1

COMBINED BLAST AND FRAGMENT LOADING EFFECTS ON REINFORCED

CONCRETE STRUCTURES

Yau Jia Ming Spencer

1, Kang Kok Wei

2

1Anglo Chinese Junior College, 25 Dover Close East Singapore 139745

2Defence Science and Technology Agency, 1 Depot Road, Singapore 109679

ABSTRACT

Concrete has been used since the Roman Empire and has been made stronger in modern

times with the addition of steel reinforcing bars (rebars), which form reinforced concrete

(RC). The cost effectiveness, reasonable strength and high malleability has contributed to its

popularity in the construction industry. This research study aims to understand the response

of RC slabs against combined blast and fragment loadings in the design of protective

structures. Since small countries such as Singapore suffer from land space constraint,

practical experiments are limited thus the need for computation software such as LS-DYNA,

which is used in this study. Through LS-DYNA, parameters such as arrangement of rebars

and boundary conditions, have been varied to study the response of RC against blast as well

as combined blast and fragment loadings. Findings include the decreasing relationship of the

damage extent of the RC slab to increments of rebars as well as the stark difference in the

response of the RC against combined blast and fragment loading compared to its response

against blast loading solely.

INTRODUCTION

Resilience of reinforced concrete (RC) structures to dynamic loadings has been well

researched in the protection of human or equipment within buildings. The loading effects

from conventional weapons include both blast and fragments. The latter is generated from the

breakup of metal casing around the explosives within. While blast and fragment loadings are

well documented individually, there are limited data on the combined blast and fragment

loading effects. The objective of this research is to analyse the physical response of an RC

slab to combined blast and fragments loadings.

Since small countries such as Singapore suffer from land constraints, practical experiments to

study the combined blast and fragment effects are limited thus the need for computation

software such as LS-DYNA. Apart from saving resources, numerical analysis using these

computational software develop trends or patterns without the need for numerous live testing.

However, such software and simulations run on equations that are built on data only found

through experiments. Hence, some live testing is still required.

This paper is divided into 2 sections: Blast Loading on RC Slabs and Combined Blast and

Fragments Loading on RC Slabs. Each section will discuss about their respective loading,

present the methods and discuss the results.

RESEARCH APPROACH

In the analysis of the RC slab subjected to various dynamic loadings, the software, LS-

DYNA, which originated from the Lawrence Livermore National Laboratory in 1976, is

used. This software is primarily used to numerically analyse structures which are subjected to

a variety of impact loading. For this research, we will be analysing the stress visually and z-

displacement graphically of the RC slab when it is loaded. An example of stress analysis can

2

be seen in Figure 1 [1]. Usually, the red regions will indicate high stress values and vice versa

for blue regions.

Figure 1: An example of visual stress analysis [1]

Packaged together with the LS-DYNA Solver is a software called LS-PrePost. This is a both

a PreProcessor as well as a PostProcessor. The former allows users to setup models prior to

the analysis while the latter enables users to analyse and visualise the output from LS-DYNA.

For this research study, the PreProcessor is used to create a slab model, which measures

3x1x0.2m and the following parameters are varied:

Boundary conditions,

Element Size

Arrangement and number of loading segments

Arrangement and number of rebars

Figure 2 Measurements of the RC slab model

Details of the parameters above will be described in subsequent sections. The rest of the

parameters such as the ones below can be created using LS-PrePost but, in this study, a

separate file is written using the computer program WordPad to specify these values into the

model:

charge mass,

stand-off distance, and

the type of loading (blast and combined blast and fragments for this research)

An example of the file is included in the Annex A.

After analysing the model using LS-DYNA, the PostProcessor allows the user to analysis the

damage and response of the RC slab loading visually and graphically. For the graphs, only

the first peak deflection is considered as the subsequent oscillations of the slab is deemed

unphysical. Given more time, this problem can be numerically resolved.

0.2m

1m

3

BLAST LOADING

This section describes the analysis of a RC slab subjected to blast loadings, which assumes

the use of bare Trinitrotoluene (TNT). The shape of the charge is assumed to be spherical and

it is detonated in the air. This is known as airblast. Variations of the quantity and arrangement

of rebars, boundary conditions, element size and scaled distances were studied in this

research. Fortunately, LS-DYNA can calculate the blast load data. Hence there is little need

for manual calculations. Grade 30 concrete and Grade 460 steel for the rebars in the model.

