Crack Paths 2012

With the consideration of the heating condition of glass in case of fire, a kind of

glazing situation was designed to investigate the thermal stress distribution and crack

propagation as shown in Fig. 1. There are four parts for the glass to be considered in

temperature rising, E1, E2, B1 and B2, respectively. E1 denote the glass exposeing to

the fire directly and E1 is shaded by frame at the same side. B1 means the glass back

side and B2 is shaded by frame at the same side. At the central part (E1) of the glass, the

temperature rising rapidly, and the other parts are rising slowly. The exact temperature

rising plots are shown in Fig. 2, respectively.

Crack

path

Enlarged tip

mesh

Fig. 2 Glass temperature rising history with time at four parts shown in Fig. 1.

Fig. 3. Meshsubdivision for the

simulation of crack growth.

Table 1. Glass properties [8] and other parameters used in simulation

Properties

Symbol Value

Units

Thermal expansion co-efficient

8.0×10 – 6

K–1

Pa

Modulus of elasticity(Young Modulus) E

7.0×1010

Poisson’s ratio

0.25

--

Density

2520

kg/m3

Ultimate tensile strength

4.0×107

Pa

ut

Pa

Ultimate compressive strength

4.0108

uc

Glass size

--

0.006×0.6×0.6 m3

Shaded edge width

0.02

d

m

Meshnumber

2×36×36

--

--

Time step

t

1

s

A glass is an inorganic non metallic material that does not have a crystalline structure.

Typical glasses range from the soda-lime silicate glass for soda bottles to the extremely

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