SIST EN 14731:2006

Execution of special geotechnical works - Ground treatment by deep vibration

his European Standard is applicable to the planning, execution, testing and monitoring of ground treatment by deep vibration achieved by depth vibrators and compaction probes.
The following types of treatment are covered by this European Standard:
   deep vibratory compaction to densify the existing ground;
   vibrated stone columns to form a stiffened composite ground structure by the insertion of granular material which itself shall be densified. Generally, stone columns have a diameter greater than 0,6 m and lower than 1,2 m.
The following treatment methods are covered by this European Standard:
   methods in which depth vibrators, containing oscillating weights which cause horizontal vibrations, are inserted into the ground;
   methods in which compaction probes are inserted into the ground using a vibrator which remains at the ground surface and which in most cases oscillates in a vertical mode.
Treatment methods are outlined in Annexes A and B.
The following treatment methods, among others, are not included in this European Standard:
   methods in which sand or stone columns are installed by means of impact or top vibratory driven casing;
   methods in which very stiff columns are formed either by the addition of cement to granular material or by the use of concrete or any other binder;
   dynamic compaction and other methods in which some form of treatment is applied to the ground surface;
   explosive compaction.

Ausfürung von besonderen geotechnischen Arbeiten (Spezialtiefbau) - Baugrundverbesserung durch Tiefenrüttelverfahren

Exécution de travaux géotechniques spéciaux - Amélioration des massifs de sol par vibration

La présente Norme européenne s�applique à l�organisation, à l�exécution, au suivi et au contrôle des travaux
d�amélioration des massifs de sol par vibration réalisés à l�aide de vibreurs de profondeur (ou vibreurs torpilles) ou
de profilés vibrants.
La présente Norme européenne recouvre les types de traitement suivants :
- les traitements par vibration profonde (ou vibrocompactage) réalisés pour augmenter la densité d�un massif de
terrain existant ;
- les traitements par colonnes ballastées vibrées réalisés pour renforcer un massif de terrain en insérant des
colonnes de matériaux granulaires compactés par vibration. En règle générale, les colonnes ballastées ont un
diamètre compris entre 0,6 m et 1,2 m.
La présente Norme européenne recouvre les procédés de traitement suivants :
- les procédés consistant à insérer dans le terrain des vibreurs de profondeur (ou vibreurs torpilles), comportant
des masses oscillantes qui provoquent des vibrations horizontales ;
- les procédés consistant à insérer dans le terrain des profilés vibrants transmettant à celui-ci les oscillations
d�un vibreur de tête qui, le plus souvent, provoque des vibrations verticales.
Les procédés de traitement sont présentés dans les Annexes A et B.
La présente Norme européenne ne porte pas, entre autres, sur les procédés de traitement suivants :
- les procédés consistant à réaliser des colonnes de sables ou de pierres par pilonnage direct ou à l�aide d�un
tube de fonçage vibré en tête ;
- les procédés consistant à réaliser des colonnes très raides en malaxant les terrains granulaires avec du
ciment ou du béton ;
- le compactage dynamique (ou pilonnage) et les autres méthodes dans lesquelles le compactage est effectuée
depuis la surface du terrain ;
- le compactage par explosifs.

Izvedba posebnih geotehničnih del – Temeljenje z globinsko vibracijo

General Information

• Status: Published
• Publication Date: 31-Jan-2006
• ICS: 93.020 - Earthworks. Excavations. Foundation construction. Underground works
• Technical Committee: KON - Structures
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Feb-2006
• Due Date: 01-Feb-2006
• Completion Date: 01-Feb-2006
• Ref Project: EN 14731:2005 - Execution of special geotechnical works - Ground treatment by deep vibration

Overview

EN 14731:2005 (CEN) specifies requirements for the planning, execution, testing and monitoring of ground treatment by deep vibration. It covers two principal treatment types:

• Deep vibratory compaction - densification of existing granular ground to increase strength, stiffness and reduce permeability/liquefaction risk.
• Vibrated stone columns - formation of stiffened composite soil/column ground by inserting and densifying granular material (commonly 0.6 m–1.2 m diameter).

