1.0.1 This standard is formulated with the view to unifying the method of inspecting normal concrete compressive strength with test hammer and guaranteeing the inspection precision.
1.0.2 This standard is applicable to the inspection of the normal concrete compressive strength of engineering structure (hereafter referred to as concrete compressive strength simply).
The inspection may be carried out according to this standard when it is required to inspect the concrete compressive strength of structure, and the results may be adopted as the gist for dealing with the concrete quality problems.
This standard is not applicable to inspection of the concrete structure or element with evident difference between surface layer and internal quality or those with defects inside.
1.0.3 The workers engaged in engineering inspection with test hammer shall accept the vocational training authorized by the executive department, and shall also possess relevant qualification certificate.
1.0.4 Besides the provisions stipulated in this standard, those in the current relevant mandatory standards of the nation shall be complied with for inspection and estimation of the concrete compressive strength by rebound method.
1 General provision 1
2 Terms and symbols 1
2.1 Terms 1
2.2 Symbols 1
3 Test hammer 2
3.1 Technical requirements 2
3.2 Verification 2
3.3 Maintenance 3
4 Detection technology 3
4.1 General provision 3
4.2 Rebound value measurement 5
4.3 Measuring of the carbonation depth 5
5 Rebound value calculations 6
6 Strength curve 7
6.1 General provisions 7
6.2 Unified strength curve 7
6.3 The provincial and special strength curve 8
7 Calculation of the concrete strength 8
Annex A Conversion table for concrete compressive strength of test area 10
Annex B Corrected value of the conversion value of pump concrete compressive strength of test area 18
Annex C The corrected value of rebound value inspected in non-standard state 19
Annex D Corrected value of the rebound value of different pouring surface 20
Annex E Drawing method of special strength curve 22
Annex F Report on concrete compressive strength inspection by rebound method 24
Explanation of Wording 25
