Refer to clause 5.1.1 above.
Refer to the PSD for additional sample requirement if any.
5.4.2 Mock-ups
Subsequent to acceptance of the contractor’s detail design and prior to production, fabricate and build at locations as directed, a full size visual mock up for the SO to review.
Undertake any modifications throughout the stone cladding identified from the mock-up by the SO in order to meet the performance requirements and design intent.
Refer to the PSD for additional mock-up requirement if any.
5.5 Tests
5.5.1 Stone Testing 5.5.1.1 General
a. Submit method statements to the SO for review, describing how it is proposed to test the Works.
b. Test the Works and achieve results that verify to the SO that the performance requirements have been met.
5.5.1.2 Mechanical and Physical Properties of Stone
Submit to the SO test data for the proposed stone demonstrating compliance with the mechanical and physical properties as set out in clause 3.1. The test data shall be no more than 18 months old and from a laboratory accredited to carry out these tests.
5.5.1.3 Sampling
When the quarry has been selected and before any stone is processed for the cladding:
a. Take samples of each stone type from blocks representative of three widely spaced numbered locations in the intended extraction zone at the respective quarry (if all of the blocks for the project have already been delivered to the production facility then sampling may take place from these blocks rather than the quarry).
b. Arrange for the samples to be tested by the Testing Authority accredited to carry out the required tests and previously agreed with the SO. Submit the results to the SO.
c. If the results do not confirm the information previously submitted prior to
procurement or any modifications agreed at the time of Contract award, identify other extraction zones and continue sampling and testing until stones are found which comply with the agreed properties.
Retain all test specimens after testing to allow further inspection if required.
5.5.1.4 Acceptance
Reject all the stones represented by samples which fail to meet the requirements of mechanical and physical properties prior to procurement.
Remove the rejected blocks and slabs from the factory and place them in a separate disposal area.
5.5.2 Stone Approval Testing of Granite
From each of three number blocks (selected as part of the Sampling stage above), perform the following tests.
a. Density and Water Absorption. ASTM C97. From each block take three number specimens (nine in total).
b. Flexural Strength. ASTM C880. From each block take twenty number specimens (sixty in total). Ten specimens shall cut perpendicular to the rift in the stone and ten parallel to the rift. These shall be designated sets A and B. Test five
specimens from set A and five from B in the saturated condition and test the remaining ten specimens (again 5 from A and 5 from B) in the dry condition.
c. Compressive Strength ASTM C170. From each block take five number specimens (fifteen in total).
5.5.2.1 Acceptance
For each location calculate an average value for each group of tested samples. Use the result of all samples tested within each group in determining the average value, except if any specimen gives a value of 20% or more below/above the average.
Report any results 20% or more below/above the average to the SO and obtain authorisation of acceptability.
5.5.3 Tests for Fixings in Stone Prior to Processing 5.5.3.1 Samples for Testing
Provide 20 samples for testing unless otherwise directed.
The samples used to carry out the tests shall be taken from blocks taken from at least three separate parts of the quarry currently being worked. One or two samples shall be taken from an area as close as possible to that part of the quarry from which the stone for the project will be cut.
The same blocks shall be used to provide specimens for the stone property tests described elsewhere in this Contract Document, so that a relationship between the stone properties and the fixing tests can be established. The bedding plane or rift shall be marked on the specimens by the quarry.
The test specimens shall be not less than 300 mm x 300 mm by the minimum design thickness proposed by the Sub-contractor and shall be conditioned in accordance with the requirements of the most recent edition of ASTM C99. Larger specimens may be required if the failure cone in the stone is likely to be affected by the testing equipment.
The Independent Testing Authority shall keep all test specimens after testing to allow further inspections if necessary.
5.5.3.2 Pull-out Tests for Stud Fixings
a. 20 nos. pull out tests to destruction with the proposed stud fixings inserted into the appropriate thickness of stone parallel to the bedding plane or rift and with the stone wet and 20 nos. with the stone dry.
b. 20 nos. pull out tests to destruction with the proposed stud fixings inserted into the appropriate thickness of stone at right angles to the bedding plane or rift and with the stone wet and 20 nos. with the stone dry.
Calculate the mean and standard deviation of the failure loads for each set of 20 results.