Quantity & Arrangement of rebars

In RC slabs, rebars are important as they contribute greatly to the tensile capacity of RC.

Concrete is highly resistant to compressive stresses but responds poorly to tensile stress.

Therefore, the quantity and arrangement of rebars can alter the capacity of RC slabs to blast

loading. For this study, 20x20x20mm solid elements are used to model concrete while the

rebars are modelled using 20mm long beam elements. An explosive charge weighing 10kg,

which is placed 2m above the top surface of the slab, is detonated in this case. Three models

are created in this study. The models in Figures 3(a) and 3(b) have two layers of rebars but

the number of rebars per layer is varied: 5 rebars per layer for Figure 3(a) and 10 rebars per

layer for Figure 3(b). The model in Figure 3(c) is similar to the one in Figure 3(a) but without

a layer of rebars near the top surface.

(a) (b) (c)

Figure 3 Models used to study the effects of varying the rebar quantity and

arrangement

By comparing images in Figures 4(a) and 4(b) and the curves in Figure 5 (Figure 4(a) having

10 rebars and Figure 4(b) having 20 rebars), there is a decrease in the overall midspan

vertical- or z-displacement of the slab and damage when the quantity of rebars increase. The

same can be said when the number of rebar layers increase in the case of Figures 4(a) and

4(c) (Figure 4(c) having 5 rebars). When the slabs are bent as shown in Figure 6, the top

surface of the slab is subjected to compression while the bottom of the slab is subjected to

tension. Since rebars have a higher tensile strength than concrete, the overall tensile strength

of the slab increases with increments in rebar content, which reduces the overall z-

displacement of the slab as well as the damage.

(a) (b) (c)

Figure 4 Damage of the soffit of the slabs with various rebar arrangements after loading

4

Figure 5 Midspan displacement histories of the slabs with various rebar arrangements

Boundary Conditions

Figures 6 Bending response of the RC slabs under blast loading

There are 2 main types of supports for RC structures: pinned and fixed. Pinned support

provides translational restraints but not rotational restraint at the ends whereas fixed support

provides both translational and rotational restraints. Two models were created to study the

effects of these boundary conditions. Figures 6(a) & 6(b) represent fixed and pinned supports

respectively. The entire surfaces of the model in Figure 6(a), which are darkened, are

restrained whereas, for the model in Figure 6(b), only an edge on the soffit of the slab has

been restrained. They are also illustrations of both boundary conditions and their appearances

in the models [2]. The other parameters remain unchanged and the models are similar to the

one in Figure 3(a).

(a) (b)

Figure 6 Models used to study the effects of varying the boundary conditions

The RC slab with fixed supports in Figure 7(a) suffered less damage than the slab with

pinned supports in Figure 7(b). The z-displacement is significantly greater for the slab with

5

pinned supports than the slab with fixed supports as seen in Figure 8. Pinned supports are

commonly seen in pre-cast concrete buildings such as the many HDB flats in Singapore. An

example of a structure with fixed supports is a bomb shelter as it is a single piece of structure

with no weak linkages. Since fixed supports offer more resistance to rotational movement

(moment) than Pinned supports, the slab with fixed supports will be more resilient to loading

forces and pressure exerted, resulting in less damage; as observed in Figures 7(a) and 7(b).

(a) (b)

Figure 7 Damage of the soffit damage of the slabs with (a) fixed and (b) pinned supports

after loading

Figure 8 Midspan displacement histories of the slabs with fixed and pinned supports

Element Size

In LS-PrePost, 2 meshes of the RC slab described in Figure 3(a) are formed but the number

of elements are varied as it was believed that this parameter has an effect on the RC slab

response to impact loading. The slab in Figure 9(a) consists of 1,000 solid elements of

300x100x20mm while the slab in Figure 9(b) comprises of 75,000 solid elements of

20x20x20 mm.

