BS EN 26891-1991 (2000) ISO 6891-1983 PDF

Full title and description

STB BS EN 26891-1991 (2000) — Timber structures. Joints made with mechanical fasteners. General principles for the determination of strength and deformation characteristics (identical to ISO 6891:1983). This document gives general principles and test practices for determining the load-bearing strength and slip/deformation behaviour of timber joints that use mechanical fasteners, to allow reproducible comparison of results between laboratories and to provide a basis for more detailed standards for particular fastener types.

Abstract

This standard establishes specimen conditioning, measurement, loading procedures and reporting rules for static tests on joints made with mechanical fasteners in timber structures. It defines measured parameters (loads, slips), required measurement accuracy, staged preloading and loading regimes, methods to estimate maximum load, and procedures for presenting results such as maximum load, slip modulus and failure modes. It is the EN implementation of ISO 6891:1983 and has been adopted/published in national catalogues (BS EN 26891:1991; listed in some national adoptions, including an STB listing dated 2000).

General information

• Status: Published as EN 26891:1991 and adopted as BS EN 26891:1991; also appears in national catalogues (STB listing dated 2000). Users should confirm current national status and any amendments with their national standards body.
• Publication date: EN/BS publication 1991 (BS EN 26891:1991 — original ISO counterpart ISO 6891:1983).
• Publisher: CEN/ISO (ISO 6891:1983 is the international original); British Standards Institution for the BS EN version; national adopters (STB) for the 2000 listing.
• ICS / categories: 91.080.20 — Timber structures.
• Edition / version: EN 26891:1991 (corresponding to ISO 6891:1983). National listing STB … (2000) indicates a 2000 national adoption/availability entry.
• Number of pages: Typically published as a short technical standard (around 12 pages in the BSI edition).

Scope

The standard applies to joints made with mechanical fasteners used in statically loaded timber structures. It provides general principles for test specimen manufacture and conditioning, required measurement accuracy (load and slip), loading and preloading sequences, determination/estimation of maximum load, and methods for recording and reporting results so that tests are reproducible and comparable. Detailed procedures for specific fastener types (nails, bolts, punched metal plates, etc.) are intended to be contained in separate standards.

Key topics and requirements

• Specimen conditioning to standard atmospheres (reference to ISO 554) to ensure realistic moisture content and environmental conditions during testing.
• Measurement accuracy: load measurement to about ±1% and slip measurement to ±1% or ±0.02 mm for small displacements; equipment must prevent eccentricities and twisting affecting slip readings.
• Loading procedure: staged preloading and cyclic or stepped loading starting from a fraction of the estimated maximum load, holding periods, and continued loading until failure or a defined slip limit (typical reference 15 mm).
• Calculation of characteristic parameters: maximum load, slip at defined loads, slip modulus (stiffness), settlement and adjustment procedures when the estimated maximum load is updated during testing.
• Test reporting requirements: timber species and density, moisture content, fastener type and coating, joint geometry, specimen preparation, test apparatus and accuracy, loading regime, observed failure modes and full test data.

Typical use and users

Used by structural timber engineers, research and development laboratories, test houses, fastener manufacturers, building product certification bodies, and designers concerned with the mechanical performance of connections in timber structures. It is employed to generate comparable test data for design, product development, quality control and regulatory compliance of timber joints with mechanical fasteners.

Related standards

ISO 6891:1983 (original international text) is the basis. The standard refers to ISO 554 (standard atmospheres for conditioning/testing). Complementary or subsequent EN/ISO standards cover test methods for specific fasteners (nails, bolts, punched metal plate fasteners) and product-specific design rules; national adoptions and later EN standards for specific joint types should be consulted where applicable.

Keywords

Timber structures; mechanical fasteners; joints; slip; deformation; strength; test methods; specimen conditioning; slip modulus; loading procedure; BS EN 26891; ISO 6891.

FAQ

Q: What is this standard?

A: It is a test-method/principles standard titled "Timber structures — Joints made with mechanical fasteners — General principles for the determination of strength and deformation characteristics" (EN 26891:1991), which corresponds to ISO 6891:1983 and has been published/adopted in national catalogues (BS EN 26891:1991; STB listing 2000).

Q: What does it cover?

A: It covers specimen conditioning, measurement accuracy for load and slip, staged preloading and loading regimes, procedures to estimate/measure maximum load and slip behaviour, calculation of slip modulus and other characteristic parameters, and required reporting to ensure reproducible test results.

Q: Who typically uses it?

A: Structural timber engineers, test laboratories, fastener manufacturers, researchers, certification and approvals bodies, and designers who need valid, comparable data on the strength and deformation behaviour of mechanically fastened timber joints.

Q: Is it current or superseded?

A: The document was published as EN 26891:1991 and is the EN counterpart of ISO 6891:1983; some national catalogues list an STB entry dated 2000 for availability. National status (current, withdrawn or superseded, and any amendments) can change — always verify with the relevant national standards body (BSI, ASRO/STB or your national member body) for the authoritative current status and any later replacements or amendments.

Q: Is it part of a series?

A: It is a general/principles standard intended to be complemented by separate, more detailed standards for particular fastener types and joint configurations. It cross-references standards such as ISO 554 for conditioning and points to future or companion standards that define test setups for nails, bolts, punched metal plate fasteners and similar components.

Q: What are the key keywords?

A: Timber joints, mechanical fasteners, strength, deformation, slip, slip modulus, specimen conditioning, static loading, test procedure, BS EN 26891, ISO 6891.