Structural surveys and diagnostics of structures
With whom does the Klokner Institute most frequently cooperate?
We greatly value every teamwork, both domestically and abroad. The opportunity to establish lucrative collaborations is seen as an opportunity to continually improve, learn about the latest testing procedures and methods, and in return contribute our own observations.
The Klokner Institute ČVUT most frequently cooperates with:
ROMANESQUE BRIDGE IN THE VYŠEHRAD NATIONAL CULTURAL MONUMENT GROUNDS
Under the Memorandum of Cooperation between the National Cultural Monument Vyšehrad and the Klokner Institute, diagnostics of the torso of a Romanesque bridge from the last third of the 11th century were carried out. The bridge is located at the site of the former royal acropolis and once connected the princely and royal precinct with the Romanesque basilica of St. Peter and Paul and was probably part of the fortification of the Přemyslid Palace. The torso of the bridge was uncovered during archaeological research in 1931. The aim of the work was to carry out diagnostics of the stone bridge itself and its static assessment with regard to the existing damage to the bridge vault, taking into account the mechanical properties of the stone and mortar determined by diagnostics, further to carry out diagnostics of the reinforced concrete ceiling structure above the Romanesque bridge, including static assessment, to evaluate the dynamic effects of traffic partially routed over the aforementioned reinforced concrete structure, and to evaluate the parameters of the internal environment based on the results of annual monitoring. From the findings and results, proposals and recommendations were formulated for measures aimed at maximally extending the service life of the Romanesque bridge torso.
Client: National Cultural Monument Vyšehrad
SPARTAKIAD STADIUM IN PRAGUE ON STRAHOV
Given the size of the stadium, the work was divided into five phases of diagnostic surveys, the aim of which was to assess the structural-technical condition of the stands, to carry out their static assessment taking into account the diagnostic results, and to determine their load-bearing capacity. The existing reinforced concrete stands date from different periods. The oldest is the west stand with adjacent arches from 1932–1938, about 10 years later the north and south stands were built for the XIth Sokol festival in 1948, and the youngest is the east stand with adjacent arches and eight external staircases built for the IVth Czechoslovak Spartakiad in 1975, which with its adjoining arches is already made of reinforced concrete prefabricated elements. In six visited archives, original project documentation was found only for the east stand (besides documentation of the steel structures of the gate frames), while for the other stands only fragments of documentation were found, generally not corresponding to the actual execution of the stands. The diagnostic surveys included in particular measurement of dimensions and shapes of structures, determination of concrete compressive strength, tensile strength of surface concrete layers, degree of concrete carbonation and water-soluble salt content, reinforcement of structural elements and assessment of the corrosion state of reinforcement, including corrosion risks for reinforcement, mechanical properties of reinforcement and structural steel, determination of floor and auditorium compositions, visual inspections and many other activities. The diagnostic results formed the main basis for the static analysis of the stands in the SCIA software and the determination of their load-bearing capacity. For each stand, proposals and recommendations for measures, remediation and repairs were formulated, aimed at minimizing irreversible degradation processes of the structures, since the future use of the stadium stands has not yet been decided.
Client: Capital City of Prague represented by Liga-servis, s.r.o.
JOSEF MÁNES BRIDGE
The Klokner Institute ČVUT in Prague carried out for Pontex s.r.o., which was the lead contractor, part of the diagnostic survey which included the activities described below. As part of the survey work and subsequent laboratory tests, the compressive strength and modulus of elasticity of the concrete of the load-bearing structure were determined, concrete and render tests and analyses, including freeze-thaw resistance, water absorption, resistance to chemical deicing agents, surface absorption, water-soluble salt content in concrete, identification of ASR of concrete aggregate by microscopic analysis and uranyl acetate test, analyses for determining the concrete mix ratio, aggregate granulometry and type of binder used, further thermal analyses of concrete and render were performed. As part of the survey, the thickness and composition of the road surfacing and tram track body and the condition of waterproofing were also investigated. Part of the work was also the so-called Reference Areas project, in which the possibility of using reprofiling materials and renders was verified both in-situ and in the laboratory. Since the load-bearing structure of the bridge consists of three-hinged arches, diagnostics of the granite hinge stones and endoscopic inspection of lead plates clamped between the hinge stones were carried out (the hinges contain a total of 312 lead plates). Part of the work was also a building-historical survey prepared by the Institute of Heritage Care of the Faculty of Architecture, ČVUT in Prague, in which the Klokner Institute also participated, and which besides the Josef Mánes Bridge also included its predecessor, i.e. the Iron Footbridge.
