Joint Bearing Capacity Testing Service – Accredited Evaluation of Connection Strength and Stiffness for Structural and Mechanical Assemblies on the Czech Market
Our internationally accredited laboratory delivers a comprehensive joint bearing capacity testing service that provides Czech construction companies, steel fabricators, timber frame manufacturers, fastener importers and mechanical engineering firms with the independent, legally defensible data they need to verify the strength, stiffness and failure behaviour of structural connections. All tests are conducted within the rigorous framework of ISO/IEC 17025, and every report bearing the ILAC mark is unconditionally accepted by the Czech Trade Inspection Authority, the Technical Inspection of the Czech Republic, local building authorities and all notified bodies across the European Union. A correctly executed joint bearing capacity testing service determines the maximum load a connection can carry, the deformation under service conditions, the slip modulus, and the failure mode – whether bearing failure of the plate, shear fracture of the fastener, splitting of the timber, or pull-out of the anchor. This data is essential for demonstrating conformity with the Eurocodes, for CE marking of structural components under the Construction Products Regulation, and for obtaining national technical approvals in the Czech Republic.
Product Samples and Connection Types We Regularly Subject to Joint Bearing Capacity Testing
Our servo-hydraulic and electromechanical testing machines can accommodate specimens from small single-fastener coupons to full-scale truss nodes. The following categories represent the most frequently tested items:
- Steel connections and steelwork assemblies – bolted end plates, fin plates, splice plates, gusset plates, pin connections, and welded beam-to-column joints
- Timber connections and engineered wood assemblies – nailed, screwed, dowelled and split-ring connectors, truss plates, glued-in rods and cross-laminated timber panel joints
- Fasteners and anchoring systems – bolts, screws, nails, dowels, studs, rivets, and post-installed anchors in concrete and masonry
- Aluminium and lightweight metal connections – bolted and welded joints in aluminium frames, curtain wall brackets and solar mounting systems
- Precast concrete connections and grouted joints – beam-to-column joints, column splices and wall panel connections
- Composite and mixed-material connections – steel-to-timber, aluminium-to-steel, and fibre-reinforced polymer-to-metal joints
- Connections in cold-formed steel structures – self-tapping screw and blind rivet joints in thin-walled profiles for racking and modular buildings
- Mechanical and automotive connections – bolted flanges, shaft-hub connections, press fits, and pin joints in machinery
Steel Connections – Joint Bearing Capacity Testing Service According to EN 1993-1-8, EN 1090 and Related Standards
- Tensile and shear testing of bolted connections according to ČSN EN 1993-1-8 and ČSN EN ISO 6892-1 principles: specimens representing single-bolt or multi-bolt lap joints are loaded in tension or shear until failure. The bearing resistance of the plates, the shear resistance of the bolts, and the net section resistance are measured and compared with the design values calculated from the characteristic strengths. The load-deformation curve is recorded, and the initial stiffness and the deformation at the serviceability limit state are reported. This test is routinely requested by Czech steel fabricators to qualify bolt grades and connection geometries for building and bridge structures.
- Welded joint tensile and bend testing according to ČSN EN ISO 4136 and ČSN EN ISO 5173: cruciform and T-joint specimens are subjected to tensile loading to evaluate the strength of fillet and butt welds. The weld throat thickness and the fracture location – in the weld metal, in the fusion line or in the base material – are documented, and the bearing capacity of the welded joint is compared with the design weld strength prescribed in the fabrication specification.
- Fin plate and end plate connection testing under combined shear and tension: full-scale beam-to-column connection assemblies are loaded in a test frame that applies both a vertical shear force and a horizontal tension. The moment-rotation characteristic, the bolt force distribution and the limit states – bolt shear, plate bearing, weld fracture and local buckling – are evaluated. This joint bearing capacity testing service supports Czech designers in validating the resistance tables used in structural steelwork software.
- Slip-resistant connections with preloaded bolts according to ČSN EN 1090-2 and EN 14399: the slip factor of the faying surfaces is determined by testing a symmetrical double-lap joint under tension. The load at which a sudden displacement of 0.15 mm occurs is recorded, and the slip factor is calculated. For Czech infrastructure projects, this value is a mandatory input for connections designed to resist fatigue and vibration.
- Pin connection and clevis testing for tension rods and bracing systems: a pin-loaded plate specimen is pulled to failure to determine the bearing capacity of the pin hole. The effect of edge distance, hole clearance and plate thickness on the ultimate load is investigated, and the results are used to design tension systems for roofs, stadia and footbridges in the Czech Republic.
