Concrete Cutting Cutter Groton MA Mass Massachusetts
Welcome
to AffordableConcreteCutting.Com
“We
Specialize in Cutting Doorways and Windows in Concrete Foundations”
Are You in Groton Massachusetts? Do You
Need Concrete Cutting?
We Are Your Local
Concrete Cutter
Call 800-799-9151
We Service Groton MA
and all surrounding Cities & Towns
“No Travel Charges – Ever! Guaranteed!”
Concrete
Cutting Groton MA Concrete Cutting
Groton Massachusetts
Concrete
Cutter Groton MA Concrete Cutter
Groton Massachusetts
Concrete
Coring Groton MA Concrete Coring Groton
Massachusetts
Core
Drilling Groton MA Core
Drilling Groton Massachusetts
Concrete
Sawing Groton MA Concrete Sawing
Concrete
Cutting MA Concrete
Sawing Groton Mass
Concrete
Cutting Groton Mass Concrete Cutting
Groton Massachusetts
Concrete
Cutter Groton Mass Concrete Coring
Mass
Core
Driller Groton MA Core
Drilling Groton Mass
Groton
Massachusetts Concrete Cutting and Core Drilling
This
method is cumbersome, however, and is not used. As has already been pointed out
the moment of resistance equals the total tension times the lever arm of the
resisting couple; or BM=MR= T.a=f.A5.a using the
notation already familiar. The arm, a, varies so little for varying tension
steel areas that it may be assumed constant without serious error. With this assumption
it becomes possible to lay down the principle that the area of steel required
varies directly with the bending moment and the same curve by proper choice of
scale mar serve both as moment curve and area-required curve. Usually practical
considerations as to commercial size of bars result in the maximum area
furnished being larger than that required. It is common to neglect this
difference and compute bar lengths as though the maximum area furnished equaled
that required. This reinforced concrete beam (Fig. 24) carries a uniform load.
What are the minimum possible values of the dimensions a and
b. The bending moment curve for this loading is a parabola with maximum
ordinate at the center and the area-required curve accordingly is the same. The
parabola of Fig. 24b is drawn with the center ordinate representing 6 sq. in.
One bar may be bent up when 5 sq. in. only are required; so a = 9'4 = 3.7 ft. Similarly a + b = 9v' = 6.4 ft.
Shearing Stresses in
Homogeneous Concrete Beams
A
brief review of the shearing stresses in homogeneous beams is desirable in
order that a clear picture may be obtained of the web stresses in beams of all
kinds. For rigorous demonstration of these matters the reader should consult
the standard treatises on the strength of materials are equal. Knowledge of the
variation of horizontal shear intensity, therefore, gives also that of vertical
shear. In Fig. 25b is shown a portion of a rectangular beam lying between any
two sections, AA' and BB'. The variation of normal tension intensity at each
section is indicated by the partial stress diagrams, the abscissas on AA' being
shown larger than those on BB' on the assumption that the moment at AA', is the
larger. Considering the stability of the small piece of beam cdBA, the pull on the cA face is
larger than that on the dB face and the only force available to balance the
difference is the horizontal shear on the plane ed. A brief consideration of
the problem shows that the nearer the cd plane is to
the neutral plane ab, the larger is the difference
between the two tensions, and the larger the horizontal shear. Therefore the
horizontal shear, and accordingly also the vertical shear, increase in
intensity at a decreasing rate from zero at the extreme fiber to a maximum at
the neutral plane. For a rectangular section the law of this variation is a parabola
(Fig. 25a) with a maximum intensity of 317. The resultant intensity of stress
at any point away from the extreme fibers, as, for example, on the vertical
faces of the elementary prisms 1 and 2, Fig. 25a, must be inclined in
direction, acting somewhat as shown. Referring again to the elementary prism
shown, the shearing forces there shown may be resolved into components along
the diagonals, and these components may be combined to give inclined tensile
and compressive forces acting at 45 degrees (Fig. 25d) with an
intensity (v) equal to that of the shear. This illustrates the case when
the prism lies at the neutral plane where there is no direct stress. When it
lies in the face of the beam there are no horizontal nor
vertical shearing stresses and the resultant tension is horizontal, being that
given by the usual formula for fiber stress. A more detailed study of the state
of stress at any point in this cross-section would show that passing through it
are two inclined planes, 90 degrees apart, on which there is no shear, the
resultant stress being compression on one and tension on the other, of
intensity greater than on any other plane through the point. These stresses are
called the principal stresses at the point. Midway between these planes are those
of maximum shear intensity. In the web of a plate girder the action of the
inclined tension is
easily resisted by the steel but the diagonal compression tends to cause
buckling and it is necessary to limit the minimum thickness of the web or to
provide suitably spaced stiffeners, or both. In a concrete beam, on the other
hand, the material easily resists the diagonal compression but is weak in
tension. The wooden beam resists both.
Are You in Groton Massachusetts? Do You
Need Concrete Cutting?
Call 800-799-9151
We Service Groton MA
and all surrounding Cities & Towns
Concrete
Cutting Groton MA Concrete Cutting
Groton Massachusetts
Concrete
Cutter Groton MA Concrete Cutter
Groton Massachusetts
Concrete
Coring Groton MA Concrete Coring
Groton Massachusetts
Core
Drilling Groton MA Core
Drilling Groton Massachusetts
Concrete
Sawing Groton MA Concrete Sawing
Concrete
Cutting MA Concrete
Sawing Groton Mass
Concrete
Cutting Groton Mass Concrete Cutting
Groton Massachusetts
Concrete
Cutter Groton Mass Concrete Coring
Mass
Core
Driller Groton MA Core
Drilling Groton Mass
Groton Massachusetts Concrete Cutting and Core Drilling