Client: Technical Road Administration of the Capital City of Prague, a.s.
DIVADLO NA VINOHRADECH
As part of the project for the reconstruction of the Divadlo na Vinohradech building, a structural-technical survey of selected reinforced concrete structures was carried out. The work focused on determining the compressive strength of concrete, reinforcement, corrosion state of reinforcement and corrosion risks for reinforcement, further on assessing the condition of the steel suspension of the ceiling from monier reinforcement above the auditorium and the corrosion state of the prestressing cables located in the auditorium floor, which ensure its stability.
ClientIng. arch. Petr Kolář
PALACE LIBEREC
For the purposes of the planned reconstruction of the Palace Liberec department store building, a structural-technical survey of the load-bearing structure of the building was carried out. The work focused on determining the compressive strength of concrete, the shape and reinforcement of the columns, the corrosion state of the reinforcement and corrosion risks for the reinforcement, the shape of selected foundation structures and other relevant facts for the static assessment of the structure. The results of the diagnostics were used as a basis for the static recalculation of the structures.
Client: UP Pardubice
ROMANSKY BRIDGE — already translated above (1910)
SMÍCHOV RAILWAY STATION
Client: For the construction project No. 44544 Smíchov Railway Station Terminal, diagnostics of the layers above underground structures were carried out, i.e. the thickness and composition of road surfacing and tram track body were determined, the condition of waterproofing was investigated, and the compressive strength of concrete of the load-bearing structure was determined. The results of the diagnostic work were used as a basis for the design of the reconstruction.
SUDOP Praha, a.s.
For the construction project No. 44544 Smíchov Railway Station Terminal, diagnostics of the layers above underground structures were carried out, i.e. the thickness and composition of road surfacing and tram track body were determined, the condition of waterproofing was investigated, and the compressive strength of concrete of the load-bearing structure was determined. The results of the diagnostic work were used as a basis for the design of the reconstruction.
Client: For the construction project No. 44544 Smíchov Railway Station Terminal, diagnostics of the layers above underground structures were carried out, i.e. the thickness and composition of road surfacing and tram track body were determined, the condition of waterproofing was investigated, and the compressive strength of concrete of the load-bearing structure was determined. The results of the diagnostic work were used as a basis for the design of the reconstruction.
RADOST BUILDING IN PRAGUE ON ŽIŽKOV
For the purposes of the planned adaptation of the Radost building (originally the General Pension Institute, later the House of Trade Unions), an extensive structural-technical survey divided into 3 main parts was carried out. Part 1 dealt with the reinforced concrete skeleton, for which the concrete strength, shape and reinforcement of structures, corrosion risks and corrosion state of reinforcement, shape of selected foundation structures and other relevant facts for the static assessment of the structure were determined. Part 2 dealt with the diagnostics of the RAKO ceramic cladding. As part of the diagnostics, tests were carried out to determine the mechanical and physical properties of the cladding (tensile and flexural tensile strength, adhesion to the substrate, water absorption, freeze-thaw resistance, thermal and moisture expansion, open porosity, resistance to sudden temperature change and microscopic analyses) and identification of types of cladding damage and their quantification. Based on the diagnostic results, an assessment of the cladding condition, prediction of residual service life and formulation of proposals and recommendations were carried out. Part 3 dealt with non-load-bearing structures. As part of the survey work, the compositions of the external envelope, floors and roof envelope were determined, a thermal-technical assessment of the external envelope and an assessment of the condition of internal floor tiles were carried out. A year later, supplementary diagnostics of selected ceiling structures were also carried out.
