WO2019012436A1 - Système d'éléments en béton surélevé semi-préfabriqué - Google Patents

Système d'éléments en béton surélevé semi-préfabriqué Download PDF

Info

Publication number
WO2019012436A1
WO2019012436A1 PCT/IB2018/055096 IB2018055096W WO2019012436A1 WO 2019012436 A1 WO2019012436 A1 WO 2019012436A1 IB 2018055096 W IB2018055096 W IB 2018055096W WO 2019012436 A1 WO2019012436 A1 WO 2019012436A1
Authority
WO
WIPO (PCT)
Prior art keywords
concrete
precast
upper layer
cement
per cubic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IB2018/055096
Other languages
English (en)
Inventor
Rolands CEPURITIS
Bradley Justin PEASE
Janis Oslejs
Janis KAMARS
Jörg-Dietrich Albrecht Franz FREIHERR VON UND ZU WEILER
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Filigran Primekss Sia
Original Assignee
Filigran Primekss Sia
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Filigran Primekss Sia filed Critical Filigran Primekss Sia
Priority to SE1930405A priority Critical patent/SE543320C2/en
Publication of WO2019012436A1 publication Critical patent/WO2019012436A1/fr
Anticipated expiration legal-status Critical
Priority to NO20200060A priority patent/NO348116B1/en
Ceased legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B5/00—Floors; Floor construction with regard to insulation; Connections specially adapted therefor
    • E04B5/16—Load-carrying floor structures wholly or partly cast or similarly formed in situ
    • E04B5/32—Floor structures wholly cast in situ with or without form units or reinforcements
    • E04B5/36—Floor structures wholly cast in situ with or without form units or reinforcements with form units as part of the floor
    • E04B5/38—Floor structures wholly cast in situ with or without form units or reinforcements with form units as part of the floor with slab-shaped form units acting simultaneously as reinforcement; Form slabs with reinforcements extending laterally outside the element
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • C04B28/04—Portland cements
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/02—Portland cement
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/01—Reinforcing elements of metal, e.g. with non-structural coatings
    • E04C5/06—Reinforcing elements of metal, e.g. with non-structural coatings of high bending resistance, i.e. of essentially three-dimensional [3D] extent, e.g. lattice girders
    • E04C5/065—Light-weight girders, e.g. with precast parts
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/01—Reinforcing elements of metal, e.g. with non-structural coatings
    • E04C5/06—Reinforcing elements of metal, e.g. with non-structural coatings of high bending resistance, i.e. of essentially three-dimensional [3D] extent, e.g. lattice girders
    • E04C5/065—Light-weight girders, e.g. with precast parts
    • E04C5/0653—Light-weight girders, e.g. with precast parts with precast parts
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/07—Reinforcing elements of material other than metal, e.g. of glass, of plastics, or not exclusively made of metal
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/07—Reinforcing elements of material other than metal, e.g. of glass, of plastics, or not exclusively made of metal
    • E04C5/073—Discrete reinforcing elements, e.g. fibres
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00612—Uses not provided for elsewhere in C04B2111/00 as one or more layers of a layered structure
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/52—Constituents or additives characterised by their shapes
    • C04B2235/5208—Fibers
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/50—Constituents or additives of the starting mixture chosen for their shape or used because of their shape or their physical appearance
    • C04B2235/54—Particle size related information
    • C04B2235/5463—Particle size distributions
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/02—Portland cement
    • C04B7/06—Portland cement using alkaline raw materials
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/14—Cements containing slag
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/14—Cements containing slag
    • C04B7/147—Metallurgical slag
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies
    • Y02W30/91—Use of waste materials as fillers for mortars or concrete

