Power's Model

Question 1

Porosity can be classified into which 3 classes?

Answer 1

Trapped or entrained air vods
Gel pores
Capillary pores

Question 2

How many grams of water combine with 1g of cement?

Answer 2

0.23

Question 3

What is the specific volume of
unhydrated cement
gel solids
gel, including gel voids

Answer 3

Unhydrated cement: 0.318 mL/g
Gel solids: 0.411 mL/g
Gel, including gel voids: 0.567 mL/g

Question 4

100 grams of cement is how many mL?

Answer 4

0.318 mL/g x 100 g = 31.8 mL

Question 5

How to calculate the volume of gel solid after hydration?

Answer 5

After hydration, cement and water mix to create gels.
So for gel SOLID, get the combined weight of the possible reaction and convert it to mL using gel solid specific volume (rmb only 0.23 g of water reacts with 1 g of cement).

Question 6

How to calculate the volume of gel pores after hydration?

Answer 6

Gel pores = Gel - gel solid
To calculate gel, similar to gel solid:
Cement and water mix to create gels.
So for GEL, get the combined weight of the possible reaction and convert it to mL using gel specific volume (rmb only 0.23 g of water reacts with 1 g of cement).

Question 7

How to calculate the volume of capillary pores after hydration?

Answer 7

Assuming water is more than adequate:
Volume of water + cement = vol. of capillary pores + vol of gel
Vol. of capillary pores = Vol. of water + cement - vol. of gel
Vol. of capillary pores = w + 0.318c - 0.567(c + 0.23c)
Vol. of capillary pores = w - 0.38c

Question 8

What is the capillary porosity?

Answer 8

It’s equal to w/c - 0.38 mL/g of original cement
also = vol. of capillary pores/c