Calculate the characteristic pull out value for each set as the mean pull out value of each set minus 1.83 times the standard deviation. The characteristic pull out value to be used for design shall be the lowest characteristic value calculated.
Submit results to the SO.
5.5.3.3 Shear Tests on Wind Tie Pins in Stone Edges
a. 20 nos. load tests to destruction with the proposed pin fixing inserted into the edge of the appropriate thickness of stone, with the bedding plane or rift parallel to the pin and with the stone wet, and 20 nos. with the stone dry.
b. 20 nos. load tests to destruction with the proposed pin fixing inserted into the edge of the appropriate thickness of stone, with the bedding plane or rift at right angles to the pin and with the stone wet, and 20 nos. with the stone dry.
Calculate the mean and standard deviation of the failure loads for each set of 20 results.
Calculate the characteristic breaking value for each set as the mean breaking value of each set minus 1.83 times the standard deviation. The characteristic breaking strength to be used for the pin fixing shall be the lowest characteristic value calculated.
Submit results to the SO.
5.5.3.4 Shear Tests on Horizontal Bottom Bracket Slots
a. 20 nos. load tests to destruction with the proposed horizontal kerf bracket design in the bottom edge of the appropriate thickness of stone, with the bedding plane or rift parallel to the kerf slot cut in the stone, and with the stone wet, and 20 nos.
with the stone dry.
b. 20 nos. load tests to destruction with the proposed horizontal kerf bracket design in the bottom edge of the appropriate thickness of stone, with the bedding plane or rift at right angles to the kerf slot cut in the stone, and with the stone wet, and 20 nos. with the stone dry.
Calculate the mean and standard deviation of the failure loads for each set of 20 results.
Calculate the characteristic breaking strength of each set as the mean strength of each set minus 1.83 times its standard deviation. The characteristic value to be used for design shall be the lowest value calculated.
Submit results to the SO.
5.5.4 Production Control Testing 5.5.4.1 General
Closely monitor the quality of the stone during production. Arrange for the Independent Testing Authority to carry out the following programme of physical testing.
Carry out the following production control tests.
Block Number Flexural Strength Density and Water Absorption Blocks 1 to 20 From every 5th Block. Six
specimens, 3 from each
orientation shall be tested in the dry condition.
From every 5th block 3 specimens shall be tested
Blocks 21 to 50
As above but from every 10th block.
As above but from every 10th block.
Blocks 50+ As above but from every 20th block.
As above but from every 20th block.
Should any significant variation occur in the results of the tests obtained during production then the testing regime shall revert back to that for blocks 1 to 20.
5.5.5 Visual Inspection Carry out a visual inspection:
a. After gang sawing and prior to further processing.
b. After initial processing and cutting to size.
c. After edge labours and surface finishing.
Submit a record with substantiating photographs to the SO.
5.5.6 Dye Testing (Granites Only)
Dye test the two outermost usable slabs from the first five blocks to be produced using a fluorescent dye to determine the presence of potentially harmful cracks and micro cracks.
The necessity for an additional dye testing shall be determined following the results of these tests.
Any stone exhibiting cracks deemed to be potentially harmful by the SO shall be excluded from production.
5.5.7 Impact Testing
Carry out impact tests where required as indicated in the PSD.
5.5.8 Weathertightness and Load Testing of Stone Cladding Specimen Provide stone for weathertightness and load testing where identified by the SO.
5.5.9 Site Load Testing of Fixings 5.5.9.1 General
Demonstrate by test that fixings are adequate
Laboratory tests shall be carried out generally in accordance with BS 5080 Parts 1 and 2.
Site testing shall be carried out in accordance with the methods described in Construction Fixing Association Guidance Note “Procedure for site testing construction fixings”
Retain all test specimens.
5.5.9.2 Site Inspections of Fixings As the Works proceed check that:
a. The fixings as detailed on the installation drawings have been installed.
b. Every cladding fixing to structure is the right size and is in the right place and has been correctly tightened using a calibrated torque wrench.
c. Fixings do not restrain any intended movement and generate locked-up stresses.
5.5.9.3 Quality Control Testing of Bolts Embedded in Concrete
As the Works are installed, carry out 10 nos. tests at each floor level on any embedded bolts:
Load to a minimum load of 1.1 times the design load acting on the bolt.
Record and submit displacement measurements.