Definitions

  • the present invention relates to a semi-precast elevated concrete element system.
  • Typical semi-precast elevated concrete elements consist of prefabricated reinforced concrete elements with an upper layer of reinforced concrete, which is either bonded or unbonded to the prefabricated reinforced concrete elements.
  • Fig. 1A illustrates a bonded version of a prior art elevated concrete element - a slab.
  • This known type of semi-precast elevated concrete element is implemented as follows:
  • the prefabricated reinforced concrete elements are produced in a factory and transported to a building site;
  • the prefabricated reinforced concrete elements are erected on temporary supports, typically aided by a crane;
  • additional reinforcement e.g., negative moment reinforcement, two-way reinforcement, punching shear reinforcement, etc.
  • additional reinforcement e.g., negative moment reinforcement, two-way reinforcement, punching shear reinforcement, etc.
  • the shrinkage of the in-situ cast upper layer of concrete is additionally restrained internally by the reinforcement.
  • the restraint of the shrinkage of the upper concrete layer results in the development of tensile stresses and cracking in said upper layer, as illustrated in Fig. 1A.
  • Cracking of the upper layer of concrete may have durability and serviceability implications. When the element is exposed to loads, cracks in the compression zone of the element first need to close before compressive stresses are transferred. Some amount of element deflection is required to close these cracks which leads to an overall increased deflection for this type of semi-precast elevated concrete element.
  • the invention provides an integrated semi-precast elevated concrete element system comprising a precast concrete panel with partially embedded reinforcing elements for shear transfer and reinforcement for additional load capacity, and an in-situ cast upper layer of a modified concrete having positive length change, i.e.
  • the in-situ cast upper layer of concrete comprises: hydraulic cement being a Portland cement or blended cement: 200 to 700 kg/m 3 of concrete, more preferred 225 to 600 kg/m 3 of concrete and even more preferred 250 to 500 kg/m 3 of concrete; water, at a ratio of water: hydraulic cement of 0.30 to 0.75 by weight, preferably from 0.30 to 0.65 by weight; aggregate, with a maximum size of 40 mm, preferably with maximum size of 30 mm and aggregate: concrete ratio from 0.45 to 0.85 by volume; fiber reinforcement, 10 to 200 kilograms of steel fiber per cubic meter of concrete, more preferred 15 to 150 kilograms of steel fiber (e.g.
  • the chemical prestressing additive is a mineral admixture adapted to create hydration products, which are volumetrically larger than the volume of the reactants, where the length change at an infinite time and drying conditions of 50% RH and 20°C is estimated by plotting the length change data collected in accordance with ASTM C 157 (Standard Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete; Book of Standards Volume: 04.02, ASTM International) as a function of the inverse square root of time and extrapolating the infinite shrinkage after 28-days of drying.
  • ASTM C 157 Standard Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete; Book of Standards Volume: 04.02, ASTM International
  • Some known chemical prestressing additive include magnesium oxide, calcium aluminate, tricalcium aluminate or combinations of these or other substances causing chemical prestressing of restrained concrete elements.
  • the precast concrete panel preferably comprises Portland cement concrete optionally with pozzolan(s) and/or chemical admixture(s) mixed therein.
  • the precast concrete panel is optionally prestressed.
  • the precast concrete panel may comprise a hollow core, or flat panel, or double-T, or U-shaped, or I-shaped precast concrete profile.
  • the partially embedded reinforcing elements of the precast concrete panel are preferably geometrically asymmetric with an increased area of reinforcement in the part of the reinforcing element embedded in the precast concrete panel. Said reinforcing elements may be lattice girders or reinforcing profiles made of metal or fibre-reinforced plastic.
  • the in-situ cast upper layer may further contain metallic or non-metallic bars or other reinforcing elements.
  • Fig. 1 is a schematic view of the impact of varying length change behaviors of the upper in-situ concrete layer on the induced deformations of a bonded semi-precast elevated concrete element (impact of self-weight on deflection is not shown), where Fig. 1A illustrates shrinkage of the prior art in-situ concrete layer (deflection); Fig. IB shows no shrinkage of in-situ concrete layer; and Fig. 1C illustrates overcompensation of shrinkage of in-situ concrete layer (negative deflection) according to the present invention;
  • Fig. 2 A shows a frontal and Fig, 2B - side views of an example of a steel lattice girder, which can be used in the precast element;
  • FIG. 3 pictures showing load-induced flexural deflection testing of semi-precast elevated concrete element system panels; where application of uniform load was realized using water-filled palette tanks and deflection instrumentation was implemented by dial gauges;
