A platform for research: civil engineering, architecture and urbanism
Impact response of lightweight mortars containing expanded perlite
Abstract This paper describes the mechanical response of lightweight mortars subjected to impact loading in flexure. Expanded perlite aggregate with a bulk density of 64kg/m3 was used at between 0 and 8 times by volume of Portland cement to yield a range of mortars with density between 1000 and 2000kg/m3. Some specimens were reinforced with a polypropylene microfibre at 0.1% volume fraction and the dynamic fracture toughness was evaluated by means of an instrumented drop-weight impact system. Companion tests were carried out in compression under quasi-static loading to standardise the mixes. The compressive strength and elastic modulus scale as the cube of the relative density, defined as the ratio of the density of the mortar to that of Portland cement paste. Whereas the flexural strength and fracture toughness were both linearly proportional to the relative density of the mortar under quasi-static loading, there was an increase in their sensitivity to relative density at higher loading rates. Contrary to what is seen in regular concrete, fibre reinforcement led to an increase in the stress-rate sensitivity of flexural strength in lightweight mortars. For the same impact velocity, the stress-rates experienced by a specimen was strongly influenced by its density. While the stress-rate sensitivity of flexural strength dropped with a decrease in the mix density, that of the fracture toughness was consistently higher for the lighter mixes.
Impact response of lightweight mortars containing expanded perlite
Abstract This paper describes the mechanical response of lightweight mortars subjected to impact loading in flexure. Expanded perlite aggregate with a bulk density of 64kg/m3 was used at between 0 and 8 times by volume of Portland cement to yield a range of mortars with density between 1000 and 2000kg/m3. Some specimens were reinforced with a polypropylene microfibre at 0.1% volume fraction and the dynamic fracture toughness was evaluated by means of an instrumented drop-weight impact system. Companion tests were carried out in compression under quasi-static loading to standardise the mixes. The compressive strength and elastic modulus scale as the cube of the relative density, defined as the ratio of the density of the mortar to that of Portland cement paste. Whereas the flexural strength and fracture toughness were both linearly proportional to the relative density of the mortar under quasi-static loading, there was an increase in their sensitivity to relative density at higher loading rates. Contrary to what is seen in regular concrete, fibre reinforcement led to an increase in the stress-rate sensitivity of flexural strength in lightweight mortars. For the same impact velocity, the stress-rates experienced by a specimen was strongly influenced by its density. While the stress-rate sensitivity of flexural strength dropped with a decrease in the mix density, that of the fracture toughness was consistently higher for the lighter mixes.
Impact response of lightweight mortars containing expanded perlite
Kramar, Derek (author) / Bindiganavile, Vivek (author)
Cement and Concrete Composites ; 37 ; 205-214
2012-10-10
10 pages
Article (Journal)
Electronic Resource
English
Impact response of lightweight mortars containing expanded perlite
Online Contents | 2013
|Lightweight Mortars Based on Expanded Perlite
British Library Conference Proceedings | 2018
|Mechanical properties and size effects in lightweight mortars containing expanded perlite aggregate
Online Contents | 2010
|Mechanical properties and size effects in lightweight mortars containing expanded perlite aggregate
Online Contents | 2011
|Mechanical properties and size effects in lightweight mortars containing expanded perlite aggregate
British Library Online Contents | 2011
|