Step 1 Step 2 Step 3 Step 4 Sample Riffling:- the process of obtaining a small representative quantity of sample by dividing a large quantity of material using a riffle box or sample splitter containing alternating slots , which divide the material into two equal parts. Then, one of the obtained two parts is poured again into the slots until the desired quantity is obtained. Test procedure: a Dry Sieving: 1 Obtain a test sample by quartering or riffling the material.
Grading Sieves 6 Weigh either individually or cumulatively the material retained on each sieve m2. Note: Cumulative weights provide the percentage of particles retained on the sieves progressively, while individual weights provide the percentage retained on an individual sieve does not follow the sieve sequence. The indices obtained in both tests reveal the dimensions of aggregate particles, as some particles are normally cubic while others are flaky or elongated.
The test is carried out on the aggregate particles of different sizes from 6. Flaky particles Test procedure: 1 Obtain the test sample by quartering or riffling the aggregate. Retained Wt. Passing fraction fraction on the gauge on the gauge mm g g g 63 - 50 It is carried out on the coarse particles from 6.
Test procedure: 1 Obtain the test sample by quartering or riffling the aggregate. Passing on fraction fraction on the gauge the gauge mm g g g 50 - Aggregate Crushing Value ACV Some aggregate particles resist crushing while some crush during rolling due to the effect of weathering process or micro-fractures developed by blasting or crushing operations. Crushing of aggregates during construction process affects the grading, density and strength of a mix or layer made with such aggregate.
To measure resistance of aggregate to crushing, the ACV test is carried out on the 14 — 10mm aggregate fraction, by applying a KN force gradually over a period of 10 minutes. Test procedure: 1 Obtain the required fraction by sieving the aggregate on 14mm and 10mm sieves. Rock fissures 2 Take the fraction passing 14mm but retaining on 10mm sieve and dry it in oven for about 4 hours before testing. Retained on 2. Passing 2. It is also conducted on the 14 — 10mm fraction as for the ACV test, however, the TFV is preferred for weak aggregates in order to overcome the cushioning effect of excessive fines that might be produced by the ACV test.
The test is carried out on a dry or soaked aggregate sample. Test procedure: 1 Sieve the aggregate on 14mm and 10mm sieves as for the ACV. Compression Machine 2 Plot the results on a chart with forces on x-axis and the percentage passing 2.
It is commonly carried out on the 14 — 10mm fraction; however, 20 — 14mm or 10 — 6. The chosen fraction can be tested in a dry condition or soaked condition. Test procedure: 1 Obtain the required fraction by sieving aggregate on the specified sieves e. Retained on the sieve m2 Passing separation sieve p The applicable aggregate fractions are: Group A: Mix Group B: Mix 19 — Group C: Mix 9.
Group D: Take 4. LAA Machine 2 Obtain about g from each group i. Calculations: Material passing 1. Sulphate Soundness SS Sulphate soundness test measures the effect of salts on aggregate particles.
The effect is measured as the loss in aggregate weight after repetitive drying and soaking the aggregate in Sodium or Magnesium sulphate solution. The applicable sulphate solution is prepared as follows; Sodium sulphate solution: is made up of g of Sodium sulphate and 1 litre of water is supposed to have a specific gravity of 1. Magnesium sulphate solution: is made up of g of Magnesium sulphate and 1 litre of water is supposed to have a specific Sound aggregate gravity of 1.
Test procedure: 1 Obtain the sample by quartering or riffling a large quantity of aggregate. Repeat soaking and drying five times cycles.
Unsound aggregate 11 After the 5th cycle of soaking and drying , allow the samples to cool and wash them thoroughly with warm water at 45 0 C. Organic Impurities Presence of organic impurities in aggregates especially natural sand affects the setting time and hardening of concrete and may also cause deterioration of concrete or pop-outs. To test the organic impurities in fine aggregate, the following stuff is used: Test reagent: a solution made up of 3-parts Sodium hydroxide NaOH and parts water.