Client: QARTA ARCHITEKTURA, s.r.o.
SVATOPLUK ČECH BRIDGE
The Klokner Institute ČVUT in Prague carried out for the Faculty of Civil Engineering, ČVUT in Prague, which was the lead contractor, part of the diagnostic survey of the Svatopluk Čech Bridge, including work on a variant design for the reconstruction of the bridge deck. The diagnostic work carried out by the Klokner Institute focused on assessing the corrosion state of the railings and their PKO, the execution and condition of bridge bearings, piers and abutments, public lighting poles and decorative elements on the piers. In the variant design for the reconstruction of the bridge deck, the possibility of replacing the existing steel deck with a UHPC deck was assessed.
Client: Technical Road Administration of the Capital City of Prague
ŠKODA AUTO MLADÁ BOLESLAV
For the purposes of the reconstruction of the underground structure V12 in the Škoda Auto complex in Mladá Boleslav, diagnostics of the reinforced concrete structures of the monolithic skeleton of the structure were carried out. The aim of the work was to determine the compressive strength of concrete and the effect of oil products on its mechanical properties, the reinforcement of the structural elements of the skeleton, to determine the design characteristics of the reinforcement and to determine its corrosion state, including corrosion risks and mechanical properties of the reinforcement. Part of the diagnostics were also proposals and recommendations for the reconstruction of the structure.
Client: Novák & Partner
FRANTIŠEK PALACKÝ BRIDGE
The Klokner Institute ČVUT in Prague carried out for Inset s.r.o., which was the lead contractor, an extensive diagnostic survey of the structures of the František Palacký Bridge. The bridge was built in 1876–1878, simultaneously with part of the embankment on the Nové Město side. The bridge was built according to the design of Ing. J. Reiter and arch. B. Münzberger. In 1951 the bridge was widened with reinforced concrete cantilevers. The load-bearing structure consists of seven arches made of granite blocks with spans of 27.2 + 28.8 + 30.4 + 32.0 + 30.4 + 28.8 + 27.2 m and one brick arch on the Smíchov side with a span of 9.0 m. Part of the diagnostic work included load tests, static analyses taking into account the current condition of the bridge and the results of the diagnostic work, preparation of a building-historical survey, verification of restoration procedures in-situ and for the possible replacement of stones during repair, as well as the selection of suitable quarries, based on stone tests. The overall condition of the bridge was assessed, its load-bearing capacity was determined, proposals for measures for the bridge administrator were formulated, and a design for the reconstruction of the bridge was prepared.
Client: Technical Road Administration of the Capital City of Prague, a.s.
MAGISTRATE BUILDING OF HRADEC KRÁLOVÉ
The subject of the diagnostics was the RAKODUR ceramic cladding of the entrance portal of the magistrate building. As part of the work, a visual inspection of the cladding and classification of the identified damage was carried out, including a detailed record of defects per individual cladding tiles, acoustic tracing to identify the extent of areas where separation of the cladding from the substrate had already occurred, tests to detect microcracks in the glaze, and assessment of the condition of the jointing. Based on the findings, the current condition of the cladding was assessed and proposals and recommendations for the next period were formulated.
