1. Doctoral Candidate, Structural Engineering and Mechanics Group, Dept. of Civil Engineering, Univ. of Cape Town, Rondebosch 7701, Cape Town, South Africa. ORCID: .
2. Professor and Head, Structural Engineering and Mechanics Group, Dept. of Civil Engineering, Univ. of Cape Town, Rondebosch 7701, Cape Town, South Africa (corresponding author).