Standard solution: a solution made up of 0. It is used as a reference colour for classifying the sample solution after adding the reagent.
Colour plate: a small plastic plate with different colour slots, used to Sodium hydroxide classify the colour of sample solution as a substitute for the standard solution. Test procedure: 1 Obtain a test sample of about g by quartering or riffling a large quantity of fine aggregate sand. Lime 6 Allow the sample to stand undisturbed for 24 hours and compare the colour of the sample solution with the colours on the colour plate or with the standard solution. Clay lumps and friable particles Clay lumps are small soil balls, which visually look-like gravel or aggregate particles, but soften and dissolve in water or liquids.
Friable particles are granular particles which lose bond and break up crumble in water or liquids. Presence of the dissolving or crumbling particles in an aggregate group affects density, strength and durability of a mix made with the aggregate. As such weak particles crumble during rolling or disintegrate due to moisture; they leave pockets and form weak planes in a concrete structure or pavement layer.
To test such defective particles, the aggregate fractions are soaked in water and squeezed by fingers to dissolve or break up the lumps Typical friable particles and friable particles. Test procedure: 1 Divide aggregate by quartering or riffling to obtain test sample. Material finer than 0. On the other hand, such finer materials increase water demand for a concrete mix, resulting into a low strength concrete. To test presence of such deleterious materials, aggregate fraction is immersed in water to disperse the finer materials and decanted on the 0.
Then, the loss in weight obtained after decantation is counted as the amount of materials finer than 0. The applicable terms in the test include the following; Decantation: removal of suspended materials by tilting a container Variety of aggregate particles gently without disturbing the settled particles. Suspensoid: a solution of very fine particles dispersed throughout a liquid. Test procedure: 1 Divide aggregate by riffling or quartering to obtain the sample.
Repeat this step until water is free of suspensoid. Calculations: Material finer than 0. Lightweight pieces Presence of porous and light pieces e. To measure the presence of suchlike pieces, aggregate particles are immersed in a heavy liquid with higher specific gravity than water and floating materials decanted and weighed as the lightweight pieces. Heavy liquid may be made by dissolving the following compounds in water: o Zinc Chloride for SG less than 2. Recommended weight of sample Test procedure: for Coal and lignite test: 1 Divide the aggregate to obtain the representative test sample.
Acid-soluble materials Presence of acid-soluble materials in the aggregate mass may affect durability of the aggregates and structures exposed to a chemical environment.
In testing the acid-soluble materials, aggregate particles are soaked in diluted hydrochloric acid solution and percentage loss in aggregate weight is calculated and reported as the quantity of acid-soluble materials. Test procedure: 1 Dilute ml of concentrated hydrochloric acid with relative density of 1. Specific gravity SG Specific gravity is the ratio of density of a solid particle to the density of distilled water. In addition, the test measures impermeability of aggregate particles water absorption.
It is a useful data for computing the volume of aggregate and voids in different mixes especially concrete and asphalt. Generally, the three parameters given by the test are: Bulk specific gravity:- the density of permeable particle including permeable and impermeable voids normal to the particle. Apparent specific gravity:- the density of impermeable portion of particle excluding permeable and impermeable voids normal to the particle. Water absorption:- the amount of water absorbed by solid particle expressed as percentage of dry mass of the particle.
Glass Pycnometer Test procedure: a Fine aggregate passing 4. Cone and Tamping rod 9 Add more water and shake pycnometer to remove air bubbles. Sand equivalent SE Sand equivalent test determines the proportion of plastic clays, silts or amount of dust in fine aggregates for concrete.
To conduct the test, a working solution of Calcium chloride is used to disperse clay and dust into suspension; and the height of sand column sand reading is measured and compared to the height of suspension clay reading. The test includes the following terms; Working solution:- is made up of 22ml of stock Calcium chloride solution to 1 litre of water. Sand reading:- top level of sand column. Sand Equivalent test set Clay reading:- top level of clay suspension. Test procedure: 1 Fill a graduated cylinder with ml of working solution.
