construction projects

hello svec2008!

construction scheduling is not GUESSING, it's PLANNING.

some books for construction estimates gives us the capability (low, average & high) of one (1) man or unit of equipment to do a certain job. but you can not say that the duration to do this job is by dividing the quantity (unit) by the capability (unit per hour). it depends on how many person or equipment will do the job.

if an activity will be done by manpower & equipment, always have a sufficient or more numbers of manpower inorder to maximize the use of equipment. rate of manpower is cheaper than the rental rate of equipment.

for construction scheduling, it is be better to use the capability of one crew with the tools & equipment.

example:

CREW COMPONENT

• 1-leadman
• 2-riggers
• 4-fitters
• 2-welders
• 4-helpers

TOOLS/EQUIPMENT

• 1-20T crane
• 2-welding machine
• 2-cutting outfit
• 1-miscellaneous tools

but then, you have to determine how many groups/crew you need depends on the work area, availability of materials, availability of tools & equipment, target to complete as the subsequent activity has a fixed date of start, etc...

if you are on the contractor side, it is be better to use the data or work capabilities of your previous projects.

always coordinate with site engineers and keep records of your previous projects.

a project is 80% planning and 20% implementation.

Thank you very much for your opinion, I have been involved into planning for a long time now , and what you are saying is quite true there is no guess into planning , and this is what I meant by "time standard" .

Although as a first estimate for a project planning I think we need the work standards of the industry and take it as a reference for our planning then we compare it to our output . this is what I meant in my question, if somebody knows a reference "time standard" for different activities in construction .I have been involved most of the time into manufacturing activities , and we can find plenty of such data available . For the construction I could not find such data , maybe because it is related to each one's activity.

thank you fo your intervention it is very interesting .

Now, dear sir, comparing a manufacturing which is a controlled environments with a construction implementation is wrong. Firstly you have to appreciate the site conditions, constraint due to environmental forces, available tools and special tools etc. It is a different world. To estimate time line for earthworks would require you to know your machinery involve, dump site, stagging works required etc..

That is why a planner for civil engineering project should be a well exposed civil engineer who understand the mechanism of project. Otherwise your CPM would go to ICU. jsut my penny tought.