Need advice from expert in concrete construction methods. Can anyone help?

I'm a volunteer trying to build a house for several very poor families in Cambodia. Wood and rebar are very expensive! I have a small budget and am stuck. I have set 16 concrete pillars in a concrete footing. I have built the walls with brick. At the top of the pillars I have poured cross beams connecting all the pillars together. I want to know if Ican pour a concrete slab on top of the pillars using #12 rebar set at 1/2 meters apart forming a mesh on top of the pillars and then pour 10 cm (4 inches) of concrete mixed 3-8-10? Will this work? There will be a second story with a lightweight tin roof. No heavy appliances or furniture. Can someome please advise me.Need advice from expert in concrete construction methods. Can anyone help?
whats the span in between pillars,,,whats the floor area ,,,sounds for sure itwill work if its realatively small , modern buildings, are built with poured concrete floors that make up the cieling for the floor below you need lots of removable support while you are waiting for it to cure and while pouring under the floor ,cieling ,support through the area and around the perimeter to carry all the concrete weight for at least 72 hrs ,,, im really not an expert in civil


engineering but a small area should be easy you may need permanant support for a larger area there should be info online for permanant support you may be able to look at sq ft area spans in another buildings plans or just by looking ,,,,you can't expect them NEVER to put heavier stuff up there either some day they may start a rock collection ; )Need advice from expert in concrete construction methods. Can anyone help?
I don't know what resources are available. Concrete ceilings are tricky, to form - need lots of later removable supports till concrete sets (several days min). Sounds like you application really does not need 4' thickness. I've poured as thin as 2'; but I was sure to add fiber reinforcing into the mix.