  • Fig. 4 - chart showing reduction in flexural load-induced deflections for 5 m span of the invented semi-precast elevated concrete element system (P3 line) compared to traditional reinforced concrete systems of the same thickness with (N2 line) and without (Nl line) negative moment reinforcement.
  • Fig. 5 - chart showing reduction in flexural load-induced deflections for 7.5 m span of the invented semi-precast elevated concrete element system (P8 line) compared to traditional reinforced concrete systems of the same thickness with (N7 line) and without (N6 line) negative moment reinforcement.
  • Figure 1 shows a schematic view of the semi-precast elevated concrete composite elements, consisting of a precast concrete panel and an in-situ cast upper layer of a concrete.
  • the precast concrete panel has reinforcing elements, like that shown in Figure 2, partially embedded in its top surface for the purpose of transfer of shear between the precast concrete panel and the in-situ cast upper layer of concrete, and longitudinal reinforcement for improved load capacity.
  • a steel lattice girder (Fig. 2) is partially embedded into the precast concrete with the lower chord contained in the precast element and the upper chord and diagonals protruding from the precast element.
  • the first aspect of the invention relates to the combination of these components (i.e., precast concrete panel and an in-situ cast upper layer of a concrete) wherein the in-situ cast upper layer of concrete includes fiber reinforcement and chemical prestressing additive.
  • Experimental results demonstrate the invention provides surprising and unexpected improvements in the flexural rigidity compared to previously known semi-precast elevated concrete composite elements.
  • Figures IB and 1C illustrate the theoretical deflected shape induced by the length change of the in-situ cast upper layer of concrete in an integrated (i.e., bonded) semi-precast elevated concrete composite element wherein the upper layer of concrete has no shrinkage and an overcompensated shrinkage (i.e., net expansion), respectively.
  • precast concrete element comprising:
  • a concrete mix consisting of components including hydraulic cement, water, aggregate, mineral admixtures (optional), chemical admixtures (optional), and fiber reinforcement (optional) and
  • Table 2 provides parameters of comparison tests of the invented thin semi- precast elevated concrete element system and prior art reinforcement bar reinforced concrete system of the same thickness with and without negative moment (i.e., upper) reinforcement.
  • the prefabricated reinforced concrete elements consisted of a 5 cm thick concrete thickness with partially embedded lattice girders as described in Table 2.
  • the prefabricated reinforced concrete elements were supported on the ends, to the described span lengths, and with additional evenly spaced temporary supports to allow placement of the upper layer of concrete.
  • the upper layer of concrete was placed over the prefabricated reinforced concrete elements and cured in accordance with common concreting practice. After curing, the temporary supports were removed and a uniform loading was simulated as shown in Figure 3 by means of water-filled palette tanks to a level of 5.9 kN/m (600 kg/m). Table 2 introduces sample identifications for the resulting 6 systems tested.
  • Figures 4 and 5 present the experimental evidence of this significant increase in the effective bending stiffness of the integrated semi-precast elevated concrete composite element across two span lengths, 5 and 7.5 m, respectively (cf. also Table 2).
  • Figure 4 presents results from the 5 m span samples Nl, N2 and P3. Comparing the load-deflection response for samples Nl and N2 illustrates the impact cracking, introduced by the internal restraint from the upper reinforcement detail in the N2 sample, has on flexural rigidity. The instantaneous deflection is increased by approximately 3.5 mm from Nl to N2. While the deflection is better controlled by Nl, it is noted that there is a lack of negative moment reinforcement in Nl, resulting in a system that is less robust overall. The P3 sample realizes a still further increased flexural ridigity than the Nl sample, with 2.1 mm less instantaneous load-induced deflection, while still providing significant reinforcement through the incorporation of steel fiber into the mix.
  • Figure 5 presents results for 7.5 m span samples N6, N7 and P8. Similar as for the 5 m span samples, the P8 sample offers the highest level of flexural rigidity with an instantaneous deflection of 7.7 mm, followed by the samples without (N6, 17.9 mm of instantaneous deflection) and with (N7, 20.5 mm of instantaneous deflection) negative moment reinforcement. Again, the increased level of resistance to load-induced deflections for the P8 sample was not expected as structural analysis of sample N6 and P8 (wherein the in-situ cast upper layer is treated as unreinforced concrete) would estimate an identical immediate deflection.
  • the amounts of the individual components in the concrete for the in-situ cast upper layer and the precast concrete element may vary widely.
