What is the average compressive and flexural strength of. It may be applied over most surfaces for a smooth finish before installation of permanent flooring. A study of factors affecting the flexural tensile strength. Kt23 reflects testing procedures found in aashto t 97. The results indicate that the flexural strength decreases as the cement content decreases in the mix. For the love of physics walter lewin may 16, 2011 duration. Substitute known values into nominal strength equation. A short period of drying can produce a sharp drop in flexural strength. Usg durock cement board is intended for use with tile, thin brick and exterior stucco coatings only. First and foremost, our concrete repair solution is versatile enough that it can be used on virtually any sound concrete surface. These equations are based on simplified tensile and. Usg durock brand x floor patch submittal sheet english. Flexuraltensile strength ratio in rocklike materials 221 wave velocity of the material, and the coordinates of each receiver, the event hypocenter can be estimated with a minimum of four sensor s.
The low water absorption combined with a high flexural strength makes vapour block an ideal water penetration barrier. The flexural strength is expressed as modulus of rupture mr in mpa. Considering that the concrete block pavements have a flexible behavior, the flexural strength test would be the main solicitation of each unit. Submittal data durock brand ne floor patch an easymixing, fastsetting concrete floor patch that needs no priming. I have installed durock in my kitchen floor, and after i glued and screwed it all down, i noticed that the floor is all on one plane, perfectly flat, except for an area that runs from one of the walls to a spot about three feet from the wall. Results are calculated and reported as the modulus of rupture. Flexural strength is one measure of the tensile strength of concrete.
The flexural strength is also easily carried out and more convenient than the crushing test for use in field, since in this test much small loads are required. When it comes to patching concrete surfaces, there are many advantages to using unique highperformance fast setting mortar hpfs. Usg durock brand speed selfleveling underlayment is ideal over. Trowelable high early strength floor repair patch durock brand tufskim floor patch is a fastsetting, fastdrying chemically hardening compound for use over interior gypsum underlayment and wood and concrete subfloors. A versatile, trowelable cementitious patching compound for interior use over concrete and approved wood subfloors. This fast drying patch may allow floor coverings to be installed in as little as 35 minutes. The flexural strength for various composites is shown in figure 6. Ideal for renovation projects, this economical usg durock brand ne floor patch provides a smooth skim coat for accepting floorcoverings. These equations are based on simplified tensile and compressive constitutive response and may be used. A versatile, trowelable, polymermodified cementitious patching compound for interior use over concrete and approved wood subfloors.
Bond strength after three days curing, the bond strength is greater than the inherent flexural strength of the concrete brick. Unique high performance fast set mortar is a commercialgrade, rapidsetting concrete repair material for patching concrete surfaces. Usg durock exg concrete repair patch is a highperformance. It is measured by loading 6 x 6inch 150 x 150mm concrete beams with a span length at least three times the depth.
Scope this method of test covers the procedure for determining the flexural strength of concrete by test of a sample beam with thirdpoint loading. Formulations are designed to provide high performance and excellent adhesion to similar and dissimilar substrates. Many factors have been shown to influence the flexural tensile strength of concrete, particularly the level of stress, size, age and confinement to concrete flexure member, etc. An astm designation number identifies a unique version of an astm standard. Prep underlayments provide strength beneath the surface featuring compressive. Flexural strength c947 psi indention strength d2394 1250 psi weight c473 floor i use 12 in durock. For the same specimen size, the strength determined will vary if there are differences in specimen preparation, curing procedure. Usg durock brand cement board 14 underlayment 14 usg durock brand cement board for.
Standard test method for flexural strength of concrete. Usg durock brand x floor patch is ideal for renovation projects and is easy to mix and apply. Usg durock brand x floor patch submittal sheet english cb816. For patching and repairing subfloor surfaces prior to installing all types of flooring. Usg durock ultracap floor underlayment performance flooring.
Flexural strength and toughness of steel fiber high. This has probably been asked hundreds of times and i will be reading other threads in the mean time. Cip 16 flexural strength concrete what is flexural strength. Many state highway agencies have used flexural strength, but are now changing to compressive strength or maturity concepts for job control and quality assurance of concrete paving. Flexural test on concrete significance, procedure and. Jan 07, 2018 for the love of physics walter lewin may 16, 2011 duration. Flexural strength, also known as modulus of rupture, or bend strength, or transverse rupture strength is a material property, defined as the stress in a material just before it yields in a flexure test. Increased flexural modulus and strength in swnt epoxy. Under what situations would it be acceptable to use 14 inch.
