Graficos & Abacos
11
-
Upload
ignacio-quispe-mayta -
Category
Documents
-
view
36 -
download
0
description
ABACOS PARA CARATERIZACION GEOMECANICA
Transcript of Graficos & Abacos
Christian Obregon
Rectangle
1
2
89o
85o
70o
60o
50o
40o
30o
20o
10o
5o
1o
89o
85o
80o
70o
60o
50o
40o
30o
20o
10o
5o
1o
30'
10'
90o
70o
60o
50o
40o
30o
20o
10o
5o
1o
True dip
Apparent dip
Angle between strike and apparent dip
Fig. 1.7 Alignment diagram (nomogram) for use in solving apparent-dip problems. Place a straight edge on the twoknown values to determine the unknown value. As shown on the diagram, if the true dip of a plane is 438 and the anglebetween the strike and the apparent dip direction is 358, then the apparent dip is 288. After Palmer (1918).
ROWLAND / Structural Analysis and Synthesis 01-rolland-001 Final Proof page 10 26.9.2006 4:59pm
10 -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Attitudes of Lines and Planes ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
3
164W
edgefailure
Dip of plane B
B chart—dip difference 20°
Rat
io B
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
00 20 40 60 80 100 120 140 160 180
360 340 320 300 280Difference in dip direction—degrees
260 240 220 200
Dip of plane A
A chart—dip difference 20°
Rat
io A
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
00 20 40 60 80 100 120 140 160 180
360 340 320 300 280Difference in dip direction—degrees
260 240 220 200
9080
605040
30
304050
20
3040
5060
70 70
Figure 7.10 Wedge stability charts for friction only: A and B charts for a dip difference of 20◦.
4
Shear strength of rock discontinuities
9
0 10 50 60
Schmidt hardness - Type L hammer
Ham
mer
orie
ntat
ion
50 100
150
250
Average dispersion of strengthfor most rocks - MPa
20
22
24
26
28
3032
Uni
t w
eigh
t of
roc
k - k
N/m
3
400350300
250
200
150
10090807060
50
40
30
20
10
Uni
axia
l com
pres
sive
stre
ngth
- M
Pa
20 30 40
0 10 20 30 40 50 60
0 10 20 30 40 50 60
0 10 20 30 40 50 60
0 10 20 30 40 50 60
200
+ + + + +|| | | |
Figure 7: Estimate of joint wall compressive strength from Schmidt hardness.
5
Shear strength of rock discontinuities
8
0.1 0.2 0.3 0.5 1 2 3 4 5 10
Length of profile - m
2016121086543
2
1
0.5
Join
t Rou
ghne
ss C
oeffi
cien
t (JR
C)400
300
200
100
504030
20
10
1
0.1
0.2
0.30.40.5
2
345
Am
plitu
de o
f asp
eriti
es -
mm
Length of profile - m
Asperity amplitude - mm
Straight edge
Figure 6: Alternative method for estimating JRC from measurements of surfaceroughness amplitude from a straight edge (Barton 1982).
6
VALORES CONTINUOS DE RMR1,2,3 (Bieniawski, 1989)
7
8
INTACT ROCK & ROCK MASS EQUATIONS
Christian Obregon Mitma 9
105
α
Figura 3.19: Diagramas de la sección y transversal de un ensayo de inclinación o “tilt-test” con testigos para
obtener el ángulo de fricción básico según la propuesta de Stimpson (1981).
Figura 3.20: Imagen de la realización en laboratorio de un ensayo de inclinación o “tilt-test” con testigos para obtener el ángulo de fricción básico según la propuesta de Stimpson (1981).
A partir de la configuración geométrica del ensayo, Stimpson demostró que el ángulo de
fricción básico de la roca de los testigos se podía calcular como:
2arctan ·tan
3bφ α =
(3.24)
Este ensayo resulta sencillo, barato y fácil de repetir y de gran utilidad para aplicar el modelo
Barton-Bandis de estimación de las propiedades resistentes de la discontinuidades rugosas sin
relleno, que son las que más comúnmente se encuentran en gran parte de los macizos rocosos
a partir de cierta profundidad, por lo que se suele utilizar muy a menudo.
10