  • Ranges of the content of hydraulic cement, a product complying with standard specifications including e.g., EN 197, ASTM C 150, ASTM C 595, etc., to yield the embodiments of the presented invention include 200 to 700 kg/m 3 , more preferred 225 to 600 kg/m 3 and even more preferred 250 to 500 kg/m 3 .
  • Hydraulic cement may consist of Portland cement or blended cements consisting of Portland cement interground or mixed with mineral admixtures.
  • Mineral admixtures which are known to one skilled in the art, may include ground- granulated blast furnace slag, fly ash, silica fume, limestone powder, burnt shale and may comprise between 5-95% by mass of cement in blended cement.
  • the ratio of watenhydraulic cement is from 0.30 to 0.75 by weight, preferably from 0.30 to 0.65 by weight.
  • the ratio of aggregate: concrete is preferably from 0.45 to 0.85 by volume.
  • Aggregate which is a term familiar to one skilled in the art, comprise fine and coarse aggregates up to a maximum aggregate size of 40 mm, preferably up to 35 mm and more preferably maximum aggregate size of 30 mm.
  • Chemical admixtures are a series of products known by one skilled in the art complying to standard specifications including e.g., EN 934 series, ASTM C 260, ASTM C 494, ASTM C 1017, ASTM C 1582. Chemical admixtures may be included, as necessary, to achieve other desired performances in fresh concrete, e.g., enhanced workability, accelerated or retarded setting, and hardened concrete, e.g., resistance to damage from freeze-thaw cycling, enhanced strength properties.
  • fibers for fiber reinforced concrete are created from numerous materials by various methods and to various shape, lengths and aspect ratios (i.e., ratio of length:diameter or length:equivalent diameter).
  • Appropriate materials for fibers to realize the beneficial embodiments of the presented invention including various steel types, including stainless, carbon steel and galvanized; mineral and polymer materials, including acrylic, aramid, basalt, carbon, nylon, polyester, polyethylene, and polypropylene; processed and unprocessed natural fibers, including coconut, bamboo, jute, flax and wood fiber.
  • Preferred materials for fibers are steel, mineral fibers, polymer fibers, or combinations thereof. Particularly preferred are cold-drawn carbon steel fiber with hooked-ends or undulations, monofilament synthetic mineral or synthetic polymer fibers, or combinations thereof.
  • Ranges of the content of fibers to yield the beneficial embodiments of the presented invention vary widely and depend on the material type.
  • Preferred contents of steel fiber reinforcement are 10-200 kilograms of steel fiber per cubic meter of concrete, more preferred is 15-150 kilograms of steel fiber per cubic meter of concrete.
  • the contents of synthetic polymer fiber are 0.2-30 kilogram of synthetic polymer fiber per cubic meter of concrete.
  • Preferred contents of synthetic mineral fiber are 1-100 kilogram of synthetic mineral fiber per cubic meter of concrete.
  • Additives for chemical prestressing which is a concept known to one skilled in the art, are added to the concrete mix for the in-situ cast upper layer.
  • Figure 6 shows experimental length change results from various concretes with different contents of chemical prestressing additives and fibers.
  • Table 1 provides the concrete compositions used for results presented in Figure 6. The results are plotted versus the inverse square root of the specimen age which allows for the estimation of the net length change at an infinite time by means of linear extrapolation as shown by the broken lines in the figure.
  • a beneficial embodiment of the presented invention based on flexural load-induced deflection experiments described below, is an unexpected level of beneficial negative deflection of the integrated semi-precast elevated concrete composite element prevails when the concrete for the upper layer has an estimated net expansion of at least 75 ⁇ at an infinite time.
  • Ranges of chemical prestressing additives will vary widely to achieve the performance described in Figure 6, with preferred contents between 0.5-50% by mass of hydraulic cement and more preferred 1- 30% by mass of hydraulic cement.
  • the observed improved flexural deflection resistance offered by the said integrated semi-precast elevated concrete composite element provides a beneficial structural performance and larger span length than previously feasible can be achieved.
  • a second aspect of the invention therefore relates to the design process for the integrated semi-precast elevated concrete composite element, wherein the improved flexural resistance is considered.
  • Limits on the flexural deformation of concrete elements is known in the design process for structural reinforced concrete. In certain cases and for particular elements, flexural deformation limits may control geometric parameters; mainly span length and also element thickness, or both; of the element.
  • the structural design and architectural considerations of a structure are improved as the allowable span length of the said integrated semi-precast elevated concrete element can be increased while maintaining the deflection control, load capacity, and total thickness compared to use of ordinary concrete for the in-situ cast upper layer.
