Successful sprayed concrete requires the combination of many aspects of modern concrete technology especially concrete admixture chemistry, together with modern materials handling technology.
The increasing demands for cost-effectiveness and the protection of health and the environment mean that sprayed concrete has been in continuous development. Sika’s products for sprayed concrete represent the newest generation and cutting-edge technologies that have resulted from more than one hundred years of involvement in the business. With this experience, expert knowledge and a focus on performance and economy, Sika provides reliable proven solutions!
The multiple demands placed on sprayed concrete today no longer allow standard solutions. Dependent on the spray process and the type of structure, different conditions are imposed on the sprayed concrete during application and in service. In tunnel construction sprayed concrete is normally used for excavation stabilization, in open-pit mining and on major construction sites it is typically used for rock and soil stabilization on slopes.
In bridge and other civil engineering repair and refurbishment works, sprayed concrete is often used specifically because formwork can thereby be dispensed with. Through more than 100 years of activity in these complex areas, Sika profoundly understands the difficulties and challenges and provides solutions that surmount them.
- Sigunit® -Shotcrete accelerators, available as liquid, powder or instant powder, for the highest strength development, ideal for overhead applications and building-up thicker layers.
- Sika ViscoFlow® – High range water reducing superplasticizers for better workability of the concrete mix, higher compressive strength and increased durability of the shotcrete.
- SikaTard® – Cement hydration stabilizer to ensure long term stabilization of the concrete mix, enabling optimum shotcrete application with the highest flexibility – Always just in time.
- SikaPump®- Pumping aids improve the pumpability of the concrete mix. For a smooth pumping process over long distances and time, with minimal friction and wear on the equipment.
- SikaTell® – Colloidal silica additive for stabilizing the concrete mix cohesion and thereby reducing rebound and improving the long-term durability of the shotcrete.
- SikaFibre® – Steel or synthetic fibers used to increase the resilience and energy absorption of the shotcrete. Highest performance with maximum efficiency.
- SikaFume® – Micro silica additives that significantly improves the shotcrete and its durability: Optimum adhesion and minimal rebound, followed by watertight durability.
- FlexoDrain – Substrate drainage system installed to allow the shotcrete application in case of moderate water ingress and protecting the lining from aggressive mountain water.
- Aliva®- Specialist equipment for all types of wet and dry process shotcrete application and accelerator dosing. Off the-shelf and tailor-madesolutions.
- SikaCare- Reduces the adhesion of cement mortar and concrete to the equipment, allowing extended use, lower wear and easier cleaning after the application.
- SikaPump®-Start 1- Lubricant for concrete pumps, significantly reducing the friction between concrete and hoses/pipes, during the start-up of the pumping process.
- SikaShot® – Highly accelerated spray mortar for consolidating and pre-sealing the substrate. Ideal pretreatment under difficult conditions for the optimum shotcrete lining.
Sika Shotcrete worldwide
Gotthard Base Tunnel, Railway, Switzerland
As of 2017, the new flat trajectory railway through the Swiss Alps will link Europe’s high-speed railway networks. The core of the new link is the Gotthard Base Tunnel with a length of 57 km. Sika was and is a significant participant in the excavation stabilization for the expansion of this project that has already been described as the ‘structure of the century’.
East Side Access, New York City Subway, USA
This is one of the largest infrastructure projects in the USA, designed to bring the Long Island Rail Road into a new East Side station to be built below, and incorporated into, Grand Central Terminal. Shotcrete is used to line areas that have unusual shape, where standard cast-in-place lining cannot be used, including stations, cross-overs and arches.
Potrerillos Dam, Hydropower, Argentina
The project consists of an earth dam supporting a 1.300 hectare reservoir. This is 116 meters high, with a central impermeable core tunnel of different diameters, shape and section lengths within its overall 15 km. These were all lined with entirely Shotcrete using Sigunit accelerators through a robot arm.
Pongkor Mine, Indonesia
The Pongkor Gold Mine is operated by ANTAM and is located in West Java, Indonesia. Gold ore is sourced from 3 different veins through conventional and mechanized cut and fill mining. Sika Indonesia is a longstanding partner of the Pongkor mining team and supplies a range of products to the project, which include shotcrete admixtures and fibers for an efficient construction, strengthening and stabilization of the important mine’s underground infrastructure.