Sand Reading h2 7 Then, twist the irrigator in the material to flash the fine materials into suspension until the cylinder is filled to the calibration mark. Cement According to BS 12, cement is hydraulic binder finely ground inorganic material , which when mixed with water forms a paste that sets and hardens by means of hydration reactions and processes; and which after hardening retains its strength and stability even under water. Clinker is again ground down into a finer powder smaller than 0.
When mixed with water, cement forms a paste that sets and hardens by means of hydration process chemical reaction between cement compounds and water molecules, which generate heat known as heat of hydration. Evaluations of cement properties require sophisticated laboratory equipment and skills.
However, since cement is manufactured under controlled process, most of the tests are conducted at the factory laboratory and supplied with cement batches as quality V1 document certificate of quality. Therefore, very few tests are normally conducted at the site laboratory. Test Procedure: 1 Fill a small-calibrated measuring cylinder with reasonable volume of kerosene V1. Test Procedure: 1 Mix g of cement with a measured quantity of water to produce a plastic mouldable paste.
Record that percentage as the moisture content for normal consistency. Aggregate Aggregate is used in concrete to expand the mix volume, to control shrinkage properties and to contribute strength. As a result, quality of aggregate has great influence on the strength, workability, permeability and durability of concrete mixes.
Concrete aggregate should be clean and strong enough to resist forces and exposure conditions. The particles should be hard, dense and free from excess dust. Soft aggregates e. Therefore, careful selection of rock source is very Crushed Aggregate important, as quality of aggregates depends on the geological composition of the rock. However some researchers recommend the use of marine aggregates for concrete after washing with clean water due to concentration of salts sulphate and chloride , the suitability of such material should be carefully investigated and proved by laboratory testing if washing has significantly reduced the injurious substances to an acceptable amount.
Table 4. Smooth and rounded particles produce better workability but develop weak internal friction and poor bond with cement paste. Flaky and elongated particles produce poor workability and particle interlock.
Therefore, aggregate particles should be cubic, rough and well graded from fine to coarse to enable workability, proper bond Coral Aggregate soft and adequate density. Water Water to be used for concrete should be clean and free from aggressive compounds such as; oil, acid, alkali, salt, sugar, organic matter and other compounds that may attack concrete components.
Such injurious substances may affect the setting time, strength, bond and shrinkage of concrete; or may cause corrosion of reinforcements. Generally, drinking water is the mostly recommended water for concrete production and curing. Sources like river, lake or boreholes may be used if tested and proved to be suitable for concrete production. However, the use of seawater for mixing and curing concrete is still contradicting due to presence of salts sodium chloride, magnesium sulphate and potassium.
On the other hand, some standards e. Indian Standard IS of permit the use of seawater for mixing and curing mass concrete where such use is unavoidable. Some of the aggressive compounds in water and their degree of attack are shown in table 4.
Reinforcements Generally, reinforcements are steel bars, plastic or glass fibers incorporated in concrete to provide tensile strength. Concrete is not elastic material, therefore, it cracks and breaks suddenly when stretched pulled apart by the imposed loads. However development of technology has led to the application of Plain bar glass and plastic fibres in concrete as reinforcements, steel bars are still the most applicable material for reinforcing the loaded concrete members.
Steel is very strong in both tension and compression; therefore, its use in concrete prevents concrete member from stretching. Additionally, the use of reinforcement helps to hold the cracked portions together and allows the Ribbed bar concrete structures to be moulded in a desired shape without fear of failure. Steel fibres b Reinforced concrete Tension Steel bars prevent stretching and cracking of the bottom side when the upper side is loaded.
Plastic fibres Figure 2: Tension in a concrete member with end support. Un-reinforced concrete structure b Reinforced concrete Steel bars prevent stretching and cracking of the upper side when the arm tends to bend downward.