  • the allowable load level of the said integrated semi-precast elevated concrete element is increased while maintaining the deflection control, span length, and total thickness compared to use of ordinary concrete for the in-situ cast upper layer.
  • design options including combinations of the above embodiments; being increased span length and increased capacity are also possible.
  • a design option of an increased load capacity and increase allowable span length, while maintaining sufficient deflection control, is possible.
  • the precast concrete element comprises a 50 mm thick flat plate of a C25/30 concrete with a minimum age of 28 maturity days and two individual evenly spaced partially embedded steel element in the concrete.
  • the steel element consists of the triangular shaped girder, as in Figure 2, with a upper chord diameter of 10 mm, a diagonal diameter of 6 mm, a lower chord diameter of 6 mm, a girder width of 80 mm and a girder height of 160 mm.
  • Said in-situ cast upper layer of concrete comprises a 220 mm thickness of a steel fiber reinforced concrete with 45 kilograms of steel fibers per cubic meter of concrete, 20 kilograms of a chemical prestressing additive (MgO) per cubic meter of concrete and 300 kilograms of CEM I 42.5N cement per cubic meter of concrete.
  • the final integrated semi-precast elevated concrete composite elements are used as a multiple continuous span elevated element with a span length of 7.5 meters subject to 5 kilonewtons per square meter uniform loading.
  • the increased effective bending stiffness provided by the invention yields a span-to-deflection ratio under the said load condition of approximately 940.
  • the allowable span length is 6 meters.
  • the in-situ cast concrete shall have a thickness of 270 mm and consequently the total thickness shall be 320 mm.
  • the increased rigidity of the invented system means that a 20 mm increase in the total thickness is sufficient to accommodate a 1.5 meter increase in the allowable span length compared to the design based on current building design codes.
  • the same 1.5 meter increase in the allowable span length using the design approach in current building design codes requires a 70 mm increase in the total thickness.
  • the precast concrete element comprises a 50 mm thick flat plate of a C25/30 concrete with a minimum age of 28 maturity days and two individual evenly spaced partially embedded steel elements in the concrete.
  • the steel elements consist of the triangular shaped girders, as in Figure 2, with a upper chord diameter of 10 mm, a diagonal diameter of 6 mm, a lower chord diameter of 6 mm, a girder width of 80 mm and a girder height of 130 mm.
  • the said in-situ cast upper layer of concrete comprises a 160 mm thickness of a steel fiber reinforced concrete with 10 kilograms of synthetic fibers per cubic meter of concrete, 35 kilograms of a chemical prestressing additive (tricalcium aluminate) per cubic meter of concrete and 325 kilograms of CEM II/A-V 52.5R cement per cubic meter of concrete.
  • the final integrated semi-precast elevated concrete composite elements have a total thickness of 210 mm and used as a multiple continuous span elevated element with a span length of 6 meters.
  • the increased effective bending stiffness provided by the invention allows a uniform loading of 5 kilonewtons per square meter.
  • design approaches using ordinary concrete for the in-situ cast upper layer allows a uniform loading of 3 kilonewtons per square meter for the same total thickness of 210 mm and span length of 6 meters.
  • the invention allows for an increase of 2 kilonewtons per square meter in the allowable load level while maintaining the span length, deflection control, and total element thickness compared to the design approach using ordinary concrete for the in-situ cast upper layer.
  • a third aspect of the invention is the method to produce the concrete for the in-situ cast upper layer with fiber reinforcement and chemical prestressing additives.
  • said method comprises the steps of: (i) providing an initial concrete mixture including hydraulic cement, aggregate, water, and optional chemical admixtures by a ready-mix concrete facility and transporting said mixture to the jobsite (e.g. in a rotating drum ready-mix truck); (ii) incorporating fiber reinforcement and chemical prestressing additives into the initial concrete mixture on site using purpose-built equipment, and (iii) the concrete placing, consolidating (compacting), leveling, finishing and curing.
  • said method comprises the steps of: (i) providing a concrete mixture including hydraulic cement, aggregate, water, optional chemical admixtures, and fiber reinforcement by a ready-mix concrete facility and transporting said mixture to the jobsite, (ii) incorporating chemical prestressing additives into said concrete mixture on site, and (iii) the concrete placing, consolidating (compacting), leveling, finishing and curing.
  • said method comprises the steps of: (i) providing a concrete mixture including hydraulic cement, aggregate, water, optional chemical admixtures, fiber reinforcement, and chemical prestressing additive by a ready-mix concrete facility and transporting said concrete mixture to the jobsite, and (ii) the concrete placing, consolidating (compacting), leveling, finishing and curing.

