concrete slabs | URETEK

Lifting and stabilisation of port facilities

Geopolymers do not react with water, they remain stable even in humid environment. This allows using geopolymers for levelling and strengthening of jetties, embankments and berths.

URETEK geopolymer resins are suitable for stabilising infrastructure objects of seaports and river ports. In order to lift concrete structures and stabilise them, geopolymers can be injected under the concrete slabs of jetties, embankments and berths as well as in water-saturated subsoil of these structures.

Strengthening the soil under jetties, embankments and berths

Construction of concrete jetties and embankments generally requires installation of a vertical support wall that would retain filling material necessary for installing concrete slabs. Due to constant water influences, surface water level changes dynamically, meaning that there are also changes in the moisture content of soil under the structure.

As a result of that, filling material can slowly become more compact and horizontal surfaces are subject to movement and uneven subsidence. Concrete slabs of jetties, embankments and berths are also affected by heavy duty vehicles, gantry crane, transporters, loaders and other additional loads. Total weight of port loader with transmission container reaches up to 100 tons. Naturally, such weight causes increased compaction of the filling material under concrete base and soil under the entire structure. Thus, different sections of concrete surface may suffer from uneven subsidence.

In order to level concrete slabs and stabilise the structure of jetties, embankments and berths, filling material and subsoil of the structures must be strengthened. Load-bearing capacity of soil is improved with geopolymers in stages and without disrupting port operation.

Lifting and stabilisation of concrete slabs

URETEK geopolymer resins are suitable for levelling and strengthening of parking lots and manoeuvring areas for heavy duty vehicles, loaders and gantry cranes. Furthermore, geopolymers can be used to repair concrete floors and covers of port warehouses and docks, the condition of which has deteriorated due to exposure to water.

Concrete slabs are levelled by using Slab Lifting method. For more efficient stabilisation of port structures, Deep Injection method is used. It enables strengthening of soil under the structure. Geopolymers force out excess water, thus increasing the load-bearing capacity of soil.

Advantages of URETEK methods

Formerly, repair of concrete surfaces meant removal of all cover slabs, compacting of filling material and reinstallation of concrete slabs. In that case, major repairs are similar to new port construction, involving not only high cost, but also long-term stoppage of port operations, causing additional costs and loss.

URETEK technology makes it possible to perform work without dismantling concrete slabs and interrupting port operations. Materials and equipment required for geopolymer injection fit in a single truck. For injecting geopolymers under concrete slabs and deep in soil, holes with diameter of 12–16 mm are drilled. These holes are simply closed later. Stabilised and repaired sections can be used 15 minutes after completion of works.


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Elimination of floor subsidence in stores and warehouses without changing their opening hours

Concrete floors of large warehouses, supermarkets and logistics centres may also suffer from subsidence or tilting

Modern URETEK geopolymers injection method allows lifting concrete floor slabs and stabilise them without vacating the premises and disrupting daily work.

Floor slabs in large warehouse and commercial areas are designed in view of daily impact of stationary structures. Concrete floor must also handle loads caused by loading machinery and other warehouse equipment. In case of exceeding permitted maximum static or dynamic loads or in case of changes in soil properties under the structure (weakening of soil due to changes in surface water level, breakage of water or sewerage pipes), it is likely that floor slabs sink or tilt.

The damage described above can cause minor discomfort resulting from changed position of commercial and warehouse equipment, but it can also lead to accidents and situations that endanger human health and life.

Complexity of lifting and stabilising concrete slabs

Unfortunately, subsidence of concrete floor in a warehouse or commercial premises is not always noticed in time. Considering that restoration of concrete floor and strengthening of the soil under the floor requires dismantling of concrete slabs when using traditional methods, the repairs are often postponed as they cause major loss to the owners of premises resulting from long-term work stoppage.

Instead of applying systemic measures, owners often seek temporary solution by using all kinds of supports and bases. However, such an approach to the problem may obviously lead to unpleasant consequences.

Lifting and stabilisation of floor by using geopolymers

Sunken sections of concrete floor can be lifted and the soil under the structure can be strengthened by using URETEK geopolymers injection method.

In that case, there is no need for dismantling concrete slabs, involving heavy machinery or performing earthworks. In order to stop subsidence of concrete slabs and levelling them, geopolymer material has to be inserted deep under the floor in the soil under the structure (Deep Injection method) or in the space between soil and concrete slab (Slab Lifting method).

Immediately after injection, geopolymer resins expand and take up all vacant space in the soil under the structure, compact the soil and harden within only 15 minutes. URETEK geopolymers injection technology allows increasing compressive strength of soil up to 10.6 МPа.

Injection can be done without dismantling sunken slabs. It requires drilling just a few technical holes with diameter of 16mm in the concrete for pipes intended for inserting geopolymer material. Meanwhile, URETEK equipment can be located up to 120 m from the actual place of injection.

Geopolymer material is inserted in soil through special hoses that can easily be moved in the room between shelving and other equipment. Thus, it is not necessary to vacate premises from goods and equipment. Furthermore, the hardening speed of URETEK geopolymer resins allows lifting and stabilisation of concrete slabs at night. But warehouse or store does not have to stop work even if the floor needs to be lifted during working hours. Due to mobility and compact dimensions of the equipment, there is only minimum disturbance in daily operation.

Advantages of URETEK technology

The process of lifting and levelling sunken concrete slabs is monitored in real time. This is done by using special laser levels with measurement accuracy of ± 1 mm. Ground floor slabs can be lifted by maximum 20 cm. After restoration of former floor height, cracks can be eliminated in partition walls supported by sunken slabs. Restoring floors by means of URETEK method allows saving up to 25% compared to traditional methods.


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