Figure 3: Tension in a concrete member with one end support. While some bars are made plain smooth some are ribbed to improve bond with concrete, however, their general performance Reinforced concrete structure depends on the following factors; o Type or grade of steel.
Admixtures Mineral and chemical admixtures or additives are powdery or liquid compounds added to fresh concrete to make it work or behave as desired. Mineral admixtures such as fly ash, which is by-product of coal combustion, blast furnace slag by-product of steel production or silica fume by-product of silicon and ferrosilicon alloys are normally added to concrete as cement extenders.
Chemical admixtures are added to a fresh concrete mix to modify its workability, setting time, colour or other physical properties. They make concrete more plastic, hence, self-leveling or easy to consolidate and achieve high density.
They increase strength of concrete by reducing water demand. The mechanism of plasticizing is not chemical but physical effect of particle dispersion. Concrete mix a Mix components: Concrete is basically made from cement, aggregate and water. Other components e. Fresh Concrete mix Aggregate Mix extender and Strength contributor.
Water Lubricant and hydration facilitator. Admixtures Property modifier. Reinforcement Internal support provides tensile strength b Types of mixes: Concrete mixes are normally grouped as mass concrete and structural concrete, depending on the mix applications; o Mass concrete:- a plain mix without reinforcement.
Used for blinding ground surface before application of structural concrete. Used to cast members which bear tensile stress. However, fresh mixes also could be grouped into three categories; o Dry or stiff mix:- a mix without slump.
Such mix requires application of rollers e. Reinforced Concrete o Plastic mix:- a mix with slump up to mm.
Used where the application of tamping equipment or vibrators is possible. Such mix is normally poured by concrete pump or tremie pipe in narrow members e. However there is a graphical method of carrying out a mix design as provided in TRRL and Road Note 4 , the volumetric ratios, such as cement :sand :aggregate for mass concrete and for structural concrete is still popular in Tanzania, since the graphical method is somehow complicated for beginners, so is not regularly used in many construction sites.
Therefore, most of the material engineers normally make several trials batched in variable ratios and adjust cement content to arrive at the specified class of concrete. That may consume time, as target strength is achieved Laboratory Mixer after 28 days. To get a good mix by this method, the specific gravity of each material should be tested and used with the weights to alter the mix volume into a cubic meter 1m3.
Water Total Mixing ratios 1 2 3 0. Concrete Paver 2 Proper mixing is done by using small mixers; however, hand mixing also can produce homogeneous mix if carried out thoroughly on a non-absorbent surface.
Therefore, adjustment should be done carefully, as increase of sand and water lowers the strength of concrete. Such mix should contain a balanced proportion of cement, sand, coarse aggregate and water. Mixes rich in cement are much stronger; however, they are more expensive and prone to shrinkage and thermal cracks caused by heat of hydration.
Workability and Strength Workability means simplicity of movement or placement of a concrete mix. Fresh concrete should be self-leveling or should pack properly when tamped or vibrated by mechanical tools. Apart from the vast methods of checking the workability of concrete, the most applicable methods are slump test for plastic mixes , flow test for flowing mixes and V-B time for stiff mixes. However, the tests of particular interest are the slump and flow tests.
The test is suitable for plastic concrete mixes slump less than mm and is conducted within 5 minutes of sampling. Test procedure: 1 Place base plate on a flat surface and hold the cone firmly on it. Mixes of such a high slump are self- leveling and are normally made and poured by concrete pumps, or cast in a confined structure e. The test uses a truncated cone as the slump cone , with mm diameter at the bottom, mm at the top and mm high.
The cone is used on a hinged table of xmm. The slump test is accomplished on the table, then, one side of the table is lifted up 40mm and allowed to drop freely; and the Flow Cone and Table diameter of the area covered with concrete measured in mm and reported as the flow value. Figure 5: Flow table and cone Test procedure: 1 Wipe inside of the cone and the table with a damp cloth. Directions of Flow measurement 6 Hold the cone firmly on the table and clean excess material around it.
