ARCC 2202 Lecture Notes - Lecture 8: Shear And Moment Diagram, Fly Ash, Vapor Barrier
16 Dec 2016
School
Department
Course
Professor
Lecture Eight
Concrete
Recycled Material
Fly ash, also known as "pulverized fuel ash" in the United Kingdom, is one of the residues
generated by coal combustion, and is composed of the fine particles that are driven out of the
boiler with the flue gases. Can be used to displace cement.
Recycled concrete: Crushed concrete can be used to replace aggregate
Moment diagrams of a steel beam
CONCRETE FUNDAMENTALS:
•basic ratio: 1 cement, 2 sand, 3 gravel
•water - cement ratio: kept below 60% of weight of cement
•too much water will create a defect
•slump test is used for testing of ratio
•aggregate must be small enough to pass through small rebar
*about 28 days for concrete to cure fully
•!burlap commonly used to keep the cement wet
•fly ash also known as “pulverized fuel ash”
•first time used?
•the efficiency tower, has a RC foundation for the massive structure
find more resources at oneclass.com
find more resources at oneclass.com
•Concerete beam reinforcement
•must be at the top and bottom (tension and compressions parts)
•bending moment diagram••
•given branding moment diagram••
Installing a proper concrete slab
a) Install slab edge to supporting stakes
b) Slab section ready to pour with vapour barrier, welded wire fabric reinforcing, and edge forms
in place
c) Asphalt impregnated fibre board forms a control joint
d) Striking off the surface of the slab
e) Bull float for preliminary smoothing
f) Hand floating brings cement paste to the surface
g) Floating can be done by machine
h) Steel troweling after floating produces a dense hard smooth surface
i) Finished section of concrete slab ready for curing
j) One method for damp curing a slab: cover it with polyethylene sheeting
One Way Slabs
Depths are typically 100 - 250mm (4-10”). The most economical beam is one whose depth is 2
or 3 times the breadth.
However, one way slabs are often supported by beams that are several times as broad as they
are deep, called slab bands.
Advantages: the width of the band reduces the span of the slab resulting in a reduced thickness,
the reduced depth allows for a reduction in floor to floor height resulting in economies from
reductions in cladding, partitions, vertical ductwork etc.
Two Way Slabs
Two-way flat slab are generally more economical where the columns can be spaced in bays that
are nearly square.
find more resources at oneclass.com
find more resources at oneclass.com
