technologies

High material properties, strength grade of 120 according to Technical Conditions document 267 of Ministry of Transport’s Road and Motorway Directorate

Virtually unlimited lifetime granted by high density of the UHPC Valucem and its resistance to environmental effects

Possibility to design spatial thin-walled elements with sufficient load bearing capacity achieved in many cases without soft reinforcement

Fine-grained structure and very high fluidity allow for perfect moulds, reliefs and plastic patterns

The low weight and subtlety of of Valucem elements reduces the requirements for transport and production technology

With appropriate admixtures, Valucem can be utilized for 3D-printing

The listed properties create conditions for use in production of constructions where Valucem can be more advantageous than ordinary concrete.

Valucem
Valucem web světlý

Bridges of small to medium span, bridge segments, prestressed bridge girders, reinforcement of horizontal and vertical load-bearing frames, facade features, facing slabs, monolithic thin-wall constructions, street furniture (such as benches and rubbish bins), architectural and design work (statues, sculptures).

Štvanická lávka HolKa

Multicomponent fine-grain cement-based composite produced from prime fractions of silica filling of maximum grain size of 2mm, latent-hydraulic fillers and modifying additives. The mixture contains a liquid superplasticizer and a selected type and dose of fibres (steel, polymer). The mixture contains a liquid superplasticizer and a selected type and dose of fibres (steel, polymer). The composition ensures high compressive and tensile strength in bending, high adhesion to the substrate and easy filling of even very complex mould shapes. The colouring can be altered with pigments.

Valucem web světlý – projekty

UHPC Valucemcan be used for the production of thin (shell) prefabricated structures as well as precise and complex parts, e.g. facade elements, street furniture, replacements and replicas of stucco and stone products.


Note:
a) The properties characterize the basic range of Valucem UHPC. These properties can be altered, according to the purpose of projects and requirements of construction elements, in cooperation with the UHPC manufacturer.
b) The parameter significantly depends on the type and dosage of steel microfibres and can be altered according to the needs of the design and requirements of the construction elements
Characteristics at 28 days a) Symbol Unit Norm Valucem 120
Strength grade fck MPa EB 1992 - 1 - 1 C 120
Recommended dosage of steel microfibres Bulk weight Vf Bulk percentage TP 267 MD ČR 1,5
Bulk weight ρ kg/m³ EN 12390 - 7 2400 ± 2 %
Characteristic cylindrical strength MPa EB 1992 - 1 - 1 120
Average cylindrical compressive strength on a 100/200 mm cylinder fcm MPa EN 12390 - 3 >130
Characteristic residual flexural tensile strength b) fctk,f MPaMPa TP 267 MD ČR >12
Average residual flexural tensile strength b) fR1m MPa EN 14651 >17
Residual strength class from crack opening displacement at 3,5 mm/0,5mm ratio b) fR3m/fR1m MPa EN 14651, TP 267 MD ČR >0,7
Resistance to deicing agents Maximum waste cycles2 Czech technical standard 731326, method C >200
Elastic modulus E GPa ISO 1920 - 10 >46

The use of high-value concrete in the reinforcement of horizontal bridge structures

The project for the verification of UHPC laying was aimed at improving the physical and technical parameters of existing horizontal elements of bridge structures (bridge decks, crossbeams, etc.) and slab structures placed on the ground (roadways, parking lots, floors, etc.).

By installing a structural layer of UHPC, it is possible to increase the payload and create an alternative durable horizontal layer with insulation capacity, especially for older bridges. This can also be applied on newly built bridge structures.v

There is often no choice but to remove the existing structure and replace it with a new, more load-bearing one.

The newly installed layer of high-performance concrete is capable of combining several functions, which is the high added value of this technology. It combines both the function of reinforcing the structure, the damp-proofing layer function and the ability to create a highly resistant and durable final walkable or driving layer. Due to its unique mechanical and physical properties, UHPC Valucem can be applied in smaller thicknesses. In addition to lower structural loads, this means a lower volume of material used and therefore lower consumption of primary raw materials and therefore lower transport and heavy machinery costs. All of this ultimately translates into a lower environmental burden.

In the development of this technology for reinforcing horizontal surfaces or surfaces with a slight gradient, a modification of the fresh UHPC Valucem mix was developed to allow paving even in a slight gradient. At the same time, the final surface treatment procedures were verified to ensure sufficient anti-slip properties of the final surface.In the development of this technology for reinforcing horizontal surfaces or surfaces with a slight gradient, a modification of the fresh UHPC Valucem mix was developed to allow paving even in a slight gradient. At the same time, the final surface treatment procedures were verified to ensure sufficient anti-slip properties of the final surface.

Valucem web světlý – projekty

Technical and application conditions

The use of UHPC in the reinforcement of horizontal surfaces of bridge structures requires that the newly formed UHPC reinforcement layer is applied to the existing exposed concrete /binding / layer for good anchorage of the reprofiling layers. The exposed subgrade has to be sufficiently load-bearing and “open”. After cleaning, there are visible fine and coarse aggregate grains on the surface, including larger air pores in the mortar portion.

A fundamental characteristic of fresh UHPC mix is its large spillage; the mix is essentially self-levelling. By applying suitable admixtures to the fresh mix, the cohesion of the mix should be increased so that the UHPC layer can be discharged. Modified Valucem UHPC allows the formation of slump layers to at least 6 % gradient.

Within practical tests and implementations dealing with reinforcement and final surface treatment, the following has been successfully carried out:

  1. reinforcement of a brick columns in the premises of PREMIX servis, Libiš
  2. repair of footbridge in- Chemopetrol industrial estate
  3. repair of a parking area – company PREMIX servis, Libiš
  4. repair of an influx tank in Chemopetrol industrial estate
  5. reinforcement of the crown of an aeration tank of a sewage water disposal plant in Chemopetrol industrial estate
Valucem web světlý – projekty
EN