(a) (b)

Figures 9 Models used to study the effects of varying the element size

The slab made of small solid elements in Figure 10(a) has suffered significantly less damage

from the impact loading than the slab made of large elements in Figure 10(b). At stand-off

distances of 1m & 2m and charge mass of 10kg, there is almost no difference in the z-

displacement of the slab as seen in Figure 11. However, for the stand-off distance at 2.15m

and charge mass of 100kg, the slab in Figure 10(a) has a smaller z-displacement than the slab

in Figure 10(b) as seen in Figure 11; showing an increasing relationship of the z-displacement

and the stress as the quantity of elements increases. It could be due to the average impulse,

6

from the blast loading, per element being higher for the slab in Figure 10(a) than the slab in

Figure 10(b); tallying with the results.

(a) (b)

Figure 10 Damage of the soffit of the slabs with (a) small and (b) large elements after

loading

Figure 11 Midspan displacement histories of the slabs with various element sizes at

various stand-off distances and charge mass

Scaled Distance

Scaled distance is defined as the ratio R/C1/3

where R is the stand-off distance of the

explosive charge from the target and C the explosive charge mass. Most blast parameters can

be derived from scaled distance as shown in Figure 12. Two scaled distances are studied in

this section: 0.46m/kg1/3

and 0.92m/kg1/3

. The former is based on a 10kg explosive mass at

stand-off distance of 1m while the latter is based on the same explosive quantity at a stand-off

distance of 2m. For the former, another scenario of a 100kg explosive mass with a stand-off

distance of 2.15m is studied.

Figure 12 Derivation of various blast parameters based on scaled distance [3]

Figures 13(a), 13(b) and 13(c) shows the damage of the three scenario studied. As expected, a

higher scaled distance will lead to less damage by comparing Figures 13(a) and 13(b), in

which the charge weights are the same but the stand-off distances are 1m and 2m

7

respectively. It is also noted that although the scaled distances are the same for the slabs in

Figure 13(a) and 13(c), the use of a higher charge mass on the slab in Figure 13(c) resulted in

a larger amount of explosive materials reacted, producing more kinetic energy and thus a

very powerful shockwave. This will lead to more damage. The z-displacement histories of the

three scenarios are plotted in Figure 14 and the results relate well with the damage

comparisons in Figure 13. Thus, in addition to scaled distance, the individual components of

this expression i.e. the explosive charge mass and stand-off distances are also important.

(a) (b) (c)

Figure 13 Damage of the soffit of the slabs with various scaled distances of (a)

0.46m/kg1/3

(10kg@1m), (b) 0.92m/kg1/3

(10kg@2m) and (c) 0.46m/kg1/3

(100kg@2.15m)

Figure 14 Midspan displacement histories of the slabs with various scaled distances of

(a) 0.46m/kg1/3

(10kg@1m), (b) 0.92m/kg1/3

(10kg@2m) and (c) 0.46m/kg1/3

(100kg@2.15m)

COMBINED BLAST AND FRAGMENTS LOADING

The preceding section focuses on loading from a bare spherical charge but, under the loading

of an exploding weapon, there are fragments generated in addition to the blast. Hence it is

important to consider the combined blast and fragment loading of a cased charge when

building a RC structure designed against weapons. This section studies and discusses the

combined effects of blast and fragments by implementing an engineering methodology to

predict the loading. Though there are built in values for blast loading, the fragment loading

data has to be calculated separately and inserted into the model manually. The RC slab,

which this study focuses, is similar to the one shown in Figure 2 and the cased charge

considered is shown in Figure 15. This type of explosive is commonly known as a pipe bomb.

Figure 15 Dimensions of the cased charge in the study

8

Methodology for the Prediction of Combined Blast and Fragment Loading

It is important to pinpoint the parameters to calculate the combined blast and fragment

loading from a cased charge. From past research, these important parameters are the mass of

an explosive charge and casing and the stand-off distance of the charge from the target. The

steel pipe surrounding the explosives within has an external diameter of 0.2m and a thickness

of 0.04m. The height of the cased charge is 0.6m. Assuming that the steel and explosives

densities are 7,860kg/m3 and 1,600kg/m

3, the mass of the casing and explosives are 94.8kg

and 10.9kg respectively.

Other than the casing and explosive charge mass and the stand-off distance, it is important to

identify the spread of the fragment load. Unlike blast loading, which affects the entire

exposed surface, the area in which the fragments are projected is limited. This is observed in

one of the tests conducted by the Norwegian Defence and Estates Agency [4]. It is observed

that the angle of fragments spread from the casing of a 155mm artillery shell at a stand-off

distance of 1m is approximately 15 (see Figure 16). This angle will be used in the

subsequent calculations.

