Technical References

Example shows shores used in awkward places where tower frames are unsuitable. See Figure 42, below.

Fig. 42

Fig. 42a

Fig. 42b

Note: All post shores must be erected plumb and braced if subjected to lateral loads. As there are many Manufacturers of Post Shores consult specific load charts for kind, make and size and loads.

Example Single Post Shores can be used to support strings and share the load with frames. See Figures 44.

Fig. 44

Fig. 44a

Fig. 44b

Example: Single Post Shores are also used for extra support inside frame towers. See Figure 45, below

Fig. 45

Fig. 45a

Fig. 45c

Shores have many other uses although the Super Hi-Lite System is now replacing many older, outdated methods, and taking the pace of the Single Post Shore in numerous applications, yet the Single Post Shore still has many good uses such as, the reshoring of the slabs.

Back to top

• W = Width of Slab Area
• L = Length of Slab Area
• F.H. (Floor Height) = Top of Slab to Top of Slab

EXAMPLE ONLY

Example: Height of Leg - 10' (1 - 4' and 1 - 6' High Frame)

Maximum Leg Capacity -- 11,600 lbs.

Example above -- Height of Frame and Extensions -- 11'10"

1. Frame requirements preferred 1 - 4' and 1 - 6' plus 30" extension tube extended 14" on bottom and Screwjacks on top. Capacity as per Table #4 = 11,600 lbs. (Table 4, and not Table 5, is used because extension tube is only replacing Jack as extension is only 14")

2. Frame requirements alternate 1 - 6' frame plus 48" extension tubes on bottom, plus 48" Extension Tubes plus Screwjacks on top. Capacity as per Table 5 = 4500 lbs.

EXAMPLE ALTERNATE

Showing the use of one 6' frame and extension tubes instead of one 4' frame and one 6' frame. Also how to calculate load capacity.

NOTE: 321/4" = Lower Extension Tube Extension

14" = Jack Replacement (if Jack were used) Height of Extension Tube, for Load Calculating Purposes = 18".

Use Table number 5, Section B at 20" extension, as top extension tube governs because there is no Jack at bottom and therefore 14" can be deducted from extension of 32 1/4" making bottom extension for capacity purposes only 18" long, which is shorter than 20" at top, and as extension tubes are used at the top and more than 14" (testing length) at the bottom, you must use Table number 5 Section B which gives a capacity of 5000lbs. per leg.

A big reduction from using a 2 frame high tower (interbraced) with a capacity of 11,600 lbs.)

Back to top

• T = Thickness of slab in inches
• L.L. = "Live Load" (Placing of concrete, men & equipment) Use 40 lbs. per square foot (lb./ft.2)
• Wt. FM = Weight of forms Use 10 lbs. per square foot (lbs./ft.2)
• L.L. & Wt. FM. = Use 50 lbs. per square foot (lb./ft.2)
• Wt. Concrete = Weight of Concrete Use 150 lbs. per cubic foot (lb./ft.2)
• T/12 x Wt. Concrete + Wt. FM. = Weight per square foot of concrete slab

EXAMPLE 9" SLAB WEIGHTS:

• 9/12 x 150 lbs. = 112.5 lbs. per square foot (lb./ft.2)
• Plus 50 lbs. L.L. & Wt. FM. = Total Weight of 9" slab
• 112.5 + 50 = 162.5 lbs. per square foot' for 9" slab= 162.5 lbs./ft.2

Back to top

• W = Width of Slab area supported
• L = Length of Slab area supported
• W x L x Weight of Slab = Load per leg
• 5' 0" x 8' 0" x 162.5 lb/ft2 = Load per leg
• 40 sq.ft. x 162.5 lb/ft2 = 6500 lbs. Compare to leg capacity eg.

Capacity of leg in example = 11,600 lbs. (considerably more) which suggests frames can be spaced further apart. Now see stringer and joist capacity if under loaded as per beam charts. Frames can and should be spaced further apart.

