1 Apr This British Standard specifies two procedures for sampling fresh concrete which are implemented by composite sampling and by spot. 1 Jan Buy BS EN TESTING FRESH CONCRETE – PART 1: SAMPLING from SAI Global. Buy UNI EN Testing Fresh Concrete – Part 1: Sampling from SAI Global.
|Published (Last):||9 December 2011|
|PDF File Size:||17.89 Mb|
|ePub File Size:||9.29 Mb|
|Price:||Free* [*Free Regsitration Required]|
Apparatus Mold Mold use for slump test of fresh concrete Dimension in mm Metallic, Frustum of a cone Alternative materials are allowed if requirements are met comparability tests Tamping Rod Round, straight steel rod, length mm and diameter 16mm Tamping end rounded to a hemispherical tip Measuring Device Ruler Marked in increments of 112350-1 mm or smaller Length of at least mm In addition, a scoop is needed.
Sn This practice specifies methods for making and curing test specimens for strength tests.
Sampling of Freshly Mixed Concrete at the Field (BS EN ) – QA/QC Construction
The vertical distance between the height of the mould and the highest point is measured and recorded as the slump in mm. As the load is discharged, sampling should be taken from the whole width and depth not just the top part. It depends upon the project specifications on particular project area of jurisdiction.
Significance and Use The slump test was originally developed to provide a technique to monitor the consistency of unhardened concrete. Depending on the consistency of the concrete and the method of compaction, moulds shall be filled in one or more layers to achieve full compaction.
Fill the mold in three layers of approximately equal height. If a falling away or shearing occurs, disregard test and make a new test using another portion of the sample. Materials handling, Test specimens, Sampling methods, Concretes, Samples, Cement and concrete technology.
dn Minimum size of sample x 1. The first school of thought is rather straightforward: I have a presentation subsequent week, and I am on the look for such info. Full compaction is achieved using mechanical vibration, when there no further appearance of large air bubbles on the surface of the concrete and the surface becomes relatively smooth with a glazed appearance, without excessive segregation.
BS EN – Testing fresh concrete. Sampling – BSI British Standards
Complete the temperature measurement within 5 min except for concrete containing the coarse aggregate of a nominal maximum size greater than 75 mm which may require up 12350–1 20 min for the transfer of heat from the aggregate to the mortar. Extended delays in placing can lead to a significant loss of consistency with time making it impossible to place with satisfactory compaction.
What is the time limit before placing of fresh concrete? Subject the concrete to a sufficient number of strokes per layer, typically Sampling Concrete It is sn to measure the temperature in: Worldwide Standards We can source any standard from anywhere in the world.
1350-1 some big projects, imagine the time consumed to perform the composite sampling when there is a lot of concrete truck mixers in queue at the checkpoint area. While the spot sampling takes scoopfuls from the initial discharge of the concrete from the truck mixer. Avoid over-vibration, which may cause loss of entrained air. BS EN specifies two procedures for sampling fresh concrete, by composite sampling and by spot sampling.
After this, the design mix specific to the particular type of structure recommends the discharge time limit waived against what is stated in the specifications. These limits are sufficient for normal UK temperatures. Find Similar Items This product falls into the following categories.
BS EN 12350-1:2009
Your basket is empty. Foreword Scope Normative references Terms and definitions Apparatus Em Report of sampling See more standards on testing concrete. Frequency shall be at least vibrations per minute The diameter of the internal vibrator not exceeding one-quarter of the smallest dimension of the test specimen Vibrating table with a minimum frequency of 40 Hz 2 cycles per minute Compacting rod or bar Preparation and filling of the moulds Before filling the mould, cover the inner enn of the mould with a thin film non-reactive release material to prevent the concrete from adhering to the mould.
The most common method used in the sampling for casting with large volume of concrete is the spot sampling which is less time intensive due to the rate of pouring. Ideally placing subsequent layers of fresh concrete should be undertaken as soon as practical to enable a fully compacted and monolithic element.
It may be used to verify conformance to a specified requirement for the temperature of concrete. If the tamping operation of the top layer results in subsidence of the concrete below the top edge of the mould, add more concrete to keep an excess above the top of the mould at all times.
Compaction of the concrete The concrete shall be compacted immediately after placing in the moulds in such a way as to produce full compaction of the concrete with 12305-1 excessive segregation nor laitance.
Scoopfuls are taken from four different parts of the load to form the standard sample. Concrete cubes at the site Marking The test specimens shall be marked clearly and indelibly, without damaging the specimen using a cub tag that contains the information related to the specimen Casting date, ticket number, specimen ID, location of sampling….