Client: Statutory City of Hradec Králové
ROMANESQUE BRIDGE IN THE VYŠEHRAD NATIONAL CULTURAL MONUMENT GROUNDS
The Klokner Institute ČVUT in Prague, in cooperation with Pontex s.r.o. and Inset s.r.o., carried out an extensive diagnostic survey of the Josef Hlávka Bridges V-010 and V-011. The old bridges across the Vltava and Štvanice Island (V-010) were built in 1910–1912 according to the design of Ing. František Mencl in the architectural design by arch. Pavel Janák. In 1958–1962, a bridge widening project was implemented, when shape-identical new bridges were built parallel to the old bridges, at a distance of approx. 3 m from the old bridges. The gap between the bridges was bridged by reinforced concrete transition slabs. The load-bearing structure of the old bridge across the Vltava consists of 3 arches (vaults) of plain concrete, designed as earth-filled three-hinged arches with clear spans of 36.0 m + 39.0 m + 36.0 m. Above the piers there are relieving reinforced concrete vaults resting on the main bridge vaults. The arches of both the main and relieving vaults are divided in the longitudinal direction into 3 separate vault strips, with the outer strips having a width of 4.95 m and the middle strip 6.0 m. As part of the work, a detailed diagnostic survey, static and dynamic load tests, static analyses taking into account the current condition of the bridge and the results of the diagnostic work, including the determination of the bridge load-bearing capacity, and installation of long-term temperature measurements in the bridge structures and measurement of movements in the hinges were carried out. The service life and resistance of the bridge structures were assessed and proposals and recommendations for the bridge administrator and the reconstruction designer were formulated. Part of the work was also a building-historical survey prepared by the Institute of Heritage Care of the Faculty of Architecture, ČVUT in Prague, in which the Klokner Institute also provided technical support.
Client: National Cultural Monument Vyšehrad
LIBEŇ BRIDGE
The subject of the set of diagnostics and static analyses carried out in 2015–2018 was the main bridge V-009 across the Vltava and the flood bridge X-656. In 2015, based on the submitted diagnostic inspections and project documentation, an analysis and assessment of the technical condition of the bridge group and the possibilities of repair or construction of a new bridge were carried out. In 2016, diagnostics and load tests of the X-656 bridge followed, including static analysis and determination of the load-bearing capacity of the vault and adjoining frame structures. At the turn of 2016 and 2017, a detailed diagnostics of the foundation and underwater part of the 3rd pier of the V-009 bridge was carried out. Throughout 2017, in cooperation with Pontex, s.r.o. and Inset, s.r.o., an extensive diagnostic survey of the V-009 bridge was carried out, including load tests, the result of which was the determination of the load-bearing capacity with regard to its identified current condition and the resulting necessary measures (a fundamental measure was the temporary propping of parts of the frame structures in emergency condition realized in February 2018), the possibilities of reconstruction, repairs and remedial interventions to ensure the load-bearing capacity and service life of the bridge according to current standards. Based on a recommendation arising from the diagnostic results of the V-009 bridge, diagnostics of the frame structures of the X-656 bridge was carried out at the beginning of 2018, including the determination of their load-bearing capacity and the load-bearing capacity of the X-656 bridge as a whole. The aim of the diagnostics of the reinforced concrete frame structures of the flood bridge X-656 of the Libeň bridge group was to assess the current condition of the frame structures, especially with regard to degradation effects, corrosion state of reinforcement and weakening of cross-sections of structural elements due to concrete degradation, to verify the reinforcement and dimensions of selected structural elements and to compare the findings with the data given in the available documents, and to verify the function and condition of the temporary propping of the joint of one of the frames, thereby creating a sufficient basis for the static assessment of the frame structures and the determination of their load-bearing capacity. The static assessment of the frame structures and the determination of their load-bearing capacity was carried out by the cooperating company Pontex, s.r.o.
Client: Technical Road Administration of the Capital City of Prague, a.s.
LEGION BRIDGE
Given the size of the stadium, the work was divided into five phases of diagnostic surveys, the aim of which was to assess the structural-technical condition of the stands, to carry out their static assessment taking into account the diagnostic results, and to determine their load-bearing capacity. The existing reinforced concrete stands date from different periods. The oldest is the west stand with adjacent arches from 1932–1938, about 10 years later the north and south stands were built for the XIth Sokol festival in 1948, and the youngest is the east stand with adjacent arches and eight external staircases built for the IVth Czechoslovak Spartakiad in 1975, which with its adjoining arches is already made of reinforced concrete prefabricated elements. In six visited archives, original project documentation was found only for the east stand (besides documentation of the steel structures of the gate frames), while for the other stands only fragments of documentation were found, generally not corresponding to the actual execution of the stands. The diagnostic surveys included in particular measurement of dimensions and shapes of structures, determination of concrete compressive strength, tensile strength of surface concrete layers, degree of concrete carbonation and water-soluble salt content, reinforcement of structural elements and assessment of the corrosion state of reinforcement, including corrosion risks for reinforcement, mechanical properties of reinforcement and structural steel, determination of floor and auditorium compositions, visual inspections and many other activities. The diagnostic results formed the main basis for the static analysis of the stands in the SCIA software and the determination of their load-bearing capacity. For each stand, proposals and recommendations for measures, remediation and repairs were formulated, aimed at minimizing irreversible degradation processes of the structures, since the future use of the stadium stands has not yet been decided.
