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Reuse Stainless Steel Bolts
QUESTION:if you're sure your education is so thorough, consider a typical highway
job:
- What type of equipment is the contractor going to use to do the
excavation ?
- How large a crew will he have?
- Which side of the road will he choose to install sidewalks on first?
- Will he install the drainage first and then the gas under it, or put the
gas in first and risk hitting it with the excavator?
- What type of concrete curb will he install ? (the spec says precast,
but gives him the option to do cast in place)....etc
If you can answer all those questions during design, I'd like to hear your
rationale and see how close to the truth you are when construction season
rolls around.
ANSWER: Methinks you have not provided enough information on at least two of the
items (and as the engineer you should have provided the info), but since my
specialty is construction management (and contractor bidding), I'll do the
best I can.
- If excavation is clay or sand, likely a hydraulic excavator or gradall,
depending on volume. Use queuing theory (engineering comes in handy!) to
determine optimum number of trucks to use for haul and disposal of spoil
depending on haul distance, also need to determine in design if project is
cut or fill (must be known by designer to do a good job), which will
determine ultimate pricing of excavation, embankment and grading, try to
design to balance fill (equal cut and fill) to minimize costs, determine
from soil borings if dewatering is required, etc........(not really enough
info here from you).
- Will depend on size of project, but can be estimated from reliable
sources such as Means estimating guide for any task you can think of. Hell,
they even give costs per unit (SF, CY, ton, etc......) for engineers that
don't want to think in terms of crews or don't understand the function of
persons on a project site.
- Put gas in first. One ALWAYS works from lowest layer in a road section
and work up, if it is possible. Sometimes contractor cannot control utility
companies, and engineer should understand this and provide thorough design
to minimize utility conflicts. This method of construction is always true
when the contractor controls all the operations on a project (the preferred
method, by the way), and still governs contractor's schedule even when
Contractor doesn't control all activities (you'd know this if you ever had
to deal with a contractor claim for utility conflicts due to deficient
design).
- Contractor will build pre-cast if you tell him to, unless he can do it
cheaper with cast-in-place. If it is less expensive to cast-in-place, he
will provide a VECP (hope you know what those initials mean) to you, the
engineer, to do C.I.P. concrete, and will usually share cost savings, but
you should know which is cheaper and easier going in, or should ask before
bidding. Pre-cast is almost always less expensive given optimum conditions
(faster, therefore cheaper). Also, I have never seen pre-cast concrete curb
on any project I've been involved in. Pre-cast temporary barrier wall, yes,
but pre-cast curb would be very difficult to install on grade to maintain
proper invert.
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