The standard addresses methods using depth vibrators (horizontal oscillation) and compaction probes driven from a top vibrator (typically vertical mode). Informative Annexes A and B describe treatment methods. Several methods are explicitly excluded (e.g., dynamic/explosive compaction, impact-driven columns, stiff cement- or concrete-bound columns).

Key topics and technical requirements

EN 14731 focuses on practical and safety-critical aspects of geotechnical works by deep vibration:

• Scope of work: planning, execution, testing, monitoring and record-keeping for vibro compaction and vibrated stone columns.
• Equipment & methods: depth vibrators, compaction probes, and the dry top-feed, wet and dry bottom-feed stone column processes (Annex B).
• Geotechnical investigation: required extent and depth per EN 1997‑1 and prEN 1997‑2 to identify treatable granular layers, hard strata, groundwater and contaminants.
• Materials: specification and quality control for imported sands, gravels or crushed aggregates; durability and chemical inertness requirements.
• Design considerations: selection of treatment method, verification, layout, extent, sequencing and effect of intervening layers (clays, silts, organics).
• Execution controls: site preparation, setting out, treatment procedure and adaptations for obstructions or unsuitable zones.
• Supervision, testing & monitoring: in-process testing, instrumentation, acceptance criteria and final records.
• Health, safety & environment: safety standards for drilling/piling equipment and environmental protection measures and impact on adjacent structures.

Applications and users

EN 14731 is intended for anyone responsible for delivering or regulating deep-vibration ground improvement:

• Geotechnical and structural engineers (design verification and method selection)
• Site contractors and equipment operators (execution and quality control)
• Project managers and client representatives (specification and acceptance)
• Testing laboratories and inspectors (monitoring and recordkeeping)
• Regulators and consultants concerned with safety, environmental impacts and adjacent-structure effects

Typical applications: preparing foundation ground for buildings, embankments, industrial sites, port infrastructure and mitigation of liquefaction-prone layers.

Related standards

• EN 1997‑1 / prEN 1997‑2 (Eurocode 7: ground investigation & geotechnical design)
• EN 1990 (Basis of structural design)
• EN 791, EN 996 (safety for drill rigs and piling equipment)

Keywords: EN 14731:2005, deep vibration, ground treatment, vibratory compaction, vibrated stone columns, depth vibrator, compaction probe, geotechnical works.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Execution of special geotechnical works - Ground treatment by deep vibrationLMRExécution de travaux géotechniques spéciaux - Amélioration des massifs de sol par vibrationAusfürung von besonderen geotechnischen Arbeiten (Spezialtiefbau) - Baugrundverbesserung durch Tiefenrüttelverfahren93.020Zemeljska dela. Izkopavanja. Gradnja temeljev. Dela pod zemljoEarthworks. Excavations. Foundation construction. Underground worksICS:SIST EN 14731:2006enTa slovenski standard je istoveten z:EN 14731:200501-februar-2006SIST EN 14731:2006SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14731September 2005ICS 93.020 English VersionExecution of special geotechnical works - Ground treatment bydeep vibrationExécution de travaux géotechniques spéciaux -Amélioration des massifs de sol par vibrationAusfürung von besonderen geotechnischen Arbeiten(Spezialtiefbau) - Baugrundverbesserung durchTiefenrüttelverfahrenThis European Standard was approved by CEN on 8 August 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2005 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14731:2005: E

Deep vibratory compaction.18 Annex B (informative)
Installation of vibrated stone columns.20 B.1 General.20 B.2 Dry top-feed process.20 B.3 Wet process.21 B.4 Dry bottom-feed process.22 Bibliography.24

1) Commonly termed vibro stone columns.
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