(a) (b)

Figure 16: Side view of the test (a) before and (b) after detonation

Figure 17 showing the different stand-off distances and fragment-targeted segments

To find the stand-off distances, a diagram of the slab and charge positions were drawn. With

differing horizontal displacements of the fragments from the charge (bases of the triangles in

Figure 17), a constant vertical height of 2m (all the triangles share the same vertical height)

and the 15 fragment angle found in Figure 16 (labelled in Figure 17), a variation of stand-off

distances (hypotenuse of the triangles) can be obtained. Figure 17 is an example of the slab

divided into 6 segments (1 triangle per segment) and will be important for the upcoming

section; Orientation of the bomb.

~15o

9

Figure 18 Pressure-Time history of fragment loading

As described in preceding sections, parameters to define blast loading can be derived from

charts such as the one shown in Figure 12 and computation software such LS-DYNA can

calculate the loading automatically. This is not so for fragment loading, which has to be

derived. The data required for the fragment loading are the peak pressure, estimated time of

arrival of the fragments (ETA), the loading duration (to) and the estimated time of termination

of the fragment loading (ETT). The graph in Figure 18 shows the relationship between these

properties.

To find the peak pressure, we will need to calculate the area underneath the graph and blast

duration. The area underneath the graph is equivalent to the fragment impulse IM. This can be

derived based on Equation 1 in which IO is bare charge impulse and M is casing mass [5]. IO

can be derived based on the scaled distance from Figure 12.

√

To find the loading duration, we need to find the Equivalent Bare Charge mass (EBC) for the

pipe bomb. To find this mass, we have to use the modified Fisher Equation [6]. A research

study done by Hartmann & Rottenkolber [7] has shown that for cased charges with thick and

brittle casings whereby their casing to charge mass ratios

are greater than 2, the modified

Fisher equation (as shown in Equation 2 below) could make good predictions of the EBC.

( [

( ⁄ )

])

Based on the EBC and stand-off distance, the loading duration to can be obtained from Figure

12. By using

, which is the inverse formula for the area of a triangle, the peak pressure

can be obtained. To obtain the ETA, we need the stand-off distance and the impact fragment

velocity VoI which can be found using Gurney’s equation [8]. The impact fragment velocity

can be expressed as [

]

where VoI is the initial fragment velocity and

G is the Gurney explosive energy constant. For this study, TNT is used hence the Gurney’s

constant value is approximately 2.44 km/s. The ETA of the fragments is calculated using

and it varies per segment. The ETT is the summation of to and the ETA.

10

Orientation of the bomb

Figures 19(a) and 19(b) below show the 2 different orientations of the pipe bomb. The

calculated fragment spread angle is used to find the segments the fragments are hitting after

detonation. As aforementioned, the linear distance from the charge core to the centre of a

segment is used as the stand-off distance, resulting in variations of fragment impulse values

per segment. In reality, these variations are significantly more diverse and unpredictable.

(a) (b)

Figure 19 showing the different orientations of the pipe bomb

The loading condition in Figure 19(b) resulted in more damage and z-displacement than the

other position. Figures 20(a) and 20(b) shows the damage of the loading on the slabs in

Figure 19(a) and 19(b) respectively and Figure 21 shows the z-displacement variation. Since

the affected area is greater in Figure 19(b) than Figure 19(a), it will be logical for more

damage and deflection increase in Figure 20(b) compared to Figure 20(a).

(a) (b)

Figure 20 Damage of the soffit of the slabs with different orientations of the bomb

Figure 21 Midspan displacement histories of the slabs with different orientations of the

bomb

Number of segments of the loading area

For each orientation, the number of segments are varied; 6 & 13 segments for the slab in

Figure 19(b) and 1, 6 & 10 segments for the slab in Figure 19(a). 10 segments were used

rather than 13 segments due to the high percentage error when reading off the fragment

impulse from the graph in Figure 12.

3m

11

For the orientation in Figure 19(b), the difference in the number of segments had very little

effect on the amount of stress and z-displacement; as seen in Figure 24. The same goes for

Figure 19(a) with the exception of the slab with only 1 segment; the z-displacement is greater

than the other 2 curves, 6 & 10 segments, as seen in Figure 23. Figures 22(a) & 22(b) shows

the difference in the stress fractures of the slab in Figure 19(a) with 1 segment and 6

segments respectively.