Landscapes

  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Structural Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Civil Engineering (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Rod-Shaped Construction Members (AREA)
  • Bridges Or Land Bridges (AREA)
  • Machines For Laying And Maintaining Railways (AREA)
  • Reinforcement Elements For Buildings (AREA)
  • Manufacturing Of Tubular Articles Or Embedded Moulded Articles (AREA)

Abstract

La présente invention concerne un système d'éléments en béton surélevé semi-préfabriqué, comprenant les composants suivants : (i) un panneau en béton préfabriqué avec des éléments de renforcement partiellement incorporés pour le transfert de cisaillement et le renforcement pour une capacité de charge supplémentaire, et (ii) une couche supérieure coulée in situ d'un béton ayant une dilatation nette estimée d'au moins 75 με à un temps infini ; la couche supérieure coulée in situ de béton comprenant : du ciment hydraulique étant un ciment portland ou un ciment mélangé : 200 à 700 kg/m3 de béton, de préférence de 225 à 600 kg/m3 de béton avec une préférence pour 250 à 500 kg/m3 de béton ; de l'eau, à un rapport de ciment hydraulique de 0,30 à 0,75 en poids, de préférence de 0,30 à 0,65 en poids ; un agrégat ayant une taille maximale de 40 mm, de préférence avec une taille maximale de 30 mm et agrégat : rapport de béton de 0,45 à 0,85 en volume; renfort de fibres, de 10 à 200 kilogrammes de fibre d'acier par mètre cube de béton, de préférence de 15 à 150 kilogrammes de fibre d'acier par mètre cube de béton ; et/ou de 0,2 à 30 kilogrammes de fibre de polymère synthétique par mètre cube de béton ; et/ou 1 à 100 kilogramme de fibre minérale synthétique par mètre cube de béton ; additif de précontrainte chimique : 1 à 30 % en masse de ciment hydraulique et suffisamment pour atteindre la cible de changement de longueur nette positive ci-dessus ; l'additif de précontrainte chimique étant un mélange minéral adapté pour créer des produits d'hydratation, qui sont volumétriquement plus grands que le volume des réactifs lorsqu'ils sont ajoutés à du béton plastique ; et avec un changement de longueur à un temps infini et des conditions de séchage de 50 % d'humidité relative et de 20 °C étant estimé en traçant les données de changement de longueur collectées conformément à la norme ASTM C 157 en tant que fonction de la racine carrée inverse du temps et par extrapolation du retrait infini après 28 jours de séchage.
PCT/IB2018/055096 2017-07-14 2018-07-11 Système d'éléments en béton surélevé semi-préfabriqué Ceased WO2019012436A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
SE1930405A SE543320C2 (en) 2017-07-14 2018-07-11 Semi-precast elevated concrete element system
NO20200060A NO348116B1 (en) 2017-07-14 2020-01-17 Semi-precast elevated concrete element system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
LVP-17-49A LV15383B (lv) 2017-07-14 2017-07-14 Daļēji saliekama dzelzsbetona pārseguma elementu sistēma
LVP-17-49 2017-07-14