Is method of flexural strength of concrete testing, laboratory method. Table 1 compares the existing requirements and those raised by the new project. Steel framing must be 20gauge equivalent or heavier. Active standard astm c78 c78m developed by subcommittee. Flexural design of fiberreinforced concrete request pdf. Usg durock brand ultracap pro selfleveling underlayment. Usg durock x floor patch can be applied over engineerapproved, aparated exterior glue.
The results of flexural test on concrete expressed as a modulus of rupture which denotes as mr in mpa or psi. Find submittalready datasheets, sds, specs, icces reports. The assessment of concrete tensile strength must be made in its existing state without the removal. Therefore flexural strength testing is as important to test rather as compressive strength. Where the quality and strength of the stone is unknown, the floor must be engineered not to exceed the l720 deflection criteria, including live and dead design loads, for the specific joist spacing used. A study of factors affecting the flexural tensile strength of. Pdf flexuraltensile strength ratio in rocklike materials.
A simply supported concrete prism is loaded by two point loads placed at third points along the span. Installing durock correctly on a wood subfloor hearth. We recommend 14 in hardiebacker ensure subfloor is not. What is the average compressive and flexural strength of m30. The transverse bending test is most frequently employed, in which a specimen having either a circular or rectangular crosssection is bent until fracture or yielding using a three point. Winey a, a department of materials science and engineering, university of pennsyl vania. Standard test method for flexural strength of concrete using. Durock brand cement board with edgeguardtm offers enhanced. Most notable is frost testing en 12371, where a greater than 20% loss in strength is regarded as a failure. Standard test method for flexural strength of hydraulic. The tensile bond strength of the concrete subfloor over which usg durock.
Tile can be set just about anywhere, most commonly on floors and walls. Do not align hardiebacker cement board joints with plywood joints. Premixed floor patch helps repair cracks and holes in concrete, vinyl. Can i use a floor leveling product or should i build it up with thinset, let that dry, and then lay my tiles with more. There are 4 primary strengths that are very important for most civil and mechanical engineering applications of epoxy. Flexural strength testing can provide considerable insight into the quality of any stone material, which is why it is often used to compare specimens before and after they are subjected to cyclic weathering tests. Usg durock brand cement board installation guide english.
Usg durock x floor patch may be applied from featheredge to 12 in. Additionally, they feature superior thermal stability, exceptional chemical resistance and convenient cure schedules. Usg durock cement board is preferred by many applicators as a base for directly applied finishes, tile, stone and thin. However the important strength parameter for groundsupported slabs is flexural tensile strength routine flexural tensile testing of concrete is not common practice. Procedure overview this test method covers the determination of the flexural strength of concrete by the use of a simple beam with third point load ing.
It contains hydraulic cement, graded silica sand and performance enhancing additives. The assessment of concrete tensile strength must be made in its existing state. It tests the ability of unreinforced concrete beam or slab to withstand failure in bending. Usg floor prep usg pdf catalogs documentation brochures. Brittle coatings, such as epoxy coatings, are not recommended for use with usg durock cement board.
Floor coverings can be applied as soon as the durock floor patch is hard enough to work on. Having a larger surface area, aspect ratio and thinner, the slabs bend easily under wheel loads much like a beam. As per is 456 for estimating flexural strength,the relation between compress. A set of closed form equations for flexural design of fiberreinforced concrete are presented. Marble and natural stones must have sufficient flexural strength for use in flooring. Winey a, a department of materials science and engineering, university. Breakage occurred within the brick itself rather than at the bond interface between the topping crete and the surface of the brick. Wait until patch is thoroughly dry before installing the floor covering. For urethane and epoxy adhesives that are moisturesensitive or use moisture in their drying process, allow floor patch to dry overnight before applying adhesive. Durocks stateoftheart facility in woodbridge, ontario, canada is one of the largest of its kind in. Usg durock brand ultracap selfleveling underlayment is ideal over concrete. The flexural test on concrete can be conducted using either three point. It is a trowel applied high performance coating, applied onto noncombustible substrates as an air, vapour, and moisture barrier for durock puccs and insulrock systems.