NOTE: The object is to get the load per leg close to the capacity of the leg as allowable. The ideal layout will maximize full leg capacity and full beam capacity, by following respective charts. Usually there are a number of layout designs to consider. Strive for the most economical way to make the Hi-Lite Shoring System perform to the best of its ability.

Back to top

• D = Depth of beam in inches
• W = Width of beam in inches
• L.L. = "Live Load" Placement of Concrete, Hen and Equipment Use 40 lbs. per square foot
• lb/ft2 = Pounds per square foot
• lbs/ft3 = Pounds per cubic foot
• Wt. = Weight of formwork. Use 101 lbs. per square foot (lb/ft2)
• L.L. & Wt. FM. = Use 50 lbs. per square foot (lb/ft2)
• Wt. Conc. = Weight of Concrete. Use 150 lbs. per cubic foot (lb/ft3)

D/12 x Wt. Conc. + L.L. + Wt. FM. x W/12 = Weight of Concrete Beam per Lineal Foot

36 x 150 lbs/ft3 + 50 lb./sq.ft. x 18 = Weight of Concrete Beam per Lineal Foot

450 lbs. + 50 lbs. x 1.5 = Weight of Concrete Beam per Lineal Foot

750 lbs. = Weight of Concrete Beam per Lineal Foot.

Back to top

• L = Length of Beam or Slab
• W = Width of Beam or Slab

EXAMPLE OF LAYOUT ONLY

Back to top

W x L x Weight of Slab = Load per leg for Conc. Slab 4'9" = 3.25

3.25 x 8 x 162.5 lbs/ft2 = Load per Leg for Conc. Slab only

4225 lbs. = Load per Leg for Conc. Slab only

TOTAL

Beam Load Per Leg + Slab Load Per Leg =Total Load Per Leg lbs. + 4225 lbs. - Total Load lbs. = Total Load Per Leg for above example

NOTE: Compare with leg and beam capacity. See load tables and beam charts. Increase or decrease leg spacing accordingly, try for maximum capacity.

Back to top

L x Weight of Conc. Beam per Lin. Ft./2 = Load/Leg for Conc. Beam

8 x lbs. = Load per Leg for Conc. Beam only

Back to top

L = Length of Concrete by 1' Wide

Load Per Foot Run on Stringer = L x 1' x Wt. per Foot of Slab

L x 1'0" x Wt. Conc. = Weight per Linear Foot on Stringer

8'0" x 1'0" x 162.5 lbs. Weight per Linear Foot on Stringer

1300 lbs. = Weight per Linear Foot on Stringer

(REFER TO BEAM CHART FOR LOAD CAPACITY PER LINEAR FOOT OVER SPAN)

Page says you can span over approx. 7.' with 2 spans. If you use 71/2" Beam Chart, Page you can span 8' on 2 spans and this will increase leg load which will have to be rechecked.

NOTE: Design for longest stringer span possible.

EXAMPLE SHOWS:

7' span is okay for 61/2" stringer beam with 9" slab 'using L/270 deflecting. Use deflection requirements required by builder, normally either L/360 or L/270. See Beam Charts Page 46-47 for 61/2" beam and Page 53-54 for 71/2" beam capacities, note different strengths.

NOTE: Layout measurements used in examples are for easy figuring only. They have no bearing on capacity of system.

Back to top

L = Length of Concrete by 1'

Wide Load per Foot Run of Joist = L x 1' x Wt. per Foot of Slab

L x 1'0" x Wt. Conc. = Weight per Linear Foot of Joist

1.6' x 1'0" x 162.5 lbs. = Weight per Linear Foot of Joist

260 lbs. = Weight per Linear Foot of Joist using 9" for Slab thickness

Refer to Beam Chart for load capacity per foot of span on 9" slab and Plywood Charts for spacing.

Plywood Chart on page 77 shows joist spacing must be under 24" without using 3/4" plywood so next module is 19.2".

Beam Charts pp 46, 47, 48 shows span could be 10' (if increased leg load is still within leg load limits.

