Before any model can be constructed or reconstructed, we need to know what actually our model is. Data gathering will provide us information about the structures built up, its properties, sections, foundations, environmental conditions and so on so forth. I usually spend 2 or 3 days doing data gathering at client’s office to get all the information I needed to construct my model. However, it really depends on how good data management is in your client’s office. You have a good data management you might end up 45 minutes for data gathering session but if you are not a lucky person, you can end up 1 week doing data gathering but still lacking the information.  What type of data that we are looking at? To simplify thing, here are the list of what I usually look at during my data gathering session (** refers to mandatory information):

1-      SACS structural input files** (usually denoted by SACINP.INP files. Very useful if you want to start modeling right away. First thing that I look during data gathering. You also can ask your client to prepare and give it to you to save your time constructing model from scratch.)

2-      Report on previous analysis

a.       Static in-place analysis **

b.      Spectral fatigue analysis

c.       Underwater inspection report, maintenance report

d.      Piling record (if available, this is sometimes hard to get!!)

e.      Construction report (also hard to find for old structure)

f.        Structural design report**

g.       Weight control report

3-      Foundations

a.       Soil investigations report**

b.      End bearing diagram/table**

c.       Shear strength diagram/table**

d.       Effective unit weight diagram/table**

4-      Environmental condition

a.       Previous and latest metocean criteria for 100 years load conditions **

5-      Structural drawings

a.       Show orientation and dimension of the structure**

b.      Details on piles design, pile to jacket connections, grouted or non-grouted**

c.       Conductors and risers

d.      Properties and sections**

Even though we can still model the structure using SACS input files only, it is not recommended to carry out modeling if most of the information is not on your table. The structure can be very different from its installation time to 20 years after that. Therefore, you need to make sure that all the information is ready before start the modeling. If not, ask your client to prepare it for you (and cut their cost on data gathering hours, they will be more than glad to do it for you).