title: Measurement of concrete strength using the emission intensity ratio between Ca(II) 396.8 nm and Ca(I) 422.6 nm in a Nd:YAG laser-induced plasma.
abstract: An experiment to investigate the potential of a laser-induced plasma method for determining concrete compressive strength was conducted by focusing a Nd:YAG laser on concrete samples with different degrees of compressive strength. This technique was developed in light of the role of the shock wave in the generation of a laser-induced plasma. It was found that the speed of the shock front depends on the hardness of the sample. It was also found that a positive relationship exists between the speed of the shock front and the ionization rate of the ablated atoms. Hence, the ratio of the intensity between the Ca(II) 396.8 nm and Ca(I) 422.6 nm emission lines detected from the laser-induced plasma can be used to examine the hardness of the material. In fact, it was observed that the ratio changes with respect to the change in the concrete compressive strength. The findings also show that the ratio increases with time after the cement is mixed with water.
authors.affiliation: Kajima Technical Research Institute, Kajima Corporation, Tokyo 182-0036, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Tsuyuki
authors.forename: Satoru
authors.initials: S
authors.lastname: Miura
authors.forename: Nasrullah
authors.initials: N
authors.lastname: Idris
authors.forename: Koo Hendrik
authors.initials: KH
authors.lastname: Kurniawan
authors.forename: Tjung Jie
authors.initials: TJ
authors.lastname: Lie
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Kagawa
mesh_terms: D002118:Calcium / Q000032:analysis*; D019245:Compressive Strength; D003252:Construction Materials / Q000032:analysis*; D005740:Gases / Q000032:analysis*; D006358:Hot Temperature; D007834:Lasers; D008422:Materials Testing / Q000379:methods*; D010783:Photometry / Q000379:methods*; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D005740:Gases; D002118:Calcium