Flexural analysis of reinforced concrete beams iit academic resource center. Flexuraltensile strength ratio in rocklike materials 221 wave velocity of the material, and the coordinates of each receiver, the event hypocenter can be estimated with a. The best way to mix high performance fast set is to use a paddle mixer on a drill. With an approximate compressive strength of 5000 psi after 28 days, usg. But thought i would ask as i am about to undertake this in the next few days. This paper is, therefore aimed at establishing an appropriate relationship between flexural strength and compressive strength from the mechanical properties of a pks concrete slab determined indirectly through the direct characterization of shear wave velocity at various mixes and watercement ratios, that is nondestructive, and thereby. Usg durock brand floor prep portfolio brochure english. Flexural strength test astmc140 masons supply company.
Portions of the mortar prisms tested in flexure according to this test method may be used for the determination of compressive strength in accordance with test method c349. Compressive and flexural strength the standard method of specifying concrete for most structural applications is by characteristic cube strength. Flexural strength the flexural strength of tile specimens after 7 and 28 days for four mixes are given in figure3. It is a measure of the maximum stress on the tension face of an unreinforced concrete beam or slab at the point of failure in bending. Flexural strength and toughness of steel fiber highstrength. Flexural test evaluates the tensile strength of concrete indirectly. Submittal data durock brand ne floor patch an easy. Special master bond one and two component epoxy systems offer outstanding flexural strength properties. Cip 16 flexural strength of concrete what is flexural strength flexural strength is an indirect measure of the tensile strength of concrete.
Durock and other concrete backerboards have no structural integrity and do not add to the structural strength of subflooring. It is a measure of an unreinforced concrete beam or slab to resist failure in bending. However, the best correlation for specific materials is obtained by laboratory tests. The deflection and cracking behavior of concrete structure depend on the flexural tensile strength of concrete. Product data submittal job name approvals contractor date. Epoxy strengths compressive tensile flexural bond epoxy. It is measured by loading 6 x 6 inch 150 x 150mm concrete beams with a span length at least three times the depth. The flexural strength of the composites varies from 81. Fencing flooring garage door installation garage door repair handyman. If your floor is the least bit springy or mushy when you walk on it, it will be necessary to do some serious shoring up before tile setting begins. Flexure test is intended to give the flexural strength of concrete in tension. Mix with water to patch and level concrete or plywood as thick as 12 mm. I would like to use 14 for this floor to try to level off with the hardwood floor outside the bath. After the occurrence of the firstcrack, the fibers effectively work, carry the entire applied load, and tend to suppress the localization of microcracks into macrocracks and consequently the flexural strength increases.
Marble and natural stones must have sufficient flexural strength for use in flooring systems. An appropriate relationship between flexural strength and. Two equations are proposed for predicting the flexural strength of high strength concrete with and without fibers. This mold resistant tile backer makes it the perfect choice for tile and flooring in baths.
Nov 10, 2017 is method of flexural strength of concrete testing, laboratory method. The subfloor system should be designed with a minimum. Could someone describe how to install durock correctly on a wood subfloor. There actually is some strength to durock btw if you search, you will see. Flexural strength and creep characteristic of tiles. The tensile bond strength of the concrete slab over which usg durock exg concrete repair patch is being applied must be a minimum of 175 psi 1. Durock brand ne floor patch is a product in the gypsum cement underlayment category. Underlayment patch and skimcoat is a portland cementbased floor patch and skimcoat. Provides a minimum compressive strength of 5000 psi after 28 days drying time.
The transverse bending test is most frequently employed, in which a specimen having either a circular or rectangular crosssection is bent. Usg durock brand advanced skim coat floor patch s a versatile calcium aluminate floor patch and skim coat for interior use over wood, concrete and gypsum subfloors and over most interior floors, including ceramic and quarry tile, terrazzo, wood, metal and interior concrete, as well as properly prepared residues of cutback and other non. On the floor, durock and tile are sufficient, so long. An added bonus to cement board use is its resistance to mold growth. Flexural strength psi 1700 750 900 750 not indicated not indicated not indicated compressive strength psi 6500 n.