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Basketball Court Slab on Grade Structural engineering general

23 12 2004 nbsp 0183 32 For your 5 quot slab the joints should be spaced at 10 to 12 feet on center both ways This will allow smaller amounts of movement at each joint Joints should be cut to depth of 1 25 inches and should be cut the day of placement not the day after Then do as JAE said quot cure the hell out of it quot and let the slab sit for a couple of weeks You ll be able to look into the joint and

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Control Joints in Structural Slab on grade Structural

16 11 2002 nbsp 0183 32 Hello fellow Florida engineer I would suggest the following to control cracks in the concrete slab 1 I suggest a sand blanket of 3 inches thick under the slab 2 Vapor barrier of 6 mills is a good idea 3 Use concrete with strength of 3500 psi to 4000 psi and water cement ratio of 0 45 or less 4 Use of fiber mesh is good to minimize the hair line cracks

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control joint spacing Topic American Concrete Institute

01 03 2019 nbsp 0183 32 Shrinkage Based Analysis for Control Joint Spacing in Slabs on Ground Publication Structural Journal Date 5 1 2002 Ultimate Strength Design Charts for Columns Controlled by Tension Publication Journal Proceedings Date 12 1 1957 Search all Articles on control joint spacing 187 Practice oriented papers and articles ON CONTROL JOINT

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Design Guide 11 Floors Slabs on Ground for Concrete Structures USDA

floor type from which the designer can select the appropriate steel schedule based on joint distance and slab thickness The tables show common bar sizes and spacing that establishes a basic design using a common range or distance for the steel schedule and spacing Formulas are included that allow the designer an option to develop a site specific design for the steel

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Maximum Joint Spacing Calculator ACPA

Longitudinal joint spacing on two lane and multilane concrete pavements typically is about 10 to 13 ft 3 0 to 4 2 m This tool provides an estimate of the maximum allowable joint spacing based on the slab thickness and the subgrade subbase used two of the variables with the most prominent effect on joint spacing requirements

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Concrete slabs and control joints BRANZ Build

shrinkage control joints or between shrinkage control joints and a free joint should be between 2 1 and 1 1 so no bay should be more that 6 215 6 m Supplementary steel may be placed in irregularly shaped concrete floor slabs in positions shown in NZS 3604 2011 Figure 7 18 but must not be installed across shrinkage control joints Laying flooring over top

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CIP 6 Joints in Concrete Slabs on Grade

a The maximum joint spacing should be 24 to 36 times the thickness of the slab For example in a 4 inch 100 mm thick slab the joint spacing should be about Saw cut Tooled Wall or Column Expansion joint material Slab on grade Column Contraction joints intersect at diagonals of the square Form openings which will be filled after floor has hardened

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Are Sawcuts Required in My Slab Part 1 Commercial Slabs on VERTEX

22 02 2019 nbsp 0183 32 Contraction Joint Spacing ACI 360R 10 ACI 360 as referenced by ACI 318 as referenced by IBC includes Figure 6 6 for the recommended CJ spacing for unreinforced concrete slabs on ground as follows CJ Spacing Graph from ACI 360 Fig 6 6 Note that CJ spacing in a 4 inch slab should be between 8 feet and 13 feet An 8 inch slab or thicker is

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Typical Long Bay 60 Construction Coreslab Structures

Unbonded post tensioning strands in slab areas to control temperature and shrinkage cracks also in bottom of beams for load carrying capacity Joint sealant At precast to precast joints and pour strip tooled joints At topping slab tooled joints aligned with precast to precast joints At construction joints Expansion joint 300 –350 spacing 300 –350 spacing 300 –

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DUCTILCRETE 174 engineered slab systems GCPAT

DUCTILCRETE 174 engineered systems extend control joint spacing allowing for Reduced curling and associated maintenance of concrete floors Increased load bearing capacity More flexibility in space usage and layout Fewer Joints Backed by a five year warranty from your DUCTILCRETE 174 licensed contractor these unique engineered systems support a wide range

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SLAB ON GRADE REINFORCING DESIGN PDHonline com

This spacing may or may not coincide with the desired joint spacing of an unreinforced concrete slab With some limitations reinforcement for slabs can be sized using the Subgrade Drag Theory in order to increase the spacing of control or construction joints The result is a lightly reinforced slab designed to offset the effects of temperature and shrinkage of the concrete

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Control of Random Cracking in Concrete Residential Pavements

Changes to the joint details spacing and reinforcement were considered necessary to limit what is now referred to in the Standard as random crack widths for which the performance limits have been reduced from 1 5 mm to 1 0 mm for consistence with other Standards that cover residential concrete work The question remains as to what is considered an acceptable random crack

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Concrete Jointing and Details Thickness is Only the Start

joint spacing due to load transfer considerations Joint Spacing Rules of Thumb for Jointing amp Slab Dimensions Spacing Recommendation of 2 5 times the depth in feet For example 4 thick 10 maximum 4 x 2 5 Panel shall be kept as square as possible L W of 1 189 1 Maximum length to width ratio Slab Length amp Related Design Factors Experience indicates that there is an

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CONTROL JOINTS FOR CONCRETE MASONRY WALLS TEK 10

Maximum control joint spacing per Table 1 st nd 4 NCMA TEK 10 2C each side or a horizontal bond beam could be used as shown in Figure 2d For best performance the vertical reinforcement should be placed in the cell immediately adjacent to the opening However due to congestion in the cell at this location vertical reinforcement is sometimes placed in the second

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Joints in Concrete Slabs on a Grade What why

