18.1.1 Direct calculations may be used to assess the scantlings of primary structure in spoil spaces and adjacent structure.
18.1.2 Direct calculations may be required to be submitted in respect of unusual structural arrangements.
18.2.1 Methods applied for direct calculations of scantlings will be given individual consideration dependent on the particular structural configuration, see also Pt 3, Ch 1, 3.1 Alternative arrangements and scantlings.