Note: Design for longest joist span using permissible deflection requirements required by builder either L/360, L/270 or other. See Beam Charts Page pp46 - 48 for 61/2" beam and pp 53 - 55 for 71/2" beam, note different load capacities. When determining final layout of beam recheck leg loads.

NOTE: Layout measurements used in examples are for easy figuring only. They have no bearing on capacity of system.

Back to top

These basic load ratings are for installations where:

1. The shoring system is founded on an unyielding support, i.e. concrete slab, on grade or properly reshored or a sound, stiff soil mudsill system.
2. The formwork or other load being supported provides restraint against translation of the tower tops, and does not introduce lateral forces at the top of the upper jack plates.
3. The towers are installed to tolerances required by CSA S269.1 1975, as quoted below.

NOTE: For towers having to resist lateral loads, see Table 3, Page 40

VARIATION FROM PLUMB

TOLERANCES AS PER CANADIAN STANDARD ASSOCIATION S269.l 1975

Vertical load-carrying members shall be erected and maintained plumb within the following limits:

1. Plumb lines through any two points on the centre line of the vertical members and less than 10 feet apart vertically shall not be separated by more than 1/2 inch.
2. Plumb lines through any two points on the centre line of the vertical members shall not be separated by more than a ratio of 3/4 inch in 20 feet nor exceed 11/2 inches in the length of the vertical member over 40 feet.

NOTE: Configurations with interframe crossbracing are of higher basic capacity than those without; e.g., a single tier high tower has only one set of crossbraces, allowing the frame legs to buckle in the same direction where a 2 frame high tower "INTERBRACED" has three sets of bracing restricts this action. For clarification of inter-frame crossbracing, see Page 5, Figure 3. Also see Load Charts on Page 41.

Back to top

It is good shoring practice, and strongly recommended by Hi-Lite that Lateral stability/strength be provided for by the falsework deck structure, with loads being taken to elements of the existing permanent structure.

A second alternative is to provide additional bracing by means of a tube and clamp system, taking lateral loads to the permanent structure; or to mudsills or other suitable resisting elements. Where these approaches are not practical, the Super Hi-Lite System may be used to resist lateral loads, with an accompanying derating of the vertical capacity.

The calculated capacities in Table 3are based on a 2.5 factor of safety on both the vertical and lateral loads combined to comply with the existing 1975 CSA Canadian Standards Association Code S269.1.

Back to top

Back to top

For 1 to 3 frame (up to 20') high towers, with 12" maximum screwjack extension top and bottom or with jacks extended 12" at one end and extension tubes at the other, extended not more than 141/2" using 5 and 6 foot high frames.

NOTE: For towers using only 4' high frames up to four frames high, loads in this table can be increased by 15%.

Back to top

For 2 and 3 frame high towers using 4' and 6' high frames completely interbraced with extension tubes and jacks therein at one end extended 12" and with jacks extended 2" or extension tubes extended 141/2" in the other end replacing the jacks. (See maximum extension column.)

NOTE: One tier of 5' high frames can also be used in a tower and still interbraced if used as the bottom frame. If towers are not completely interbraced, reduce all capacities by 25%. For towers only one frame high with extension tubes and jacks as indicated below reduce all load capacities by 15% (as one frame cannot be interbraced). For towers using only 4' high frames. 2, 3, and 4 frames high completely inter- braced capacities can be increased by 15%.

NOTE:

30" Extension tubes must not be extended more than 20 1/2"

48" Extension tubes must not be extended more than 32 1/2"

Safety Factor - 2.5 based on ultimate test results

Back to top

TOTAL LOAD ON FRAME LEGS

• A = P1 + 1/2 WL
• B = P2 + 1/2 WL

The 3 conditions listed below must be satisfied:

1. Neither of the leg loads must exceed the load ratings for the frame as called out in Tower Capacities (page 41).
2. Neither P1 or P2 must exceed the ratings for the extension tubes as called out in Table 5 (page 41).
3. The aluminum beam used in conjunction with saddle beams must not be overstressed -- the maximum distributed load for varying lengths of saddle beam is as given in Table 6 below, for Hi-Lite 61/2" beam.

Back to top

Back to top