Client: Technical Road Administration of the Capital City of Prague
KOLBENOVA, SMALL MACHINES HALL
The Klokner Institute ČVUT in Prague carried out for Pontex s.r.o., which was the lead contractor, part of the diagnostic survey which included the activities described below. As part of the survey work and subsequent laboratory tests, the compressive strength and modulus of elasticity of the concrete of the load-bearing structure were determined, concrete and render tests and analyses, including freeze-thaw resistance, water absorption, resistance to chemical deicing agents, surface absorption, water-soluble salt content in concrete, identification of ASR of concrete aggregate by microscopic analysis and uranyl acetate test, analyses for determining the concrete mix ratio, aggregate granulometry and type of binder used, further thermal analyses of concrete and render were performed. As part of the survey, the thickness and composition of the road surfacing and tram track body and the condition of waterproofing were also investigated. Part of the work was also the so-called Reference Areas project, in which the possibility of using reprofiling materials and renders was verified both in-situ and in the laboratory. Since the load-bearing structure of the bridge consists of three-hinged arches, diagnostics of the granite hinge stones and endoscopic inspection of lead plates clamped between the hinge stones were carried out (the hinges contain a total of 312 lead plates). Part of the work was also a building-historical survey prepared by the Institute of Heritage Care of the Faculty of Architecture, ČVUT in Prague, in which the Klokner Institute also participated, and which besides the Josef Mánes Bridge also included its predecessor, i.e. the Iron Footbridge.
Client: EDIFICE Development I, s.r.o.
KINO 64 U HRADEB
As part of the planned reconstruction of the cinema building, a structural-technical survey of selected reinforced concrete structures was carried out (concrete strength, reinforcement, corrosion state of reinforcement and corrosion risks for reinforcement), further the condition of the steel ceiling suspensions from monier reinforcement above the auditorium and the corrosion state of the prestressing cables located in the auditorium floor, which ensure its stability, were assessed.
Client: Tichý & Kolářová, s.r.o.
KOTVA DEPARTMENT STORE
The subject of the diagnostics of the Kotva department store in 2017 was the reinforced concrete structures, especially of the underground garages. The work focused on determining the reinforcement and corrosion state of the reinforcement of ceiling slabs and column heads, compressive strength of concrete, formulation of corrosion risks for reinforcement due to the action of chloride ions and the concrete carbonation process, determination of floor compositions, and assessment of the degree of damage to ceiling slabs by cracks. Based on the diagnostic results, recommendations for the remediation design were formulated. The diagnostic results were used as a basis for the static recalculation of the structures.
In 2018, diagnostics of the ceiling slab at ±0.0 m, i.e. the ceiling slab above the Albert store, which is below the plaza in front of the main entrance to the department store, was carried out. The work focused on determining the concrete strength, reinforcement of column heads, formulation of corrosion risks for reinforcement due to the action of chloride ions and the concrete carbonation process, and last but not least, verification of the parameters of the strengthening ceiling slab realized in 1992.
Client: Němec Polák, s.r.o., První nemovitostní, a.s.
