7.01

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truts

proprietary bracing struts

HDMBS (10kN accidental load)

MBS (with screws extended less than 300mm + 10kN accidental load)

MBS (with screws extended less than 450mm + 10kN accidental load)

MBS (no restriction on screw extension + 10kN accidental load)

JC40 (5kN accidental load)

LMBS (10kN accidental load)200

100210 3 4 5 6 7 8 9 10 11 12 13

300

400

500

600

700

safe

wor

king

load

(kN

)

length (m)

combination with double-acting hydraulic bracing frames for the strutting of excavations. The most commonly used struts are:

• JC40 bracing strut - originally developed for use in trench boxes

• light duty mechanical bracing strut (LMBS)

• standard mechanical bracing strut (MBS)

• standard mechanical bracing strut with higher strength screw units - normally referred to as heavy duty mechanical bracing strut (HDMBS)

• super bracing strut (SBS)

All the struts are modular with mechanical screw adjustment so they are not at risk of hydraulic failure.

The prop bodies for light duty mechanical, standard mechanical and super bracing struts consist of square sections as opposed to circular sections for safer handling and storage on site and during transportation - the square section bodies minimise the risk of rolling.

Forchart below:

Similar information in tabular form appears on pages 7.03, 7.05, 7.06 and 7.07.For information on the super bracing strut see pages 7.08 onwards.

Proprietary Bracing Struts - Allowable Loads(except Super Bracing Struts - see page 7.10)

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truts

light duty mechanical bracing strut (LMBS)

standard mechanical bracing strut (MBS)

heavy duty mechanical bracing (HDMBS)

self weight accidental load of 10kN

axialloadP

The above struts are intended to sustain allowable axial compression loads as shown on page 7.01. Similar performance data in tabular form is set out on pages 7.05, 7.06 and 7.07.

Performance Criteria1. The allowable axial compression loads are based on:

a) relevant parts of BS449 : 1969 : Part 2 b) testing

2. The performance data assumes that the make-up of the struts is in accordance with the user information

in particular:

a) The struts are used in combination with one of Mabey Hire Services’ Universal Column waler rails, i.e. U.C. 203x203x52kg/m Shaftbrace rail (LMBS and MBS struts only) U.C. 254x254x107kg/m Multibrace rail U.C. 254x254x107kg/m Super Shaftbrace rail

b) The strut is connected with the correct connector plate and clamp arrangement such that the centre-line of the strut is aligned with the web of the waler rail and end restraint is provided.

c) The st

3) The performance data below allows for:

a) Axial loading in combination with primary bending due to self weight

b) An accidental load imposed at any point along the strut equivalent to a static point load of 10kN as recommended in CIRIA Special Report 95 (December 1993).

c) Secondary moments resulting from:

• eccentricity of axial load • an allowance for accumulation of debris on the strut • an allowance for initial strut crookedness

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7.05 7.03

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truts

light mechanical bracing strut(LMBS)

Strut Code No. (kg) (mm)

(kN)

272 1890 - 2690 200

322 2390 - 3190 200

342 2890 - 3690 200

392 3390 - 4190 200

382 3890 - 4690 200

432 4390 - 5190 200

482 4890 - 5690 200

502 5390 - 6190 200

472 5890 - 6690 200

522 6390 - 7190 200

572 6890 - 7690 200

592 7390 - 8190 200

:

shaftbrace : 203 x 203 U.C. ormultibrace : 254 x 254 U.C. orsuper shaftbrace : 356 x 368 U.C.

180 x 180 x 8thkSquare Hollow Section

strutsquare to rail

strut length(between walings)

8 No. M20 x 75 longbolts per connectionmaximum screw

extension 400mm

connector plate( MBSP-006 - use with shaftbrace MBSP-007 - use with multibrace MBSP-008 - use with super shaftbrace)

clamp platestop and bottom(MBSP-009)

4 No. M20 x 60 long Gr10.9countersunk sockethead set screws andnuts per connection

2 No. M20 x 75 long orM20 x 90 long boltsper connection