ASTM_C_1006_-_07_2013.pdf

Designation:C100607(Reapproved 2013)Standard Test Method forSplitting Tensile Strength of Masonry Units1This standard is issued under the fixed designation C1006;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the split-ting tensile strength of masonry units.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing Machines3.Significance and Use3.1 Masonry units alone and within assemblages commonlyfail in a tensile mode when loaded in compression to failure.These tensile stresses result from differences in modulus ofelasticity and Poissons ratio between the masonry unit andmortar.Additionally,the dissimilarity in behavior of the groutwithin cores of masonry units under load leads to tensilestresses in the units and results in a splitting failure.3.2 This test method produces a line load along the bedsurface of the masonry unit.The compressive load applied tothe unit,imposed by means of bearing rods,results in a tensilestress distributed over the height of the unit for the split lengthof the unit.This test method can be conducted with the rodoriented either in the longitudinal direction or in the transversedirection of the bed face.The splitting tensile strength iscalculated by the equation given in 7.1.3.3 The test value provides an indicator of masonry-unitsplitting tensile strength.Additionally,the presence of defectssuch as visible voids or impurities in masonry units may berevealed.4.Apparatus4.1 Bearing Rods Matched,paired steel bearing rods withdiameters within18to112of the specimen height,of a lengthgreater than the length of the intended test area,and ofstraightness within 0.5%of the specimen length shall beprovided for each unit.Bearing rods that meet the straightnessrequirement can be reused.4.2 Supplemental Bearing Bar or PlateIf the diameter orlargest dimension of the upper bearing face or lower bearingblock is less than the length of the specimen to be tested,asupplementary bearing bar or plate shall be used.The contactsurfaces of the bar or plate shall be machined to within 0.05%of planeness as measured on any line of contact of the bearingarea.The bearing bar or plate shall have a width of at least 2in.(51 mm),and a thickness not less than the distance from theedge of the spherical or rectangular bearing block to the end ofthe specimen.The bar or plate shall be used in such a mannerthat the load will be uniformly applied over the entire intendedsplit length of the specimen.4.3 Testing Machine:4.3.1 The testing machine shall conform to the requirementsof Practices E4,and may be of any type of sufficient capacitythat will provide the rate of loading prescribed in 6.3.4.3.2 The upper,hardened metal bearing face shall bespherically seated and attached at the center of the upper headof the machine.The center of the sphere shall lie at the centerof the surface of the plate in contact with the specimen.Thebearing plate shall be closely held in its spherical seat but shallbe free to turn in any direction;its perimeter at the ball faceshall have at least14in.(6.4 mm)clearance from the head ofthe machine to allow for specimens whose test surfaces are notexactly parallel.The diameter of the bearing surface shall be atleast 5 in.(127 mm).The bearing block surfaces that willcontact the bearing bar or plate shall not depart from planesurfaces by more than 0.05%.5.Sampling5.1 SelectionFor the purpose of this test,full-size ma-sonry units shall be selected at random by the purchaser or by1This test method is under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and is the direct responsibility of SubcommitteeC15.04 on Research.Current edition approved June 1,2013.Published June 2013.Originallyapproved in 1984.Last previous edition approved in 2007 as C1006 07.DOI:10.1520/C1006-07R13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United