inclination of holes can generally be achieved in the overburden drilling
Down the hole hammer is also capable of maintaining a better control on the
However, the hammer may get clogged when the drill cuttings form slush in form
d ia g o n a l b ra c e to
g u s s e t p la te
E re c tio n b o lt,
if re q u ire d
R e q u ire d c o n n e c tio n le n g th
b e tw e e n g u s s e t p la te a n d
b ra c in g m e m b e r
D ia g o n a l b r a c in g
G u s s e t p la te lo c a te d
o n b
What methods are commonly used to provide finished surfaces, when required?
Some of the cutting methods in the previous question result in surfaces that are
finished without further treatment.
When this is not the case, the following methods are commonly
Special surface-condition requirements must be specified in the contract
documents. Material purchased to meet
the requirements of ASTM A6/A6M is usually subject to acceptance or rejection
based upon visual inspection
both at the rolling mill and at the t
purchased from a warehouse, the
selection of available lengths may be further limited. Additionally, the method of
shipment may also limit the
Material Identification and Traceability
What is required for the identifi
To what ASTM Specifications are hollow structural sections (HSS) ordered?
ASTM A500 grade B (although ASTM A500 grade C is increasingly very
common) and A847 are appropriate
when specifying square, rectangular, and round HSS. These specifications cove
evaluate the deviation and
whether it would be detrimental to the end use of the product.
In some cases, repair will be required and can usually be made so that the member
will meet all performance
criteria. Corrective measures to meet the requirements of
will bypass the brace.
Gusset Plates. Gusset plates may be a variety of sizes and shapes. It will be
dictated by the force in the diagonal brace and the thickness of the gusset plate. If
the gusset plate is hidden within a wall, the size and shape of
bearing . shall have the bearing surfaces of individually fabricated pieces
prepared by milling, sawing, or other
suitable means." The 2000 AISC Code of Standard Practice Section 6.2.2
Commentary states that "Most cutting
processes, including friction saw
PAGE 65 MATERIALS
Case A Case B Case C Case D
Rati Rati Ratio
be achieved either by the application of water (usually from sprinklers or
hoses, or occasionally by panding on the top of the lift) or by prevention of loss of
(by application of some membrane to the surface). A second requirement for go
Most systems have non-linear behavior
LTI Systems are often a good (local) approximation
Feedback can be used to linearize systems
Beware of finite actuator ranges (clipping)
Transfer Function (1)
For Transfer Functions, the effect of a mo
drainage curtain provided in the foundation apart from checking of design
for its stability.
Seismicity of the Area and Dynamic Characteristic of the Structure
Surveillance of seismic environment of the project site needs special attention in
three pegs of tilt plate and senses change in tilt of tilt plate. The portable indicator
the degree of rotation.
Measurement of Stress
Direct measurement of stress developed inside the mass of concrete or masonry
in watching the structural beh
4.6.11 Structural design of special components
Although maximum value of concrete in gravity dam construction goes into mass
concreting, reinforcements are required at some places for resisting tensile stresses.
these two components are quit
Version 2 CE IIT, Kharagpur
to the surrounding area will immediately reveal any distress conditions developing
dam. Measurement of displacement is thus one of the most important factors to be
studied while observing the structural behaviour
provided all round the openings, and special care taken where two openings meet,
at the junction of the foundation gallery and an inspection adit. Is 12966(part 2)
gives guidelines for both evaluating the stresses and design of reinforcements. I
delicate than strain meters and hence, it is a common practice to measure the strain
and to calculate from it the developed stress.
Measurement of Pore Pressure
Since large concrete and masonry dams are provided with internal formed drains
located near th
opening or of closing of surface cracks at any location.
Measurement of vertical or horizontal displacement of foundation provides
for taking preventive measures for inclination, distortion etc. of structures. The
using chutes or even a belt conveyor. It is recommended that concrete shall have to
placed in position within 30 minutes of its removal from the mixer.
Concrete placing, consolidation and curing
For laying concrete over the rock foundations, it
When no return of drilling or washing water occurs, the holes should be washed for
reasonable period based on site experience. This is generally for 20 minutes. If an
abrupt loss of drill water occurs during drilling and similarly when a strong flow of
c . fric?on coeffficient
k . spring constant
u . applied force
m p + c p + k p = u
Continous and Discrete Models
Examples: Spring Mass, Cruise Control, DC Motor, .
The following measurements are optional and may be undertaken where warranted
special circumstances of project. These would be beneficial for high dams, for
structures of unusual design, for structures where unusual or doubt
reading will result because of OPTICAL PARALLAX. (Parallax was covered in
3, Introduction to Circuit Protection, Control, and Measurement.)
Always choose an instrument suitable for the measurement desired.
Select the highest range first an
of coil movement now depends only on the resistances of R1 and R2.
The addition of R1 and R2 into the meter circuit raises the total series resistance
and decreases the
current. This decreases the amount of pointer deflection. The pointer comes to rest
the resistance more
accurately because scale readings are more easily interpreted at or near midpoint.
An ordinary ohmmeter cannot be used for measuring multimillion ohm values of
resistances, such as
those in conductor insulation. To test
because resistor R 100 has only 1/10 the resistance of resistor R 10.
Q-23. The R 100 resistance selection on an ohmmeter has what amount of
resistance compared to the
R 10 selection?
The circuit arrangement in view A of figure 3-14 allows the same amount
In testing for grounds, you may use a megger or an ohmmeter. Measuring the
resistance to ground
from points in a circuit determines if the point is grounded. Referring again to
figure 3-20, you can see
one possible means of testing a cable for grounds. If