Publications (1)

Publication Number Publication Date
WO2019012436A1 true WO2019012436A1 (fr) 2019-01-17

Family

ID=59702783

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2018/055096 Ceased WO2019012436A1 (fr) 2017-07-14 2018-07-11 Système d'éléments en béton surélevé semi-préfabriqué

Country Status (4)

Country Link
LV (1) LV15383B (fr)
NO (1) NO348116B1 (fr)
SE (1) SE543320C2 (fr)
WO (1) WO2019012436A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110183128A (zh) * 2019-06-05 2019-08-30 滁州市炬基节能新型建材有限公司 一种建筑垃圾再生高活性矿物掺合料及其制备
CN110526646A (zh) * 2019-08-29 2019-12-03 徐州金盟新型建材有限公司 一种具有隔热功能的建筑构件
CN113185881A (zh) * 2021-05-10 2021-07-30 北京固斯特国际化工有限公司 一种针对混凝土烟囱的渗透反应型防腐材料及其应用
CN114577563A (zh) * 2022-02-11 2022-06-03 中国电建集团西北勘测设计研究院有限公司 一种自愈合混凝土裂缝修复检验方法
EP4005761A4 (fr) * 2019-07-22 2023-08-16 HPC Okinawa Co., Ltd. Béton précontraint

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3885369A (en) * 1973-03-08 1975-05-27 Vigarex Ets Structural element
JPH02311639A (ja) * 1989-05-26 1990-12-27 Takenaka Komuten Co Ltd 合成床の構築方法
US5448866A (en) 1989-09-07 1995-09-12 Kajima Corporation Trusses and precast concrete slabs reinforced thereby
WO2011053103A2 (fr) * 2009-10-26 2011-05-05 Primeteh, A/S Béton composite pour dalles de sol et radiers

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3885369A (en) * 1973-03-08 1975-05-27 Vigarex Ets Structural element
JPH02311639A (ja) * 1989-05-26 1990-12-27 Takenaka Komuten Co Ltd 合成床の構築方法
US5448866A (en) 1989-09-07 1995-09-12 Kajima Corporation Trusses and precast concrete slabs reinforced thereby
WO2011053103A2 (fr) * 2009-10-26 2011-05-05 Primeteh, A/S Béton composite pour dalles de sol et radiers

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
ANJA RIESE; SIEGFRIED DROESE: "Wohnhausdecken ohne obere Bewehrung - Belastungsversuche an neuartigen Deckenplatten", BETON-UND STAHLBETONBAU, vol. 91, 1996
WOLFGANG VOLKEL; ANJA RIESE; SIEGFRIED DROESE: "Neuartige Wohnhausdecken aus Stahlfaserbeton ohne obere Bewehrung", BETON-UND STAHLBETONBAU, vol. 93, 1998

