Glulam Design Software for Eurocode 5

Supplier & Code Integration

Effective glulam beam design begins with the correct application of Eurocode material parameters and load factors. Our platform integrates supplier-specific glulam data with Eurocode 5 requirements, enabling fast and reliable structural verification of timber beam elements.

Material grades such as GL24h, GL28h, and others are evaluated using Eurocode 5 design parameters, while national annex settings ensure compatibility with country-specific safety factors and load combinations.

Analytical Model for Glulam Beams

• Elastic Beam Theory
Glulam beams are analyzed using classical Euler–Bernoulli beam theory. The beam is treated as a linear elastic element where plane sections remain plane during bending. This approach provides accurate evaluation of internal forces, stresses, and deflections.

• Section Properties
The structural behavior is determined from the beam geometry and material grade. Key properties such as moment of inertia, section modulus, effective area, and radius of gyration are automatically calculated to evaluate stiffness and strength.

• Stability Considerations
Slender beams may experience lateral-torsional instability when subjected to bending. The design incorporates effective length parameters and stability checks to ensure reliable structural performance.

Structural Performance Checks

The calculator evaluates the main structural limit states according to Eurocode 5 provisions.

• Bending Resistance
Verification of bending stresses against the design bending strength of the glulam section. The tool calculates the maximum bending moment and corresponding stress utilization.

• Shear Resistance
Shear stresses within the beam cross-section are checked against the design shear strength to ensure the beam can safely transfer vertical loads.

• Torsional Stability Check Due to Bending
Glulam beams may experience lateral-torsional buckling when bending about the major axis. The calculator evaluates the critical bending stress and stability reduction factors to verify safe behavior under bending.

• Deflection Verification
Serviceability performance is assessed by calculating instantaneous, creep, and final deflections. The resulting deformation is compared against allowable span limits to ensure adequate stiffness and occupant comfort.

Supplier & Code Integration

Effective glulam column design begins with the correct application of Eurocode material parameters and load factors. Our platform integrates supplier-specific glulam data with Eurocode 5 requirements, enabling fast and reliable structural verification of timber compression members.

Material grades such as GL24h, GL28h, and others are evaluated using Eurocode design parameters. National Annex settings allow the calculator to automatically apply country-specific safety factors, load combinations, and design coefficients.

Analytical Model for Glulam Columns

• Elastic Member Analysis
Glulam columns are modeled as linear elastic members following classical structural mechanics principles. Axial compression forces, bending moments caused by eccentric loads, and interaction effects are evaluated using Eurocode 5 design procedures.

• Section Properties
The structural behavior is determined from the column geometry and timber grade. Important properties such as section modulus, moment of inertia, and radius of gyration are automatically calculated to determine the stiffness and resistance of the member.

• Load Eccentricity Effects
Columns frequently experience eccentric loading from beams or connection details. The calculator considers eccentricities in both principal directions, resulting in bending moments that are combined with axial compression during design verification.

Structural Performance Checks

The calculator evaluates the key ultimate limit state checks for timber columns according to Eurocode 5.

• Bending Verification
Bending stresses caused by load eccentricities are checked about both the major and minor axes of the column cross-section. The calculated stresses are compared with the design bending strength of the glulam member.

• Compression Verification
Axial compression forces acting on the column are verified against the design compression strength of the material. This ensures the column can safely carry vertical loads transferred from beams and upper structural elements.

• Combined Actions Verification
When axial force and bending moments occur simultaneously, the interaction between these actions is checked according to Eurocode design interaction equations. This combined check ensures safe behavior under realistic loading conditions.

• Buckling Verification
Slender columns are susceptible to instability. The calculator evaluates column buckling using effective length factors, slenderness ratios, and reduction factors to determine the design buckling resistance.

• Lateral Torsional Stability
Additional stability verification ensures that the column remains stable under combined compression and bending effects, considering the orientation of loads and support restraints.

Supplier Integration & Material Data

Effective glulam member design begins with accurate material properties and section parameters. Our platform integrates supplier-specific glulam data, enabling reliable verification of timber structural members under combined loading conditions.

Material grades such as GL24h, GL28h, and others are evaluated using Eurocode 5 material parameters to determine the strength and stiffness properties of the timber member.

Analytical Model for Glulam Members

• Design Action Effects
Unlike other calculators that derive internal forces from loads and spans, this tool directly evaluates design forces provided by the user. Bending moments, shear forces, and axial forces are entered as design action effects and used directly for structural verification.

• Section Properties
The structural response is determined from the cross-section geometry and timber grade. Section modulus, moment of inertia, and other section properties are used to evaluate stresses and resistance.

• Member Configuration
The calculator supports different member roles such as columns or diagonal braces. Member length, analysis location, and loading duration are considered when evaluating structural performance.

Structural Performance Checks

The calculator evaluates the key ultimate limit state checks according to Eurocode 5 provisions.

• Bending Verification
Bending stresses are checked about both principal axes using the applied design bending moments Mx and My.

• Combined Bending Check
When bending occurs simultaneously about both axes, the interaction between the two bending components is evaluated to ensure safe combined bending resistance.

• Compression Verification
Axial compression forces applied to the member are checked against the design compression resistance of the glulam section.

• Combined Bending and Compression
When axial compression and bending occur together, interaction equations are used to verify the combined stress condition.

• Shear Verification
Shear forces Fx and Fy acting in both principal directions are checked against the design shear resistance of the member.

• Combined Actions Check
The calculator evaluates the interaction between shear, bending, and axial forces to ensure safe structural performance under multiple simultaneous internal forces.

