TRUSSES

TRUSSES

ROD TRUSSES

U - BOLT TRUSS

U - BOLT TRUSS

WHAT IS WRONG WITH THIS PICTURE ?

TRUSS PROBLEMS

TRUSS MISAPPLICATION

DYWIDAG TENSIONABLE SLING

ONE PIECE SLING

ONE PIECE INSTALLATION

ONE PIECE CABLE SLINGS

TWO PIECE CABLE TRUSS OR SLING

6 x 16 LOOP PLATE

BLOCK & BARREL-WEDGES

JACK OR WRENCH

TIGHTENING UP TRUSS

CLOSEUP OF BARREL & WEDGE

FAILURE BROKEN WIRE

WEAK ROOF SLING

PRESSURE vs APPLIED LOAD

TRUSSES USED ON TAILGATES

CABLE BOLTS

WORST CASE

EXCEL CABLE BOLT PASSIVE SYSTEM

NON-TENSIONED CABLE BOLT

CABLE CROSS-SECTION

• DIAMETER– 0.6 TO 0.9 INCH

• STRENGTH– GRADE 270

BIRDCAGE FOR MIXING

HOUSING UNIT

WEDGE

HOUSING CLOSE UP OF TEETH IN WEDGE ANCHORING INTO WIRE ROPE

SPECIAL THREADS OR TEETH

• DYWIDAG

• CABLE BOLT

• ACTIVE

• SYSTEM

TENSIONING CABLE BOLT

TENSIONED CABLE BOLT

POST TENSION TENIONABLE CABLE BOLT

16’

In the area 150’ immediate outbyroof fall area, center cable bolt is 22’ long.In the other area, 16’ long.

0.7” JM Post Tension cable bolt

In the area 150’ immediate outbyroof fall area, maximum row spacingis 4’. In the other area, maximum row spacing is 6’

T-5 channel

EPOXY COATING

CentralStrand

GritSurface

OuterStrand

EpoxyCoating

STRENGTH OF CABLE BOLTS

CABLE SIZE YIELD

0.6 INCH DIA 30 TONS

0.7 INCH DIA 40 TONS

0.9 INCH DIA 58 TONS

GRAPH OF (0.6 INCH ) EXCEL CABLE BOLT

FAILURE

CABLE BOLT PROPERTIES• STEEL GRADE 270• LOW VISCOSITY

RESIN ( EASIER TO INSERT CABLE )

• STIFFNESS OF CABLE IS CONTROLLED BY LENGTH OF RESIN ( SHORTER THE FREE LENGTH, THE STIFFER THE CABLE )

RESIN

FREELENGTH

COMMON CABLE PLANSSUPPLEMENTAL SUPPORT

• HOLES USUALLY 1” - 1 3/8” DIA

• 12 - 16 FT LENGTH

• 4 - 5 FT RESIN LENGTH

– ( ONE MINE, 2 FT RESIN )

• 4 CABLES PER ROW

• 4 - 6 FT ROW SPACING

• SURFACE CONTROL , MATTS

CABLE BOLTS USED AS PRIMARY SUPPORT

CABLE BOLTS USED AS PRIMARY SUPPORT

LONGWALL GATE ENTRIES

MINERS WITH INTERGAL BOLTERS

ENTRY WIDTH 16.5 - 17 FT

JENNMAR CB CABLE BOLTS

SHELL 4 FOOT FROM END

4 FOOT RESIN

TWO CABLE BOLTS, MATT & CENTER BOLT

TYPES OF SUPPLEMENTAL SUPPORTS USED WITH CABLES,

USED AS PRIMARY SUPPORT

TRUSSES WITH CRIBS OR PROPSETTERS AT INTERSECTION

OR

TWO CRIBS, PROPSETTERS ORLINK-N-LOCKS

ON 6 FT EDGE TO EDGE

CABLE PLAN FOR HIGH HORIZONTAL STRESS

0.7 0.9

THE END