Plate Load Test on Fill

[Jalthi]

We performed a plate load test on supposedly properly compacted (not verified yet) engineered fill material. The fill was approximately 3 feet thick and covered an area of 15 ft. by 15 ft. The load was applied on a 30 inch diameter plate (30 at bottom 18 on top) increased in the steps of 5 psi from 5 psi to 50 psi. The total settlement measured was 1-inch at 50 psi. The tangent slope of the settlement vs pressure curve is close to 50 psi/inch and yield an elastic modulus of 1000 psi. See formula below.

E = slope * PI/4 * D * (1-v^2)
where D = Diameter = 30 inch
v = Poisson's ratio = 0.4

However, the material can be classified as sandy gravel or gravelly sand. In any case, the typical elastic modulus is 10 times higher than what is obtained from the test.

Any suggestions as to why the results are not in the bracket are much appreciated.

Thanks in advance.

 

[fattdad]

Here's a link that may help:

http://www.ce.tuiasi.ro/~bipcons/Archive/141.pdf

f-d

¡papá gordo ain’t no madre flaca!

 

[Ron]

Sounds like the material was not properly compacted. Probably wrong moisture content at time of compaction (too dry).