The table below lists activities for constructing a bridge over an operational railway line, similar to the bridge described in Case 10.3. Activity No Activity Description Predecessors Duration (months) A 2 B 6 A 6 B Detailed site investigation and survey Detailed planning Detailed design Preparation of site Relocate services Re-align overhead track electrification D 4 E 3 CE F 4 G 1 D H 2 G 3 J K 2 L 2 F,G L 2 M 1 2. 3 Q R Access road and ramp construction Piling Construct foundations and abutments Construct temporary supports to support bridge deck during construction Fabrication planning of structural steel components Manufacture structural steel components (off-site) Transport structural steel components and erect on-site Erect pylons and fill with concrete Construct main span deck on pre-cast concrete beams Install stay-cables and lift the bridge deck off temporary supports Remove temporary supports Electrical system installation Roadway surfacing (paving) Finishing and ancillaries Commissioning - cut-over Formal hand-over & ceremony Project sign-off Administrative closure Project End J H, K, N, P Q R 3 S 1 T 1 S U 2 S V 2 TU V w 1 1 W Y 1 Z W Y, Z AA 0 (milestone) 1. Construct a network diagram for the project. 2. Do forward and backward pass calculations to indicate early and late start and finish times. 3. Indicate the critical path. 4. Indicate the total and free slack of each activity