get the ready mix from the truck up to second and third floors.   Building contractors use them often and perhaps some of the ready mix companies can provide them.  Of course depends on how close they can get to your pour site.

[stubuzz]

Mixing by hand is not advised:  get a mixer.

[hmficc]

You want to make concrete. Cement is one ingredient.

[Dante99]

10 hours ago, stubuzz said:

Mixing by hand is not advised:  get a mixer.

It is not the mixing that is the problem, it is the measuring which applies to both methods.

[vogie]

Its very hard work mixing by hand and I'm not too sure about the mixes here. I generally use a 1 2 4 mix (1 cement, 2 sand and 4 stone) but the mixes are very stoney so I tend to add more sand and cement till the mix becomes more workable. Maybe the sand is not good quality? Never had any problems in the UK with mixes.

[KhonKaenKowboy]

You will need several expansion joints.  Also,the trucks have long extension hoses in some cases.

[canuckamuck]

Your sand to gravel ratio is dependant upon the quality of the sand. Up where I am I can get river sand very cheap but the sand contains very little fine sand and lots of coarse (3-5mm). So I need to treat the river sand more like gravel than sand. Hence I also have to bring in some fine sand to make nice cement which doesn't begin to erode in a year.

Generally I am using one fine sand, two coarse sand, and three gravel to 1.5 cement. It is probably more cement than others use, but after trial and error it has been working for me

 

Also, you need to get a mixer. I have a smaller mixer (10,000 baht) which makes a wheel barrow full of concrete in about three to four minutes) so I can basically keep up with one guy running cement and another guy troweling without making them wait. But you also need a guy feeding material.

 

The Thai guys won't use my mixer, because they are used to making mixes based on one full bag of cement at a time and they prefer to use a bigger mixer or to do it by hand with a hoe. You will find that unless you get a very experienced guy, the hand mixes will be all over the board when it comes to ratio. A common practice is to have a pile of premixed dry material with a crater in the middle in which they pour water and mix in the material.  just adding in more dry as needed. the problem is that they lose track of the ratio almost immediately  and go by sight the rest of the day. which is why my workshop has a nice hard floor in most places and a crumbly dished out area in the middle, where the guys were bringing out concrete with hardly any cement in it.

[vogie]

How much is a sq meter of concrete delivered and they charge more for part loads?

[billd766]

5 hours ago, vogie said:

How much is a sq meter of concrete delivered and they charge more for part loads?

 

Actually it is measured in cubic metres (length x width x height).

 

Out here in rural Khampaeng Phet last year it was 1,550 thb per cu/mt and the truck held 5 cu/mt per full load.

[jvs]

7 hours ago, KhonKaenKowboy said:

You will need several expansion joints.  Also,the trucks have long extension hoses in some cases.

There are no hoses unless you order a cement/concrete pump and that is not advisable for a small job like this.

 

[jobin]

Could OP not hire laborers with wheelbarrows to haul the ready-mix from the street to the site? I'd say 3 guys, muscular and young, would do the job in 3 hours. That's just toting and dumping. Other workers needed to tamp, smooth etc.  Of course, the OP needs to sitting in a high chair overseeing  and directing operations.

[vogie]

10 minutes ago, jobin said:

Could OP not hire laborers with wheelbarrows to haul the ready-mix from the street to the site? I'd say 3 guys, muscular and young, would do the job in 3 hours. That's just toting and dumping. Other workers needed to tamp, smooth etc.  Of course, the OP needs to sitting in a high chair overseeing  and directing operations.

 

With the heat in Thailand I would like to take less than 3 hours to move the concrete.

Edited October 14, 2016 by vogie

[jobin]

Deliver 5 am and use ice, not water to mix !

[vogie]

7 minutes ago, jobin said:

Deliver 5 am and use ice, not water to mix !

 

Taken from the internet:-

 

How long can concrete remain in the delivery truck before its no good?
The recommended time from when concrete is batched until it is considered "no good" is 2 hours, when the temperature is between 60 F and 80 F. If the temperature is lower, it may take a little longer for the concrete to begin accelerated hardening. When the temperature is higher, it is wise to monitor the concrete temperature, and if it rises above 90 F, discard the balance of the load.

 

I personally would not risk it, but as they say "up to you"

[jvs]

Really?Adding sugar can extend the life of the mortar.I would not really worry too much about this,

the op is pouring a simple porch floor,not building a skyscraper.