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110183128A (zh) * 2019-06-05 2019-08-30 滁州市炬基节能新型建材有限公司 一种建筑垃圾再生高活性矿物掺合料及其制备
EP4005761A4 (fr) * 2019-07-22 2023-08-16 HPC Okinawa Co., Ltd. Béton précontraint
AU2020317713B2 (en) * 2019-07-22 2025-10-02 Hpc Okinawa Co.,Ltd. Prestressed concrete
CN110526646A (zh) * 2019-08-29 2019-12-03 徐州金盟新型建材有限公司 一种具有隔热功能的建筑构件
CN113185881A (zh) * 2021-05-10 2021-07-30 北京固斯特国际化工有限公司 一种针对混凝土烟囱的渗透反应型防腐材料及其应用
CN114577563A (zh) * 2022-02-11 2022-06-03 中国电建集团西北勘测设计研究院有限公司 一种自愈合混凝土裂缝修复检验方法

Also Published As

Publication number Publication date
SE543320C2 (en) 2020-11-24
NO20200060A1 (en) 2020-01-17
SE1930405A1 (en) 2019-12-16
NO348116B1 (en) 2024-08-26
LV15383A (lv) 2019-01-20
LV15383B (lv) 2019-10-20

Similar Documents

Publication Publication Date Title
Hadi et al. Axial and flexural behaviour of circular reinforced concrete columns strengthened with reactive powder concrete jacket and fibre reinforced polymer wrapping
Oskouei et al. Experimental study of the punching behavior of GFRP reinforced lightweight concrete footing
Hossain et al. Strength and fracture energy characteristics of self-consolidating concrete incorporating polyvinyl alcohol, steel and hybrid fibres
Farhan et al. Behaviour of ambient cured steel fibre reinforced geopolymer concrete columns under axial and flexural loads
NO348116B1 (en) Semi-precast elevated concrete element system
Iskhakov et al. High performance repairing of reinforced concrete structures
Vairagade et al. Strength of normal concrete using metallic and synthetic fibers
Abouhussien et al. Properties of semi-lightweight self-consolidating concrete containing lightweight slag aggregate
Khalil et al. Flexural strength of fibrous ultra high performance reinforced concrete beams
Naghibdehi et al. Repairing reinforced concrete slabs using composite layers
Hasnat et al. In-plane cyclic response of unreinforced masonry walls retrofitted with ferrocement
Cheah et al. The structural behaviour of HCWA ferrocement–reinforced concrete composite slabs
Allah et al. Geopolymer-and cement-based fabric-reinforced matrix composites for shear strengthening of concrete deep beams: Laboratory testing and numerical modeling
Qasim Behavior of reinforced reactive powder concrete slabs with openings
Nishiyama Mechanical properties of concrete and reinforcement state-of-the-art report on HSC and HSS in Japan
Shaheen et al. Characteristics of ferrocement lightweight wall
Maghsoudi et al. Moment redistribution and ductility of CFRP strengthened and non-strengthened unbonded post-tensioned indeterminate I-beams composed of UHSSCC
Al-Azzawi et al. A state of the art review on reactive powder concrete slabs
Ali et al. Strength evaluation of hybrid reinforced concrete columns under eccentric loads
Issani et al. High performance ECC floor slabs in coupled shear wall structures
Al-Azzawi et al. Behaviour of composite structural members built-up from locally available stone units jacketed with ferrocement
Aadithiya et al. Review paper on usage of ferrocement panels in lightweight sandwich concrete slabs
Resan et al. Behavior of multilayer ferrocement slab containing treated sponge layer core
EP3467226A1 (fr) Éléments de construction composites
Abouhussien et al. Influence of pouring techniques and mixture’s fresh properties on the structural performance of self-consolidating concrete beams

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18752627

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18752627

Country of ref document: EP

Kind code of ref document: A1