Ted,
This is from an article I read about Goodyear's recommendations some time ago.
Storing Tires On the Vehicle
RV tires are mostly stored on the vehicle. For ideal storage, a vehicle should be placed on blocks so there is no weight on the tires. If this cannot be done, follow these tips for best tire protection:
- Unload the vehicle to reduce weight on the tires to a minimum.
- Wash the tires with soap and warm water; dry completely before storing and especially before covering the tires.
- Ensure that tires are inflated to the recommended operating pressure. (Goodyear recommends going over by 25% provided this does not exceed the maximum.)
- Check pressure every two or three months, and again before the vehicle is returned to service.
- If the vehicle cannot be blocked up, store it on a surface that is firm, clean (no oil, grease, or moisture), well-drained and level.
- Move the vehicle quarterly (except during very cold weather) to prevent flat-spotting (prolonged strain of sidewall and tread deflection) and ozone checking in the bulge area.
- If the vehicle is stored outdoors, use tire covers to reduce UV damage.
Proper storage can add to tire life by helping the rubber resist the effects of UV light, ozone, moisture, exposure to oil and grease, and deformation of the tread and sidewall. An occasional half-hour of care can both add extra traveling distance and reduce the chance of future problems.
I figure that since you are using it during the time it's in "storage" you'll be fine on the cement. Especially since you'll have weight off the tires when you level up.
Wes