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7.6.3 Elements of production and construction control

P(1) The production and construction controls include:

— initial tests and checking procedures,

— test and checking in the course of construction,

— final tests and checks.

(2) Different verification systems may be appropriate for:

— a continuous production; the aim of this system is to achieve a uniform quality of the products in the long term;

— a single product; the aim is mainly to comply with the basic requirements of the project.

(3) For a single product, it may be appropriate to concentrate on precautionary measures, in particular on initial tests and on checks during construction.

7.6.4 Initial tests

P(1) Where necessary, initial tests shall be made before the start of the construction process in order to check that the intended structure can be constructed satisfactorily using the specified materials, equipment and construction methods.

(2) The quality and compatibility of the building materials and constituent materials for concrete, mortar, etc. should be shown to be adequate, either by reference to previous experience or by means of prior tests. Only approved materials should be used.

(3) For the initial test on concrete, see sections 3—(25) and 11 in ENV 206.

7.6.5 Checks during construction

7.6.5.1 General requirements

P(1) The dimensions, the properties of the materials and their suitability, the components built into the structure and the equipment used shall be subjected to a permanent system of verification during construction.

P(2) When materials and components are received at the site, their compliance with the terms of the original order shall be checked.

P(3) Important findings shall be filed in written reports, (for example in the site journal) which shall be available to all the parties concerned.

(4) Depending on the degree of reliability required, additional special control measures may be agreed.

(5) For the production control of concrete, section 11 in ENV 206 applies.

(6) For all other structural materials, reference should be made to relevant technical documents (eg CEN-standards).

(7) The site journal should contain the information on concrete as defined in section 10.3 or section 11.2.1 of ENV 206 as appropriate and the following information as a minimum:

— time needed for individual operations (e.g. placing of concrete, removal of formwork).

— the delivery of construction materials and components,

— the results of test and measurements,

— observations and measurements on the position of the reinforcement and tendons,

— description of extraordinary occurrences.

7.6.5.2 Compliance controls at delivery to the site

(1) For the delivery note for ready-mixed concrete, section 10.3.2 of ENV 206 applies.

(2) For precast units, the delivery note should certify that the precast components were manufactured, marked and treated in accordance with the order.

(3) In addition to (2) above, the delivery note should contain the following information:

— date of manufacture and delivery of the unit,

— identification markings and, if required, the reference number of each component in accordance with the requirements of the customer's order,

— information on the material, e.g. grade of concrete, grade of steel for reinforced concrete, concrete cover, etc.

(4) The delivery tickets for reinforcing steel should include information on the following items:

— steel in long length or in reels or in "steelworks" condition,

— bars or welded mesh fabrics,

— pre-assembled reinforcement

(5) For all reinforcement, it is necessary to be sure of the origin and the identity of the steel delivered. This can be ensured by:

— an indication, on documents of certification, of the steel being delivered.

(6) For prestressing steel and prestressing devices, Section 6.3.4 of this Code applies. 7.6.5.3 Controls prior to concreting and during prestressing

(1) For the controls prior to concreting, Section 11.2.3 of ENV 206 applies.

(2) Before being placed in position, the tendons should be inspected for any damage that might have occurred since arrival on site or at the factory.

(3) Before tensioning it is advisable to check that the prestressing operation can be carried out correctly. Checks should be made that the requirements of 6.3.4.5 are being met, at the time of transfer of the prestressing force.

(4) A prestressing record should be kept of the measurement made at each stage of stressing (pressure in the jacks, elongations, slippage at the anchorages, etc.).

(5) The time elapsed between prestressing and the completion of the protective measures for the steel (grouting) should be controlled and noted.

Before grouting, it should be ensured that the provisions of 6.3.4.6.3 and 6.3.4.6.4 are applied and checked.

(6) During grouting it is necessary to check the injection pressure, the free flow of the grout from the vents, to look for grout leaks, to check the quantity of injected grout as well as to take samples for checking viscosity and loss of water. Where necessary, the strength of the grout should be checked.

7.6.6 Conformity controls

P(1) Conformity control is understood to be the combination of actions and decisions to be taken in order to verify that all requirements, criteria and conditions laid down previously are met completely. This implies completing relevant documentation.

(2) For the conformity control of concrete, Section 11 in ENV 206 applies.

(3) The conformity control of other materials should be based on International Standards or, where they do not exist, on National Standards or Approval Documents.

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