Research on NDT Technology in Inference of Steel Member Strength Based on Macro/Micro Model

Table 7

Coefficient estimates of yield strength model.

Yield strength model	Coefficient estimates	95% confidence interval of
		Lower limit	Upper limit
Constant	−314.302	−443.432	−185.173
HLD	1.526	1.212	1.840
	3.318	0.720	5.917
C percentage (%)	−174.066	−334.770	−13.363
Si percentage (%)	−2.324	−88.397	83.749
Mn percentage (%)	37.646	19.459	55.832
P percentage (%)	609.908	−244.132	1463.948
S percentage (%)	−217.509	−962.534	527.516