50 
Post - ante C.d.M. 
Grid step 
I m 
2 m 
Interpolator 
ID. \ KR. ; TR. 
I.D. 
KR. \ TR. 
VOLUME 
Trapezium method 
lm 3 ] 
-623726 j -466398 j -470274 
-624276 
-466577 j -470555 
Simpson 
[m 3 l 
-623653 j -466365 j -470233 
-624192 
-466345 j -470255 
Simpson 3/8 
Im 3 J 
-623712 : -466398 i -470288 
-624435 
-466795 -470802 
Relative differences 
% 
0.01 j 0.01 j 0.01 
0.04 
0.10 j 0.12 
CUT VOLUME (negative) 
[m 3 ] 
1066680: 797773 j 804809 
1065040 
797171 : 804063 
FILL VOLUME (positive) 
[m 3 l 
442951 j 331375 j 334535 
440762 
330593 j 333508 
Variance • 2 
0.04 i 3.61 ; 62.41 
Weighted Av. CUT VOLUME 
[m 3 ] 
1063569 
Weighted Av. FILL VOLUME 
¡m 3 ] 
441660 
Post - ante Apr-98 
Grid step 
1 m 
2m 
Interpolator 
I.D. 
KR. 
TR. 
I.D. 
KR. 
TR. 
VOLUME 
Trapezium method 
[m 3 l 
-809716 
-703446 
-675914 
-809685 
-703482 
-675875 
Simpson 
lm 3 ] 
-809621 
-703328 
-675823 
-809367 
-703015 
-675423 
Simpson 3/8 
[m 3 ] 
-809772 
-703513 
-675959 
-809330 
-703398 
-675843 
Relative differences 
% 
0.02 
0.03 
0.02 
0.04 
0.07 
0.07 
CUT VOLUME (negative) 
lm 3 ] 
943420 
807071 
790516 
940980 
806232 
789423 
FILL VOLUME (positive) 
[m 3 l 
133704 
103625 
114602 
131295 
102750 
113548 
Variance • 2 
3.24 
40.96 
57.76 
Weighted Av. CUT VOLUME 
lm 3 ] 
926364 
Weighted Av. FILL VOLUME 
lm 3 ] 
130664 
subseque 
This mel 
the existi 
Therefor 
DEMs d 
finally to 
Referem 
Baiocchi 
S., Tun 
topografi 
ambienta 
Barbarei] 
di reti. B' 
Bitelli, C 
modello 
l’integrai 
Informati 
Carrara, 
technique 
contour 1 
Science, 
Carrara,. 
Analisi c 
modelli 
Telerilev; 
Crippa, 
determini 
delle alt 
Fotogram 
Crippa, f 
con splin 
Bolzano, 
Ebner, H. 
terreno: i 
Boll. SIE 
Table 6 - Volumes estimation 
7. CONCLUSIVE REMARKS 
The surveys on the ground can be performed with various 
techniques and instrumentation that allow to survey in 
contained times inaccessible zones or hardly practicable. 
The GPS allows to connect directly not inter-visible 
stations making more easy the job of country. 
If it is possible to know the shape of the ground after the 
event, that before the event depends exclusively on pre 
existing information. 
In order to digitize the cartography we prefer to perform 
the rasterization and the following vectorization of it; the 
algorithms semiautomatics give results the more efficient 
and reliable. If however the existing cartography is not 
careful and up-dated, the results are not reliable, 
obviously. 
The conclusion must be that it is very important to 
routinize the up-dating of the existing numerical 
cartography in order to estimate the handled ground. 
Otherwise it could be almost impossible to make reliable 
and accurate post-event analyses. 
The method used to produce DEM may heavily influence 
in the volumes evaluation while the thickness of the grid 
step does not influence at all. 
An alternative methodology in order to estimate the 
volumes might be the photogrammetric plotting of 
Ebner, E 
sviluppi e 
Fotiou, . 
variance 
and simili 
Hoffmani 
1993. GP 
Leick, A. 
Sons Inc. 
Lee, J., 1! 
topograph