(a) (b)

Figure 22 Damage of the soffit of the slabs with different number of affected segments

Figure 23 Midspan displacement histories of the slabs with the bomb orientation in

Figure 19(a) but different number of affected segments

Figure 24 Midspan displacement histories of the slabs with the bomb orientation in

Figure 19(b) but different number of affected segments

The z-displacement decreases as the number of segments increases due to the corresponding

reduction in the average fragment impulse. However, after a certain number of segments,

there is almost zero change in the z-displacement; a graphical plateau. This probably explains

the results mentioned above.

12

CONCLUSION

From the results and the data from the simulations, we can conclude that the combined blast

and fragment loading does more damage to the RC slab than blast loading alone. The earlier

section on blast loading has also showed that by adding more rebars and having fixed

supports, the RC slab can absorb more damage from loading and deflects less than an

ordinary RC slab.

However there are still areas of improvement for this research such as the software used.

Only LS-DYNA and PrePost were used in this research thus it is unknown if other

computations will yield similar results due to the different equations they use for calculations.

In addition, only Grade 35 Concrete and Grade 460 Rebars were used thus the responses for

other grades of concrete and rebars against loading were not covered by this research.

ACKNOWLEDGEMENTS

I would like to thank my mentor Kang Kok Wei from Defence Science and Technology

Agency (DSTA) for his guidance and support throughout this attachment as well as teaching

me information and concepts of explosive as well as material engineering. I would also like

to thank the other DSTA and YDSP people for showing me what the DSTA does and what its

family enjoys as well as given me this meaningful research opportunity.

13

REFERENCES

1. WIKKI, Consultancy and Software Development in Computational Continuum

Mechanics Image Source: http://wikki.gridcore.se/oldstuff/expertise-in-complex-physics

2. StudyBlue, Structures at New Jersey Institute of Technology Image Source:

https://www.studyblue.com/notes/note/n/structures/deck/6636267

3. Research Online, University of Wollongong, The state of the art of explosive loads

characterisation, 2007, pg 12, Image Source:

http://ro.uow.edu.au/cgi/viewcontent.cgi?article=7176andcontext=engpapers

4. Langberg, H, Kasun III – External Charges, Presentation in Klotz Group Fall 2008

Meeting, 2008

5. Hutchinson, M. D, Combined Blast and Fragment Impulse – A New Analytical

Approach. Military Aspects of Blast and Shock. Bourges, France, 2012

6. Hutchinson, M. D, The Escape of Blast from Fragmenting Munitions Casings.

International Journal of Impact Engineering, 185-192, 2009

7. Hartmann, T, and Rottenkolber, E, The Trouble with Cased Explosives in the

Determination of Design Loads for the Structural Analysis. Design and Analysis of

Protective Structures. Jeju, Korea, 2012

8. [8] Gurney, R, The Initial Velocities of Fragments from Bombs, Shells and Grenades.

MD, USA: Army Ballistic Research Laboratory, 1943

14

ANNEX

The sample of the file written by WordPad to specify values into the mesh.

*KEYWORD

$Units: kg;m;sec;Pa / (ton;mm;sec;MPa)

