14. OBJECTIVES
At the end of the lesson, students should be
able to:
1. define the form, scaffolding and staging,
2. discuss the concept of wood board and plywood
forms, and
3. draw a formwork.
15. ACTIVITY
Locate the given words, running in
one of ten possible directions
horizontally, vertically, or diagonally.
16.
17.
18. Concrete mixture is generally semi-fluid
material that produces shape of anything to
which is poured. Thus, Construction form is
used to produce the desire size, shape, and
form for concrete. Concrete weights about
2,200 kg. to 2,400 kilograms per cubic meter,
hence, it requires forms that are substantially
strong and rigid enough to sustain the weight
and horizontal pressure of fresh concrete.
19. Forms must be watertight,
simple, and economically
designed to be removed and
reassembled easily without
damage to themselves or to the
concrete.
20. The selection of forms to be used depends on
the following considerations:
1. The cost materials.
2. The construction and assembling cost.
3. The number of times it could be used.
4. Strength and resistance to pressure and tear and
wear.
21. Cost of Materials is the primary consideration in
all kinds of construction work. And cost of forms
is not an exception to this primary objective.
Indeed, most of the form should be viewed in
totality of its service rather than the unit cost of
the materials alone. For instance, a certain form
material cost much higher than the other but it
could be used for multiple times as compared
with that of a cheaper one that could be utilized
only one or twice.
22. Construction and assembling cost - refers to the
ease of assembling the forms. In general, cost
under this consideration refers to the kind of
materials, the manner of assembling and the cost
of labor. Comparatively, laminated plywood is
much easier to assemble and to work on than the
other type of materials, and this is the reason the
use of plywood as form gained wide acceptance
in almost all construction work.
23. Strength and resistance to pressure and tear
and wear refers to the quality and strength of
the form to resist the weight and horizontal
pressure of fresh concrete. The thickness of the
form, the size and spacing of the frame depends
upon the nature of the structure to be supported
classified as small medium or massive
structure.
25. As forms, Plywood has the following
advantages:
1. Plywood is generally economical both in cost and labor.
2. Plywood has plain, smooth, and even surface with uniform
thickness.
3. When jointed, plywood is easily fitted eliminating extra cost
for dressing finished concrete.
4. Plywood is lightweight material, handy and fast to work on.
5. Plywood forms produces smooth finished concrete that
sometimes needs a little or no plastering at all.
26. Ordinary Plywood - This type of plywood is
not resistant to moisture or water
saturation. If used as forms, its service could
be limited to one or two times.
Marine Plywood - is a waterproof material
suitable for all types of work that needs a
laminated board. As concrete form, it could
be used in multiple times if properly handled
in assembling and dismantling.
28. Two types of framing adopted for plywood forms
1. The longitudinal rib type
2. The Perpendicular rib type
29. Form for Concrete beam
Forms for concrete beam consist of one
bottom form having a width equals the
width of the beam plus 4 inches and two
side forms having a width equals the
depth of the beam.
32. Forms can be secured with:
1. Nails
2. Cleats and braces
3. Tie wire
4. Bolts
5. Clamps
33. Wall Forms
Wall forms are usually mounted in pair opposite at a
distance equal to the thickness of the wall secured
rigidly strong to resist the lateral pressure of a fresh
concrete. Wall forms must be guarded against
bulging, the most common failure of form. The use of
bolts or tie wire has been proven to be effective and
economical means of securing wall forms.
34.
35. Wall forms are classified into the following types:
1. Continuous form
2. Full unit form
3. Later unit form
a. Continuous
b. Sectional
36. The advantages and the disadvantages of the full unit and
the layer unit form are:
1. The Layer Unit Form is considered economical as far as
the material is concerned. The same form is being used on
different sections that involve labor for the removal and
assembling of the same form. The disadvantage, therefore, is
the delay and labor cost.
2. The Full Unit Form has a disadvantage of cost by buying
the entire materials for the full unit of the work. On the other
hand, it has the advantage of one labor assembling cost, one
setting of mixing and pouring and the shortest time involved.
37. Greasing of Forms
The purpose of greasing the form is to make
the wood waterproof. Thus, preventing
absorption of water in the concrete that causes
swelling and warping of the forms. Greasing
also prevent adherence of concrete to the pores
of the wood and likewise, prevent rust on
metal forms.
38. APPLICATION
Let’s see if you can now apply what
you have learned. This time you are
going to draw your own formwork
design.
39. QUIZ!!!
1. It is generally semi-fluid material that produces
shape of anything to which is poured.
a. Concrete mixture
b. Cement
c. Construction form
d. Mixture
40. 2. __________ is used to produce the desire size, shape, and form for concrete.
a. Mixture
b. Cement
c. Construction form
d. Concrete mixture
3. _______________ is the primary consideration in all kinds of construction work.
And cost of forms is not an exception to this primary objective.
a. Construction form
b. Concrete mixture
c. Cement
d. Cost of materials
41. 4. This refers to the ease of assembling the forms. In general, cost under this
consideration refers to the kind of materials, the manner of assembling and the cost
of labor.
a. Labor
b. Cost
c. Cost of labor
d. Construction and assembling cost
5. This type of plywood is not resistant to moisture or water saturation. If used as
forms, its service could be limited to one or two times.
a. Marine plywood
b. Ordinary plywood
c. Plyboard
d. Hardwood
42. 6. It is a waterproof material suitable for all types of work that needs a laminated
board. As concrete form, it could be used in multiple times if properly handled in
assembling and dismantling.
a. Marine plywood
b. Ordinary plywood
c. Wood
d. Hardwood
7___________ are usually mounted in pair opposite at a distance equal to the
thickness of the wall secured rigidly strong to resist the lateral pressure of a fresh
concrete.
a. Wall forms
b. Beams
c. Post
d. Formwork
43. Test II Essay type
1. Why is it important to secure our
formworks? (3points)