Timber and Engineered Wood Connections – Joint Bearing Capacity Testing According to EN 383, EN 1995-1-1 and EN 26891
- Embedment strength of timber and wood-based panels according to ČSN EN 383 and ASTM D5764: a smooth dowel or a screw shank is pressed into the edge or face of a timber specimen, and the load-deformation curve is recorded. The embedment strength in N/mm² is calculated from the load at 5 mm deformation. This fundamental material property governs the bearing capacity of all dowel-type timber connections, and it is determined for the specific timber species and fastener diameter used by Czech timber frame manufacturers.
- Load-slip behaviour and bearing capacity of single-fastener timber joints according to ČSN EN 26891: a double-shear joint with a single dowel, nail, screw or bolt is loaded under a controlled protocol that includes a preload cycle and a final loading to failure. The slip modulus Ks, the yield load and the maximum load are reported. The test is repeated for multiple specimens, and the characteristic bearing capacity is calculated according to the statistical procedures of EN 1995-1-1 for use in the design of trusses, beams and panelised systems.
- Testing of multiple-fastener connections and group effects: joints with several fasteners in a row or a staggered pattern are loaded to failure. The reduction in the average load per fastener compared with the single-fastener value is determined, and the effective number of fasteners for the design equations is validated. This research is regularly commissioned by Czech manufacturers of nail plates and truss connectors.
- Glued-in rod and bonded-in fastener connections: threaded steel rods or glass-fibre reinforced polymer rods are bonded into glulam or LVL blocks with an epoxy or polyurethane adhesive, and the assembly is pulled to failure. The pull-out force, the bond shear strength and the failure mode – wood shear, adhesive-cohesive failure or rod yielding – are reported. This joint bearing capacity testing service is essential for the certification of moment-resisting connections in large-span timber halls and bridges.
- Truss plate and punched metal plate fastener testing: a tooth-plate connector is pressed into two timber members, and the assembly is tested in tension, shear or moment. The load-slip behaviour and the ultimate load are recorded, and the connection strength is compared with the values declared by the plate manufacturer. Czech truss rafter producers use this test to qualify new plate designs and timber species combinations.
Anchors, Fasteners and Post-Installed Connections in Concrete and Masonry – Joint Bearing Capacity Testing According to ETAG 001, EAD and EN 1992-4
- Tensile pull-out testing of mechanical and chemical anchors according to ETAG 001 Annex A and ČSN EN 1992-4: a single anchor is installed in a concrete or masonry block and loaded in tension to failure. The ultimate pull-out force, the load-displacement curve and the failure mode – cone breakout, bond failure, steel rupture or pull-through – are determined. For Czech importers of anchor systems, this test provides the characteristic resistance data required for the European Technical Assessment.
- Shear testing of anchors and fasteners at the concrete edge: the anchor is loaded in shear perpendicular to the free edge at a defined edge distance. The shear capacity, the concrete edge breakout load and the influence of the anchor embedment depth are recorded. The results are used by Czech structural engineers to specify the minimum edge distance and spacing for anchor groups in column base plates and façade fixings.
- Combined tension and shear loading of anchor groups: a rigid base plate fixed with two or four anchors is loaded simultaneously in tension and shear at various angles to determine the interaction diagram. This test validates the design assumptions of ČSN EN 1992-4 for anchor groups subjected to seismic or wind loading on Czech high-rise and industrial buildings.
- Seismic shear and tension testing of anchors according to ETAG 001 Annex E and EAD 330232: the anchor is subjected to pulsating or alternating load cycles that simulate seismic action. The displacement amplitude and the number of cycles to failure are recorded. This joint bearing capacity testing service provides the seismic performance category C1 or C2 for anchors installed in structures in seismically active regions of the Czech Republic.
- Testing of post-installed reinforcing bar connections: rebars are post-installed into existing concrete with a chemical mortar and loaded in tension. The yield and ultimate bond strengths are measured, and the results are compared with the design values for cast-in reinforcement. Czech renovation and strengthening contractors use this test to verify the connection between new and existing concrete elements.
Report Acceptance and Regulatory Compliance for the Czech Republic
All measurements performed within our joint bearing capacity testing service are executed under the fully accredited scope of our ISO/IEC 17025 quality management system. Each test report that carries the ILAC mark is therefore recognised automatically by the Czech Trade Inspection Authority, the Technical Inspection of the Czech Republic, local building authorities and all notified bodies in the European Union. For Czech steel fabricators, timber construction companies, fastener suppliers and precast concrete manufacturers, these reports constitute legally robust evidence that the connections meet the structural requirements of the applicable Eurocodes and product standards. The documentation can be directly used to issue inspection certificates according to ČSN EN 10204, to support CE marking under the Construction Products Regulation, to obtain national technical approvals, and to resolve disputes concerning the load-bearing performance of structural joints.
