THE RAISING OF A SUPERMARKET FLOOR OUTSIDE OPENING HOURS
The supermarket in question had been operating in Zhenjiang, China, for 3 years. The structure is supported by pillars placed into the bedrock and the floor slabs of the building are attached to the pillars. During the 3 years of operation, subsidence problems had occurred, causing problems, in particular, with shopping trolleys that were able to roll free and uneven product shelves. One of the basic expectations of customers and employees in a grocery store is a safe shopping environment. Uneven floor surfaces may result in unexpected dangers, such as sprained ankles or even bumps on the head.
The owner of the property was presented with two alternatives to fix the problem- either remove the entire floor and build a new one (resulting in a closure of the building for at
least 3 months) or choose the URETEK re-levelling solution (with the supermarket continuing its normal business operations, whilst the remediation work was carried out). URETEK was contracted to lift an area of 4700m² between -80mm and -170mm.
The aim of the project was to lift the floor slabs so that the supermarket could operate normally without having to worry about hazards caused to employees and customers by rolling customer carts and unlevel product shelves. Another important aspect was that the remediation work shouldn’t affect the operating hours of the supermarket, which meant, that the work would be performed during the night. The schedule was tight, as the Chinese New Year was approaching and the work needed to be completed before that.
Geopolymer injections were used, as these are an optimum solution to lift floors that have subsided.
Holes 12mm in diameter were drilled through the 200-300mm thick concrete slabs at 1-3meters intervals. The geopolymer was injected through the holes. When the geopolymer is injected, it expands under the floor slabs, filling the voids and compacting the ground. The eventual result is a lifting of the floor slabs. The URETEK team worked outside the store’s opening hours and a total area of 4700 m² was lifted over 41 days. The project did not affect the customers or the business of the supermarket. The property owners and the supermarket were very satisfied with the results of the lifting, along with the non-disruptive process and the tight schedule with which it was delivered.
“For us, it was most important to keep the effect on our daily business, caused by the floor repair works, as low as possible and not to compromise on our opening hours. The store remained open during the project, without interruption. The project was also completed within the agreed upon schedule and we are very satisfied with the results and how URETEK carried out the work.”
- Michael Neundorf, head of construction of Metro China