The maximum joint spacing should be 24 to 36 times the thickness of the slab For example in a 4 inch 100 mm thick slab the joint spacing should be about 10 feet 3 m It is further recommended that joint spacing be limited to a maximum of 15 feet 4 5 m All panels should be square or nearly so The length should not exceed 1 5 times the width

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Reinforcements for Slabs on Ground Crack Width

These are the joint spacing and the thickness of the slab Or we can tell the crack width control is a function of joint space and slab thickness A minimum steel ratio of 0 5 of the slab cross section is recommended so that the saw

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How to Cut Control Joints in Concrete Slab The Constructor

The spacing of the joints is in the range of 24 to 36 times the thickness of the concrete slab If you are using high shrinkage concrete you might want to decrease the cut spacing The factors that determine the location of control joints are Continuity The joints must be continuous Square Pattern They must form segments in square patterns Reinforcement The ideal

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Concrete Slab Load Capacity Chart Recipes

With some limitations reinforcement for slabs can be sized using the Subgrade Drag Theory in order to increase the spacing of control or construction joints The result is a lightly reinforced slab designed to offset the effects of temperature and shrinkage of the concrete ACI 360 quot Design of Slabs on Grade quot refers to this as a Type B slab

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Expansion Joints in Concrete why when how Structural Guide

04 11 2019 nbsp 0183 32 Expansion joints in concrete should be provided in structures to accommodate expansions due to the thermal effects Concrete expands when it absorbs the heat and shrinks when the heat is a loss There are different guidelines to design the width of the expansion joint depending on the type of structure The method of designing an expansion joint elaborate

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CONCRETE ACCESSORIES JOINT DOWELING SYSTEMS Sika

SLAB DEPTH Speed Plate 174 DOWEL DIMENSIONS PLATE DOWEL ON CENTER SPACING 5 6 1 4 thick X 4 wide X 6 long 18 7 8 3 8 thick X 4 wide X 6 long 18 9 11 3 4 thick X 4 wide X 6 long 18 Note Values are based on a maximum joint opening of 0 20 reducing labor and material costs The spacing chart

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Concrete Mixture Shrinkage Potential Concrete Construction

06 09 2012 nbsp 0183 32 ACI Committee 360 Design of Concrete Slabs on Ground includes a chart See Fig 1 that helps determine the maximum joint spacing Joints are typically recommended on column lines to relieve the restraint caused by column penetration The chart helps determine how many joints are needed between columns This chart is based on the shrinkage potential

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Slab on Grade Concrete Carroll s Building Materials

Control Joints Contraction Joints are formed sawed or tooled grooves which weaken the concrete so it cracks at the joint These joints accommodate the movement caused by temperature changes and drying shrinkage Joint Spacing is Critical – As shown in the drawing above an un jointed slab will usually develop a similar pattern of uncontrolled cracking cause

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302 1R 04 Guide for Concrete Floor and Slab Construction

9 8 Protection of slab during construction 9 9 Temperature drawdown in cold storage and freezer rooms 9 10 Joint filling and sealing Chapter 10 Quality control checklist p 302 1R 61 10 1 Introduction 10 2 Partial list of important items to be observed Chapter 11 Causes of floor and slab surface imperfections p 302 1R 62

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Control Joints in Concrete When To Cut amp Spacing

01 07 2021 nbsp 0183 32 CONTROL JOINT SPACING Space joints in feet no more than 2 3 times the slab thickness in inches A 4 quot slab should have joints 8 12 feet apart When arranging joints skilled contractors will often use them to create an attractive diamond pattern If your concrete will be stamped ask about the best ways to avoid interrupting the pattern with control joints

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Placing Joints in Concrete Flatwork Why How and When

Joints are commonly spaced at distances equal to 24 to 30 times the slab thickness Joint spacing that is greater than 15 feet require the use of load transfer devices dowels or diamond plates Figure 1a Joint Spacing in Meters Figure 1b Joint Spacing in Feet Contraction joints may be tooled into the concrete surface at the time of placement

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ACI 224 3R 95 Joints in Concrete Construction Lauw Tjun Nji

4 4 Bridges without expansion joints Chapter 5 Slabs on grade p 224 3R 20 5 1 Introduction 5 2 Contraction joints spacing of joints and the development of further rational ap proaches Diverse and sometimes conflicting guidelines are found for joint spacing Table 1 1 reports various recommendations control joint is not included in this list of joint

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Placing Joints in Concrete Flatwork Why How and

Contraction control joints are placed in concrete slabs to control random cracking A fresh concrete mixture is a fluid plastic mass that can be molded into virtually any shape but as the material hardens there is a reduction in volume

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Maximum Joint Spacing Calculator ACPA

For jointed plain unreinforced concrete pavement JPCP the maximum allowable joint spacing or slab length depends on variables such the slab thickness concrete aggregate used cement content subgrade subbase used and climate In most areas the typical maximum transverse joint spacing for JPCP used in applications such as streets roads and highways is about 15

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Control Joint Placement JAN Meridian 174

08 03 2018 nbsp 0183 32 For straight solid walls the spacing between control joints is determined by the width of the control joints and the type of sealant however the walls should not exceed 40 ft 12m If a 3 8 to 1 2 10 12mm wide joint is desired then the spacing between joints is approximately 25 ft 8m which also corresponds to the column spacing This is based on a

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Guide to Design of Slabs on Ground WordPress com

7 4 Maximum joint spacing Chapter 8 Design of slabs reinforced for crack width control p 360R 34 8 1 Introduction 8 2 Thickness design methods 8 3 Reinforcement for crack width control only Chapter 9 Design of shrinkage compensating concrete slabs p 360R 34 9 1 Introduction 9 2 Thickness determination 9 3 Reinforcement 9 4 Other