Geometric and mechanical properties of hollow concrete blocks manufactured in the area of Tuxtla Gutiérrez (Chiapas, Mex.)
This paper presents the results of a series of tests for geometric and mechanical characterization of concrete block (from 8 local factories) and cement mortar used in masonry in the region of Tuxtla Gutierrez. The laboratory tests were performed according to standards and protocols of Mexican organisms. The results of the analyzed samples show that the height of the blocks is very variable and differs from the standard values while the other dimensions and wall thicknesses comply with the regulations. The compressive strength of the mortar specimens is good (4 times higher than required). The total water absorption of the blocks is greater than the maximum allowed (12%) in half of cases tested, but the volumetric weight does not reach, in any case, the minimum one required (1700 kg/m³). The compression strength of individual pieces and block piles (manmade with type I mortar) is much lower than that required in the regulations (60 kg/cm² and 50 kg/cm² respectively). The quality and poor strength shown by the tests carried out warn of the need for regulation and local control of the block manufacturing process.
Keywords: concrete block, mechanical testing, compression resistance, masonry, regulation.