运作方式，逐步说明
贯穿平台的 4 个步骤 - 每一步做什么，以及为什么重要。
Open the model
BIM 查看器Open the coordinated model and confirm elements are grouped the way the job is built - by zone, level and pour - so they can be tied to activities cleanly.
原因: A model organised by design discipline does not match how the site is sequenced. Grouping it the way the work happens is what makes a 4D link meaningful rather than cosmetic.
Link elements to activities
4D 进度计划Map each element or group to the schedule activity that builds it, so every part of the model knows when it goes up and comes down.
原因: The link is what turns a static model and a flat programme into a moving picture. It also flushes out the elements nobody scheduled and the activities with nothing to build.
Play and review the sequence
4D 进度计划Play the sequence and watch the build order: check access stays open, cranes can reach, temporary works come and go in time, and nothing is built before what holds it up.
原因: Finding an out-of-sequence pour or a blocked access on screen costs an hour. Finding it on site costs a week and a standing crew. The 4D review is where that saving is made.
Track progress against it
进度Use the 4D view to mark what is built and compare it to the planned sequence, so progress is shown as coloured geometry the whole team can read at a glance.
原因: A planned-versus-built model tells a client more in one image than a page of percentages. It makes slippage impossible to hide and easy to talk about honestly.