Earthwork Computations
Earthwork Computations
(OP)
My kind greetings,
Right now, my Companay is working on 82km road project in Nasarawa, Nasarawa State, Nigeria; it is well known fact that earthwork quantities covers more than 35% of the Total Contract Sun on road projects.
Several CAD systems (including CIVILCAD,AUTOCAD etc.) has been empolyed by most Draft engineers on site to calculate volumes of earthworks done. None, seems to predict the 'actual' quantity or volume of earthworks carried out for defined section or chainages (stations).
These inaccuraries and errornous 'Computer Outputs' made the project consultants to advice the Employer to pay the Contractor on a linear basis; ie Lenght*Breath*Depth. Whereas the thickness of 'fill' or 'cut' for formations is clearly stated in the Project drawings; and was not followed when preparing Interiem Certificates.
The general implications/cost overruns now boils down to the Contractor who achived over 0.8 - 1m plus depth on earthwork and paid less for more work done on site.
Please, can anyone advice the Contractor and if possible CAD systems that is generally acceptable to the Industry in calculating volumes of earthworks.
Kind regards, Pls.
Right now, my Companay is working on 82km road project in Nasarawa, Nasarawa State, Nigeria; it is well known fact that earthwork quantities covers more than 35% of the Total Contract Sun on road projects.
Several CAD systems (including CIVILCAD,AUTOCAD etc.) has been empolyed by most Draft engineers on site to calculate volumes of earthworks done. None, seems to predict the 'actual' quantity or volume of earthworks carried out for defined section or chainages (stations).
These inaccuraries and errornous 'Computer Outputs' made the project consultants to advice the Employer to pay the Contractor on a linear basis; ie Lenght*Breath*Depth. Whereas the thickness of 'fill' or 'cut' for formations is clearly stated in the Project drawings; and was not followed when preparing Interiem Certificates.
The general implications/cost overruns now boils down to the Contractor who achived over 0.8 - 1m plus depth on earthwork and paid less for more work done on site.
Please, can anyone advice the Contractor and if possible CAD systems that is generally acceptable to the Industry in calculating volumes of earthworks.
Kind regards, Pls.
nurhforward, Gitto International.





RE: Earthwork Computations
RE: Earthwork Computations
Remember GIGO Garbage in garbage out. If data is wrong so do output. Also consider creating close cross sections when abrupt changes do occur.
PIZER Sales: 1-800-222-5332 1-206-285-6100
FAX: 206-634-0624
E-MAIL: sales@pizer.com
PIZER Incorporated
4422 Meridian Avenue North
Seattle, WA 98103
U.S.A.
RE: Earthwork Computations
I do agree with davilara01 that the accuracy of the calculations is purely dependant on the quality of the models.
cheerypicker
RE: Earthwork Computations
What are assumptions for shrink/swell? Are they based upon pre-design geotech work? How detailed was the geotech work? How far between testing? How much do the ground conditions vary over the 84km? Does the calculation input take all of this into account?
RE: Earthwork Computations
RE: Earthwork Computations
RE: Earthwork Computations
RE: Earthwork Computations
RE: Earthwork Computations
RE: Earthwork Computations
RE: Earthwork Computations
I found that doing pit calculation to be the most accurate with survey before and after, show exactly what the contractor used to build the project.
RE: Earthwork Computations
RE: Earthwork Computations
Terramodel with the "Roads" package is excellent at this sort of work.
RE: Earthwork Computations