to the top bar 206 and bottom bar 207 at a first end to form a first pair of lateral slots 211 and 212 for receiving 2 u2033 u00d7 4 u2033 beams vertical bars 213 214 and 215 are welded to middle portion of the top bar 206 and bottom bar 207 to form a pair of center slots 216 and 217 for receiving 2 u2033 u00d7 4 u2033 beams vertical bars 218 219 and 220 are welded to the second end of top bar 206 and bottom bar 207 to form another pair of lateral slots 221 and 222 for receiving 2 u2033 u00d7 4 u2033 beams a horizontal bar 223 is welded to vertical bars 210 and 213 to form a pair of central slots 224 and 225 respectively for receiving 2 u2033 u00d7 12 u2033 planks another horizontal bar 226 is welded to vertical bars 215 and 218 to form another pair of central slots 227 and 228 respectively for receiving 2 u2033 u00d7 12 u2033 planks a first leg bar 203 is welded at its upper end to the first end of the top section 201 and welded at a lower end to a diagonal brace 243 a second leg bar 204 is welded at an upper end to the second end of the top section 201 and welded at a lower end to a diagonal brace 244 an elongate base bar 202 is welded at a first end to a lower portion of first leg bar 203 a predetermined distance from diagonal brace 243 base bar 202 is welded at a second end to a lower portion of second leg bar 204 a predetermined distance from.