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*TITLE

10kg@3m Blast

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*INCLUDE

Mesh

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*CONTROL_TERMINATION

$ *ENDTIM ENDCYC DTMIN ENDENG ENDMAS

0.05 0 0.0 0.0 0.0

*CONTROL_TIMESTEP

$ DTINIT TSSFAC ISDO TSLIMT DT2MS LCTM ERODE MS1ST

0.0 0.67 0 0.0 0.0 0 0 0

$ DT2MSF DT2MSLC

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

$ $

$ DATABASE CONTROL FOR BINARY $

$ $

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*DATABASE_BINARY_D3PLOT

$ *DT/CYCL LCDT BEAM NPLTC

0.001 0 0 0

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*PART

Concrete

$ *pid *secid *mid eosid hgid grav adpopt tmid

1 1 1 0 0 0 0 0

*PART

Rebar

$ pid secid mid eosid hgid grav adpopt tmid

2 2 2 0 0 0 0 0

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8 1

*SECTION_SOLID

$concrete

$ *secid elform aet

1 1

*SECTION_BEAM

$rebar

$ *secid elform shrf qr/irid cst scoor nsm

2 1 1 1 1

$ *ts1 *ts2 tt1 tt2 nsloc ntloc

0.025 0.025 0 0

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

$ $

15

$ MATERIAL CARDS $

$ $

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*MAT_Concrete_Damage_Rel3

$concrete

$ *MATID *RO PR

1 2300 1.900E-01

$ f't *A0 A1 A2 B1 OMEGA A1F

0.00E+00 -40E+06 0.00E+00 0.00E+00 0.000 0.00 0.00E+00

$ sLambda NOUT EDROP *RSIZE *UCF LCRate LocWidth NPTS

0.00E+00 0.00E+00 0.00E+00 39.37 145E-06 7201 0.00E+00 0.00e0

$ Lambda01 Lambda02 Lambda03 Lambda04 Lambda05 Lambda06 Lambda07

Lambda08

0.00E+00 0.00E+00 0.0E-00 0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.00E+00

$ Lambda09 Lambda10 Lambda11 Lambda12 Lambda13 B3 A0Y A1Y

0.00E+00 0.00E+00 0.000e0 0.000e0 0.000e0 0.00E+00 0.00E+00 0.00E+00

$ Eta01 Eta02 Eta03 Eta04 Eta05 Eta06 Eta07 Eta08

0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.000E+0 0.00E+00 0.00E+00 0.00E+00

$ Eta09 Eta10 Eta11 Eta12 Eta13 B2 A2F A2Y

0.00E+00 0.00E+00 0.00E+00 0.00E+00 0.000E+0 0.00E+00 0.00E+00 0.00E+00

*MAT_PLASTIC_KINEMATIC

$steel

$ *MID *RO *E PR *SIGY ETAN BETA

2 7850 200E+09 0.30 460E+06 0.00 0.0

$ SRC SRP FS VP

30 5

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

$ $

$ DIF CURVE CARDS $

$ $

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*DEFINE_CURVE

$ LCID SIDR SFA SFO OFFA OFFO DATTYP

7201 0 1.0 1.00

$ Strain-Rate Enhancement

-3.000E+04 1.085E+01

-3.000E+02 1.085E+01

-1.000E+02 7.526E+00

-3.000E+01 5.038E+00

-1.000E+01 3.493E+00

-3.000E+00 2.338E+00

-1.000E+00 1.621E+00

-1.000E-01 1.496E+00

-1.000E-02 1.380E+00

-1.000E-03 1.273E+00

-1.000E-04 1.175E+00

-1.000E-05 1.084E+00

0.000E+00 1.000E+00

3.000E-05 1.000E+00

1.000E-04 1.035E+00

16

1.000E-03 1.105E+00

1.000E-02 1.180E+00

1.000E-01 1.260E+00

1.000E+00 1.345E+00

3.000E+00 1.388E+00

1.000E+01 1.436E+00

3.000E+01 1.482E+00

1.000E+02 2.214E+00

3.000E+02 3.193E+00

3.000E+04 3.193E+00

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

$ $

$ BLAST LOAD CARDS (pressure) $

$ $

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*LOAD_BLAST

$ *wgt *x0 *y0 *z0 tbo *iunit *isurf

10 1.50 0.50 3.2 0.0000 2 2

$ cfm cfl cft cfp death

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*LOAD_SEGMENT_SET

$ *ssid lcid sf at dt

1 -2

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*DEFINE_CURVE_TITLE

Dummy Curve for LOAD_BLAST

$ lcid sidr sfa sfo offa offo dattyp

66 0 0.000 0.000 0.0 0.0 0

$ abscissa (time) ordinate (value)

0.000000E+00 0.000000E+00

1.000000E+05 0.000000E+00

*DEFINE_CURVE_TITLE

Dummy Curve for LOAD_BLAST

$ lcid sidr sfa sfo offa offo dattyp

67 0 0.000 0.000 0.0 0.0 0

$ abscissa (time) ordinate (value)

0.000000E+00 0.000000E+00

1.000000E+05 0.000000E+00

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

$ $

$ BOUNDARY CARDS $

$ $

$---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8

*BOUNDARY_SPC_SET

$Pinned

$ nsid cid dofx dofy dofz dofrx dofry dofrz

1 0 1 1 1 0 0 0

*END

0.12m