• Stability Verification
Member stability is assessed using effective length and slenderness parameters to ensure the member remains stable under combined loading effects.

Advanced GLT Fire Engineering

Structural fire design for glulam members is a critical component of any Eurocode-based structural verification and performance-based fire engineering solution.

SPEC Toolbox simplifies fire verification for glulam beams and columns by implementing Eurocode 5 fire design provisions and national annex methodologies. The platform evaluates structural resistance under fire exposure by calculating char depth development and the reduced effective cross-section, ensuring that glulam members maintain sufficient load-bearing capacity during the required fire resistance period.

Whether using standardized Eurocode fire design parameters or project-specific material properties, the calculator determines the residual section and evaluates the structural capacity of glulam members to meet Eurocode safety and structural integrity requirements.

Precision Charring and Residual Section Analysis

Our engine models the physical process of timber charring during fire exposure, enabling accurate determination of the remaining structural cross-section.

Users can define the basic charring rate β₀ and notional charring rate βₙ, together with the required fire resistance time. Based on these parameters, the platform calculates char depth and the effective residual section after fire exposure.

The calculator also accounts for different exposed faces and protection conditions, allowing engineers to simulate realistic fire scenarios such as partial exposure, protected faces, or multi-sided fire attack. This ensures reliable structural verification for glulam members subjected to fire.

Automated Fire Verification for Structural Safety

To provide transparent and reliable fire engineering solutions, SPEC Toolbox automates the calculation of Eurocode fire design checks for glulam members.

The platform evaluates the structural capacity of the reduced cross-section after charring and verifies key resistance mechanisms including:

• Fire Bending Resistance

• Fire Shear Resistance

• Torsional Stability Under Fire Conditions

This automated verification ensures that glulam members maintain sufficient structural performance throughout the specified fire duration, helping engineers design safe and efficient timber structures under fire exposure.

Advancing Structural Connection Design for Glulam

While Eurocode 5 (EN 1995-1-1) provides the fundamental design framework for timber structures, modern glulam connection design often requires more advanced modeling and product-specific performance data to ensure reliable structural performance.

Advanced Yield Modeling:
SPEC Toolbox implements the Eurocode Johansen Yield Models to accurately evaluate the behavior of dowel-type fasteners in glulam connections, ensuring precise prediction of failure modes and load-carrying capacity.

ETA Integration:
Our platform integrates supplier-specific European Technical Assessments (ETAs), enabling engineers to design connections using certified fasteners and manufacturer-verified performance data.

Simplified Structural Joint Design

SPEC Toolbox streamlines complex connection calculations into a clear and efficient engineering workflow for common glulam connection scenarios.

Preconfigured Connection Types:
Design and verify a wide range of glulam connection configurations including:

• Dowel and Bolt Connections

• Beam-to-Column Connections

• Beam-to-Beam Connections

• Compression Perpendicular to Grain (GLT)

• Beam Notch Verification

• Shear Reinforcement Design

• CLT Floor-to-Beam Interfaces

Each module automatically checks the relevant geometry constraints, load transfer mechanisms, and failure modes according to Eurocode design provisions.

The “Global-Local” Connection Library

SPEC Toolbox allows engineers to combine glulam suppliers with industry-leading fastener manufacturers, enabling realistic connection design that reflects both material properties and hardware performance.

Universal Fastener Selection:
Choose from top-tier fastening systems including ESSVE, Eurotec, Klimas, Rocket/Vynex, Rothoblaas, Schmid Schrauben, Sihga, SPAX, Würth, and Pitzl.

Verified Compatibility:
Connection designs can be evaluated with glulam materials from leading European suppliers including Binderholz, Kalvasta Timber, MTT, and Theurl, ensuring accurate structural verification using real manufacturer data.

Advanced Design for Penetrations in Glulam Members

Openings and service penetrations in structural glulam beams introduce localized stress concentrations that must be carefully evaluated to ensure structural safety.

While Eurocode 5 (EN 1995-1-1) provides the foundation for timber design, modern building systems frequently require multiple beam penetrations for mechanical, electrical, and plumbing services. SPEC Toolbox enables engineers to assess these modifications while maintaining the structural integrity of the beam.

The platform evaluates circular and rectangular penetrations, accounting for their size, location, and interaction with the beam’s stress distribution to ensure reliable structural verification.

Detailed Penetration Geometry and Structural Assessment

SPEC Toolbox allows engineers to define multiple penetrations along the beam span, enabling accurate modelling of real service routing scenarios.

Flexible Penetration Geometry:
Users can define penetration type, dimensions, and position along the beam, including:

• Circular or rectangular openings

• Penetration size and spacing

• Location within the beam cross-section

• Reinforced or unreinforced openings

The platform automatically evaluates geometric limitations and spacing requirements, ensuring compliance with design rules for timber beams containing openings.

Reinforcement and Structural Capacity Verification

To maintain structural safety, the calculator evaluates the residual structural capacity of the beam after penetration introduction.

Reinforcement Integration:
Where required, the platform allows the use of self-tapping screws as reinforcement elements, helping redistribute stresses around openings and prevent brittle failure modes.

Automated Structural Checks:
The system verifies the structural performance of the beam by evaluating:

• Geometric Limitations for Penetrations

• Tension Verification for Unreinforced Openings

• Flexural Resistance of the Modified Section

• Shear Resistance Near Penetrations

• Reinforcement Geometry Requirements

• Reinforcement Design Capacity

This automated verification ensures that glulam beams with penetrations maintain sufficient structural performance under applied loads while meeting modern service integration requirements.

If you’re looking to design CLT on your next project, then SPEC Toolbox has you covered!