1. Egg Protection Device (EPD) - Structural Competition
Used materials
Mixture procedure
To effect the mixture, we use a small “dough mixer” (Binder mixer).
Portland Cement
Type: CP V – ARI
Company: Cement Cauê – Camargo Corrêa
Specific mass of the cement: 3,12 kgf/cm3
Blaine fineness: 4118 cm2/g
Used amount: 852 kg/m3
Water
Company: LABTEC
pH: 6,80 ±0,15
Used amount: 259 kg/m3
Small Aggregate
Company: IPT (Institute of technological research)
Category: Sand
Nature: Quartz Sand
Specific mass of the aggregate: 2,69 kgf/cm3
Used amount: 658 kg/m3
Grain sized distribution
Great aggregate
Used amount: 198 kg/m3
Silica Fume
Company: Elkem Materials South America
Type: Material that improves the properties of the concrete. It contains of 85% 98% of amorphous silicon dioxide. The particles have spherical form and are microscopical.
Specific mass of the silica fume: 2,20 kgf/cm3
Used amount: 213 kg/m3
In the photo above the types of stirrups are presented.
Cure procedure
The mixing sequence was the following:
70% of the water and total amount of superplasticizers
To add the cement total amount carefully
Separately to join the silica fume, small aggregate and the great aggregate in a container.
To add total amount in a container to the mixture, carefully.
And 30% of the water
Mixing for 4 minutes
After to take off the EPD of inside of the acrylic box, we initiate the cure process.
We below follow the steps shown in the graph.
To obtain the temperature of 82ºC, we use a drum cut to the way, where he was filled a part with water and under we had a small stove.
System of molding
We made a screwed acrylic box, where the steel structure was incased inside. After placing the concrete through the feet of the EPD we closed it. Later 24-hour, we disassembled the acrylic box and the EPD was ready for the cure.
Final Result
Steel structure
To compose the structure of the EPD, we choose a steel that has good resistance the traction.
The wires had been confectioned in order to get a good performance when if to apply the impact.
The stirrups had been placed the 45 degrees, to prevent to the maximum the shear force.
Gratefulness
It would like to be thankful first for the health, and all my family. To always be thankful also my sponsor (CAUÊ CEMENTS - CAMARGO CORRÊA) giving support at the difficult moments.
Water-reducing admixture (Superplasticizers)
Type: Sika Viscocrete 20 HE 2003
Company: Sika
Specific mass of the cement: 1,08 kgf/cm3
Solid percentage: 35%
Efficiency results: Fluid concrete, High initial and final axial compressive strength
pH: 6,60 ±0,10
Used amount: 28 l/m3
Steel structure
Type: Steel Wire
Company: Belgo Mineira – (Bekaert)
Classification: High carbon text
Diameter: 1,58 mm
Resistance the traction: 2450 MPa
Faculty Advisor
_____________________
Prof. Marco Antonio Carnio
Student: Fábio Albino de Souza – Engeneering Civil