HOTEL RAMADA AND NEOLUXOR IN PRAGUE
For the purposes of replacing the stone facade cladding and reconstructing the facade of the Ramada and Neoluxor hotel building, a structural-technical survey was carried out including visual inspection of the facade, determination of the structural solution and shape of the 2nd floor console and corner structures, measurement of the shape of the outer face of the load-bearing structure, determination of the thickness of the masonry parapet, internal monier reinforcement, and verification of the existence of a cavity in the parapet, determination of the corrosion state of exposed reinforcement of the load-bearing structure, and determination of the compressive strength of concrete. The output of the survey work was an assessment of the identified defects and the condition of the diagnosed structures, including outline proposals and recommendations.
MEOPTA PRAGUE KOŠÍŘE
Given the size of the stadium, the work was divided into five phases of diagnostic surveys, the aim of which was to assess the structural-technical condition of the stands, to carry out their static assessment taking into account the diagnostic results, and to determine their load-bearing capacity. The existing reinforced concrete stands date from different periods. The oldest is the west stand with adjacent arches from 1932–1938, about 10 years later the north and south stands were built for the XIth Sokol festival in 1948, and the youngest is the east stand with adjacent arches and eight external staircases built for the IVth Czechoslovak Spartakiad in 1975, which with its adjoining arches is already made of reinforced concrete prefabricated elements. In six visited archives, original project documentation was found only for the east stand (besides documentation of the steel structures of the gate frames), while for the other stands only fragments of documentation were found, generally not corresponding to the actual execution of the stands. The diagnostic surveys included in particular measurement of dimensions and shapes of structures, determination of concrete compressive strength, tensile strength of surface concrete layers, degree of concrete carbonation and water-soluble salt content, reinforcement of structural elements and assessment of the corrosion state of reinforcement, including corrosion risks for reinforcement, mechanical properties of reinforcement and structural steel, determination of floor and auditorium compositions, visual inspections and many other activities. The diagnostic results formed the main basis for the static analysis of the stands in the SCIA software and the determination of their load-bearing capacity. For each stand, proposals and recommendations for measures, remediation and repairs were formulated, aimed at minimizing irreversible degradation processes of the structures, since the future use of the stadium stands has not yet been decided.
HOTEL EVROPA IN PRAGUE
As part of the planned reconstruction of the Art Nouveau building of the Hotel Evropa (formerly Hotel Šroubek), a structural-technical survey of the ceiling structures was carried out in order to determine their structural and material solution, compositions, dimensions and arrangement of load-bearing elements. As part of the survey work, diagnostics of the wooden roof truss and wooden elements of the ceiling structures were carried out, including proposals and recommendations for wood remediation.
TESLA PRAGUE HOLEŠOVICE
The Klokner Institute ČVUT already carried out the first structural-technical survey of the M3 building in 2006. At that time, the work focused on the reinforced concrete structures of the above-ground floors, especially prestressed beams and ceiling panels, reinforced concrete monolithic ceiling slabs and columns, including the determination of the mechanical properties of concrete. The subject of two further structural-technical surveys carried out in 2017 were the foundation structures, i.e. determination of the structural solution and shape of the foundations, including the foundation depth. Furthermore, the external envelope made of panels was investigated, especially the method of its anchoring to the load-bearing structure and the mutual connection of the external, respectively parapet panels. Last but not least, the compositions of floors and the roof envelope were determined. The results of the survey work were used as a basis for the design of the reconstruction of the building.
COMPLEX OF THE PRAGUE PUBLIC TRANSPORT COMPANY IN HLOUBĚTÍN
The structural-technical survey of the buildings in the complex of the Public Transport Company of the Capital City of Prague, Electrical Tramways, which are designated for demolition, focused on the identification of hazardous materials in building structures and their components. With regard to the character of the buildings, the purpose of their use and the classification of hazardous materials especially according to Act 185/2001 and 229/2014 Coll. and decrees of the Ministry of the Environment 93/2016 Coll., MoE and MoH 94/2016 Coll., MoE 383/2001 Coll. and MoE 294/2005 Coll., the survey work was concentrated mainly on finding materials containing asbestos and tar, and further materials contaminated with oil products, respectively mercury.
