It should be noted that there can be significant differences between static friction typically higher and kinetic sliding friction. The latest edition of pcas concrete masonry handbook, appendix a, gives a precast concrete to concrete masonry friction coefficient of 0. As the applied force, f, is increased from point 0 to point a, the static friction force, r e, is increased in the same module until a time when the body is about to slide. A value of zero would mean no friction at all, an elusive property. Allouche1, chris bartlett1, ang sherpa1, and brent keil2 1 trenchless technology center, dept. Friction coefficient of steel on concrete or grout. Experimental evaluation of soilpipe friction coefficients for coated steel pipes shaurav alam1, erez n. The culmination of this study is to provide subbase friction profiles for determining concrete and steel stresses due to horizontally induced movements over stabilized subbases. What value of coefficient of friction do you consider, when base plate shear is transferred through friction.
Example friction force the friction force of a 100 lb wooden crate pushed across a concrete floor with friction coefficient of 0. The nature of mobilizing friction between concrete and soil is somewhat different for clay and sand. Friction and cohesion coefficients of composite concrete. Friction coefficient of steel on concrete or grout journal. Typical coefficient of friction values for common materials. Coefficients for some common materials used in ducts and pipes are indicated below. Minimum value of coefficient of static friction, bs 5975. The coefficient of static friction, typically denoted as. One earlier study used steel plate to establish the coefficient of friction between epoxycoated and uncoated steel plates and concrete cairns and abdullah, 1994. You can find good background information on friction here. The coefficient of friction was found to be nearly constant with an average value of 0. Roughness of concrete interface will change the friction coefficient of the concrete interface. Friction coefficient between frp pultruded profiles and concrete.
The higher the value of the coefficient of friction, the less is the possibility of slipping. In your case, place a piece of concrete any size on another flat surface also made of concrete. Static and kinetic friction coefficients of scots pine. A total of 181 hydraulic tests were run on 18, 24, and 36inch circular concrete pipe and. Stabilized subbase friction study for concrete pavements. International journal of computer applications in technology, inderscience, 2009, 34 1, pp.
Cement or mastic lined iron or steel pipe 160 148 140 copper, brass, lead, tin or glass pipe or tubing 150120 140 wood stave 145110 120 110 welded or seamless steel 15080 100 cast and ductile iron 15080 100 concrete 15285 120 100 corrugated steel 60 60 mannings equation roughness coefficient n material values for n range. The specimens were composed of a concrete block and a coupon of the gfrp pultruded profile. Typically the value of u between concrete and subbase is 0. The behaviour of components in terms of resistance, stiffness, and deformation capacity is summed up for components in concrete and steel parts. The friction coefficients considered below are for static friction cases where two solid surfaces in contact with each other are resisting relative lateral motion. However, several studies assumed one of the two types of friction coefficients and evaluated the other friction coefficient kitani et al. Model coupling friction and adhesion for steel concrete interfaces.
Friction and friction coefficients engineering toolbox. Rubber in contact with other surfaces can yield friction coefficients from 1 to 2. It was found that, at dry sliding, the friction coefficient. Friction coefficient of steel on concrete or grout pdf. Coefficient of friction for steel on concrete at high normal. The coefficient of friction betwen sands such constructicn a. Experimental work the experimental work encompassed two areas. The current study represents the first to establish the coefficient using reinforcing bars. Sep 19, 2018 this paper presents the experimental results of a direct shear test to determine the friction coefficient between fibre reinforced polymer frp pultruded profiles and concrete. Experimental study of friction resistance between steel. The static and kinetic friction coefficient values reference table shown in this article will be helpful for finding the cof values of commonly used materials. For dry interface, the coefficient of static friction should be taken as 0. A short table is included above the main table to illustrate how the coefficient of friction is affected by.
Skin friction of micropiles embedded in gravelly soils abdul. That time corresponds to maximum static friction, and its value is obtained by the expression. Maximum shear resistance between concrete and sand develops at the displacement less than 2 mm. The use of highstrength frictional bolt shear connectors can greatly enhance the sustainability of infrastructure. The coefficient of friction can be easily determined by doing a simple test with the actual materials. Friction coefficient between frp pultruded profiles and. Furthermore, some relevant studies referred to the strains measured by conventional electrical resistance. A short table is included above the main table to illustrate how the coefficient of friction is affected by surface films. Sneed, and donald meinheit click here to view the full journal article. Values outside this range are rarer, but teflon, for example, can have a coefficient as low as 0. For dry interface, the coefficient of static friction. Examination of the effective coefficient of friction for shear friction design date published. These are significant variations as indicated in the following example calculation.
On the other hand, the average static friction coefficient between concrete to steel plate was identified as 0. Reinforcement steel elements compromise to about 50 percent of the pile. A frictionbased connection for retrofitting rc frames by. Cement consumption coefficients for various construction works. To provide a contribution to this area, 21 tests were. Hazenwilliams coefficients are used in the hazenwilliams equation calculate friction loss in ducts and pipes. F f wu, where f f is the frictional force, w is the weight of the slab and u is the coefficient of friction. Both graphite and teflon serve as friction reducers, compared to the plain surfaces, irrespective of the rate at which slip is initiated. Coefficient of friction for steel on concrete at high. Coefficients of cement consumption works for various construction activities involving cement mortar, concrete etc. For plain steel or cement mortar, the dynamic coefficient of friczion was greater than the static coefficient of friction by about 25 percent. It is recommended that the coefficient of static friction for concrete cast on steel plate and grout cast below steel plate should be taken as 0.
