Geopolymers are widely used for restoration and repair of production and industrial buildings. Geopolymer resins are suitable for reinforcement of foundations, as for buildings that are being used by the company, so for buildings that are presently not in use and are being modernised for installation of more powerful equipment.
Rimi shopping centre in Ventspils was erected on a marshy soil, which caused floor subsidence and the owner of the centre contacted URETEK Baltic OÜ, asking to find a solution to the problem.
Total area to be compacted, lifted and re-levelled was 4,500 square metres. Another challenge besides geodetic issues consisted in the fact that URETEK team could only work outside opening hours, i.e. at night. It was not possible to move the shelves, all goods were covered, and works had to be finished by the time the store opened. However, one thousand out of 4,500 square metres, consisted in storage area, where work continued at night as well, so it was rather challenging to find a suitable window for performing the injection. An area of 500 square metres consisted in general corridors with escalators, which was the only access to the second floor. Therefore, works were planned and timed with utmost precision.
URETEK Baltic OÜ completed the task successfully, there was no need to close the shopping centre for carrying out works and shoppers did not even notice that the centre was undergoing repairs.
FEB logistics centre is the heart of the company, which operates 24h a day. Even brief stoppage of work of the centre would be very challenging and costly for the company. However, floors of the warehouse had to be lifted and soil under the floor compacted, because concrete slabs had started to move under the weight of forklifts.
URETEK performed inspections to ascertain that loads created extremely strong pressures in the vicinity of expansion joints. At first, it was urgent to restore the substrate of concrete slabs in order to avoid their breakage. It was impossible to use any solution that required stopping work, as it would have been too costly. It took six hours to stabilise 150 square metres of floor area without encountering any problems or disturbing the ordinary operation of warehouse. URETEK floor lifting technology SLAB LIFT allowed filling the voids under the floor with patented expanding geopolymer, which is specifically designed for this type of work.
Expanding geopolymer strengthened subsoil and restored contact between floor and underfloor. Work performance was measured by laser level, which registers lift at the accuracy of 0.5 mm. In order to minimise any disturbance to the client, URETEK team carried out works by sections. Total time spent on works was six hours and the first fully loaded forklift was allowed in the area already 10 minutes after completion of works.
In a shopping centre in Vilnius occurred floor subsidence, affecting 3,500 square metres of floor and three concrete support posts. Subsidence was caused by construction fault that had not taken into account peat layer under the centre at the depth of 4—5 m. In fear of repeating the tragedy of Maxima store in Riga, the shopping centre was immediately closed, obviously causing great financial loss for the owner.
Concrete posts were supported by building contractor under the guarantee, but in order to lift the floor, the owner of the centre contacted URETEK team. It represented a major challenge, because the difference of floor heights reached up to 25 cm.
Shopping centre was closed for repair for nearly six months, but without using URETEK technology, reopening of the centre would have been delayed even longer, causing even greater loss for the owner.
URETEK was contacted by a shopping centre with a long history the city of Tartu, whose main tenant is Prisma – a beloved supermarket among the residents of Tartu. Considering the building conditions, the shopping centre was built on complicated soil and due to that the parts of the supermarket floors which had to bear heavier inventories and goods had started to sink. Fortunately, an inspection revealed that the sinking was only in the floors and the load-bearing structures were intact and without any damages. The area of the floor that had sunk in the warehouse and in the sales hall of Tartu Prisma was 500 m2 and 600 m2 respectively. Since the daily activities of Prisma could not be interrupted, the necessary works in the warehouse were performed in four consecutive nights and the works in the sales area in three consecutive nights without closing the shop for customers. This allowed the customers to maintain their daily rhythm during the repair works and did not entail any additional costs.
Within the repair works, the soil underneath the floor was stabilised with URETEK technology. This included drilling holes with only 14 mm diameter to the floor in order to perform the injection. The method allows to avoid large-scale and noisy construction works and, what is especially important in food industry, works which create dust.
The other but not less important benefit of the method of URETEK is the fact that this technology allows to carry out large-scale renovation works without disturbing the customers and closing down the shop, which is especially crucial for shopping centres because it is known that closing a shop for two weeks may lead to a decrease in turnover, the recovery from which may take up to six months.
Over the years, acidic silage effluent had caused leaks in concrete gutters of the silo and silage effluent seeped from the silo to soil, eroding the soil beneath concrete slabs and polluting adjacent field. Silo had already been repaired two or three times, but to no avail, and the company eventually contacted URETEK team.
URETEK technology was used to first fill the voids and restore the load-bearing capacity of soil. Then geopolymer was injected behind the gutters to stop the leaks.
This work took 4 hours, whereas in case of using traditional method, cutting out concrete slab would have increased the cost of work three times. In terms of time, such a job would have taken approximately 2—3 weeks.
Floor of the milking parlour is daily washed with plenty of water. In this case, it caused subsidence of concrete floor, directing animal faeces and wash water away from drain traps and making it very difficult to keep the floor clean.
URETEK technology was used primarily to stabilise the soil under the floor and to restore its load-bearing capacity. Then concrete slabs were re-levelled. For that, slabs next to the wall were lifted by 8–15 cm, respectively.
Such job would not have been possible when using traditional method, because the interval between two milking sessions is 4 hours and it cannot be changed. Thus, URETEK was ready to complete works in two four-hour cycles.
In the course of construction of new repair workshop, the soil under the foundation remained uncompacted at one end of the building, and construction works had to be stopped. The extent of subsidence exceeded permitted tolerance limits many times and the structure became unsafe due to risk of collapse. Inspection revealed that there was one metre thick peat layer in the soil under the foundation.
By using URETEK technology, special geopolymer was injected in the soil, which expanded and forced peat out, taking its place. Geopolymer injection restored load-bearing capacity of soil. Lifting was not performed because URETEK team and client did not consider it to be practical.
By choosing URETEK technology, the client primarily saved time. Construction works had been discontinued for a month already and client lost time and money while looking for a solution to the problem.
Subsidence of a lead-bearing structural post caused by leaking drainage pipes was discovered in a factory in Latvia. Load-bearing capacity of soil was insufficient up to the depth of 2.5—4.2 metres, as the leakage had carried the soil away. As a result of that, structural post and foundation had sunken by 5 cm and further subsidence was only a matter of time.
URETEK technology helped to stabilise the subsoil under the post, restore load-bearing capacity and re-level the post by 1.5 cm. Further lifting was not possible, because that would have damaged load-bearing structure. Therefore, in cooperation with the client, it was decided to lift it by only 1.5 cm.
Work lasted for 6 hours. In case of using traditional method, this problem could not have been solved without stopping the operation of the factory. It is difficult to estimate time and money saved by the client.
Due to poor compaction, the soil under reinforced slab had sunken to large extent and up to 4 cm subsidence had occurred between skirting and parquet flooring.
URETEK technology was used to stabilise the soil under the ground floor of the building and to lift the floor to its original position. Traditional method would have required moving everything out from the offices, removing existing laminated parquet flooring, re-levelling joists supporting the OSB board above reinforced concrete slab and then reinstalling the parquet flooring.
URETEK completed the job in five hours and there was no need for any additional works.