Static and kinetic friction coefficients of scots pine pinus. Typically steel on steel dry static friction coefficient 0. Friction and coefficients of friction nathan sandberg. Prefabrication of composites beam reduces the construction time and makes them easily to be assembled, deconstructed, and partially repaired. The coefficient of friction for a concrete subbase was above 2. Coefficient of friction for steel base plate to concrete bridgesmith structural 14 nov 18 17.
The expression used to calculate the force required to overcome friction is. Construction works involving cement as one of the material requires cement consumption coefficients for estimation of quantities and cost of such works. Some useful numbers on the engineering properties of materials geologic and otherwise geol 615 coefficient of sliding friction for most rocks, varies between 0. Friction coefficients of steel on concrete or grout. Static friction is friction between two or more solid objects that are not moving relative to each other. Calculating shear friction using an effective coefficient of friction pci. These companies can provide surface coating fluids containing particles to increase the coefficient of friction i.
Most dry materials in combination have friction coefficient values between 0. Friction coefficients of thermoplastics against steel. Various reference sources provide values similar to the values below. Existing works on interfacial behavior friction is one of main parameters to assess the interface shear strength and the monolithic behavior of composite concrete to concrete bond.
Therefore, it does not affect the results for normalweight concrete. What is the coefficient of friction for concrete and. Investigationoftheslidingbehaviorbetweensteelandmortar. Friction coefficients between different wheeltire materials and concrete. Experimental investigation of shear transfer in exposed. Static and kinetic friction coefficients of scots pine pinus sylvestris l. Extreme care is needed in using friction coefficients.
The second means of shear transfer is bearing against concrete of the base plate, column, andor shear lug. The little book of pavement friction virginia tech. Model coupling friction and adhesion for steel concrete interfaces michel raous, mhamed ali karray to cite this version. The level of uncertainty of the information below is indicated by using steel on steel as an example. When a metal surface is perfectly clean in a vacuum, the friction is much higher than the normal accepted value and seizure can easily occur. A 2003 report by the society for protective coatings states that flooring with a high static coefficient of friction scof, 0. Experiments were performed to determine the coefficient of friction between concrete and steel. Model coupling friction and adhesion for steel concrete.
The displacement between concrete and normally consolidated clay which produce the full friction resistance is about 4 mm. Values are not included in design codes such as bs 8110 now withdrawn and eurocode 2. The coefficient of friction cof, often symbolized by the greek letter, is a dimensionless scalar value which describes the ratio of the force of friction between two bodies and the force pressing them together. To evaluate the skin friction of micropiles embedded in gravelly soils, a numerical model was. There may be a requirement to know the coefficient of friction between elements in contact, for example precast units resting on a concrete corbel or structural steel members on a concrete support. The frp pultruded profile used in this study was glass fibre reinforced polymer gfrp isection. Concrete 15285 120 100 corrugated steel 60 60 mannings equation roughness coefficient n material values for n range typical design value polyethylene pipe 0. Frictional characteristics of roadside grass types cenek, p. Coefficient of friction equation and table chart engineers edge. The first means is friction between the steel base plate and the mortar or concrete surface on which it rests.
After sliding had occurred between steel and a soil with a high clay fraction, however, the residual coefficient of friction at the applied displacement of 15 mm was much smaller than the maximum coefficient of friction. Pcis design handbook says the concrete to concrete friction factor for dry conditions is 0. For concrete specimens, the interface between con crete and steel. However, researches about the concrete steel friction behavior are very limited. The major sources of friction are roughness interaction, adhesion and plowing 10,11. This paper presents the experimental results of a direct shear test to determine the friction coefficient between fibre reinforced polymer frp pultruded profiles and concrete. Effect of grout properties on shear strength of column base. The little book of tire pavement friction version 1. The friction coefficient of rubber sliding against polymeric indoor flooring materials of different surface roughness was investigated, 1. Values for the coefficient of friction are not included in design codes.
Based on the experimental investigations by rabbat and russell, the friction coefficient between the steel plate and the grout is considered as. Kutter coefficient manning coefficient concrete clay metal concrete clay metal 12 18 24 30 0. Slip and fall protection and friction on concrete floors. Here is an excellent discussion on friction coefficients, plus a comprehensive table of friction coefficients. For example, static friction can prevent an object from sliding down a sloped surface.
The rccm model is extended here for describing the steel. Column bases in shear and normal force heron homepage. The test results show that the initial static friction coefficient for steel and. Friction coefficient of steel on concrete or grout asce library. There may be a requirement to know the coefficient of friction between materials in contact, for example precast units resting on a concrete corbel or structural steel members on a concrete support. Investigation of the sliding behavior between steel and. Coefficient of friction for steel base plate to concrete. For conventional shoes, a concrete floorsurface will yield a coefficient that is high enough about 0. The coefficient of friction depends on the materials used. Pdf the frictional feature has an important role in engineering field. If the applied force, f, remains equal to r e max, point b. A 100 lb wooden crate is pushed across a concrete floor. The coefficient of friction cof measurement provided in this standard is an evaluation of a tile surface under known conditions using a standardized sensor material prepared according to a specific protocol.