The cubes are made as follows: Procedure: 1 Place the moulds on a flat surface under shed. Compacting a concrete cube 3 Smooth the surface with trowel or steel float. The cylinders are made as follows: Procedure: 1 Place the cylindrical moulds on a flat surface under shed. Therefore, the most common tests for judging the strength of concrete are Compressive test and Tensile splitting test. Quality and Durability The quality of concrete is simply indicated by strength and workmanship.
Strength is tested in the laboratory on cubes or cylinders made from the mix ; while workmanship is assessed visually during production. However, the main factors that guarantee quality are: 1 Suitability of materials: Suitable cement provides adequate strength and resists ground salts. Hard and strong aggregates reduce the risk of wear and Good Workmanship permeability, while suitable water facilitates hydration process without attack to other mix components.
The proper amount of water required for hydration reaction is equivalent to of the weight of cement i. Therefore, additional water is normally added to concrete mixes just for workability purposes.
As concrete sets; extra water normally evaporates and leaves tiny voids that form planes of weakness in the concrete. So, the more water in the fresh concrete mix the more voids in the hardened concrete.
Slanting the vibrator, as well as over- compacting or tamping bring more paste on top and push the aggregate to the bottom, hence causing mix segregation. Poor Workmanship 5 Curing: Favourable temperature and subsequent curing the concrete with specific compounds or covering with hessian cloth and spraying water prevent rapid loss of water and facilitate hydration process, resulting in proper strength development.
Apart from quality and workmanship, other factors that may affect durability of concrete are; 1 Permeability: Porous concrete allows ingress of liquids and poses the reinforcements to corrosion or the aggregates to salt attack.
Nevertheless, it may allow growth of vegetation; hence, causing Proper formwork improves cracks and stains on concrete. Workmanship 2 Wearing forces: Dynamic forces, like running water or mechanical abrasions wear down the concrete gradually. Fire also causes excessive expansion to concrete materials e.
However, this climatic phenomenon is not common in the tropical zone of east Africa. It is very important to know behaviour of soil as it is used largely for the construction of embankments and pavement layers, such as roadbed, fill, improved sub-grade, sub-base, base and wearing course for gravel roads. Spreading Soil materials Figure 6: Typical cross-section of a road Consistency of soil varies considerably with location and profile depth due to weathering process and transportation modes.
Moreover, some functional properties such as grading, plasticity, permeability, compressibility and bearing capacity also vary with soil types. Soil is very sensitive to moisture content than any other road construction material. Therefore, most of the road failures are more often subjective to its behaviour, which for the most part is affected by the Atterberg limits liquid limit, plastic limit and plasticity index , grading particle size distribution , density Dumping Gravel materials compactness and strength bearing capacity.
Grading Grading test also known as Sieve analysis or Particle size distribution determines the proportion of particle sizes in a granular material e. The test is conducted in the same way as outlined for aggregates. However, since most of the soils are cohesive the particles bind among themselves , wet sieving is more accurate method for determining the grading of soil than dry sieving. Test procedure: 1 Break lumps in the dry soil with mallet without crushing particles. Grading Sieves 3 Determine the weight of test sample and record it m1.
Note: Since, the smallest size of sieves used in laboratory is 0. Dispersant: - is made up of 33g of Sodium Hexametaphosphate, 7g of Sodium Carbonate and distilled water to make 1 liter of solution.
Dispersion: - means separation of disconnected particles into suspension. Sieve Shaker Grading by sedimentation method is not common in roadworks, therefore, is not outlined in this Guide. However, the useful formular for calculating the equivalent particle diameter has been provided for awareness of the reader.
Retained on the siev e x Atterberg limits Atterberg limits are simply referred to as plasticity property, since; the outward sign of the limits is plasticity index, which reflects the sticking property of soil linked with clay content. However, the Atterberg limits determine general consistency of soil i.
The limits were established by a Swedish chemist know as Albert Atterberg, hence, taking the name Atterberg. It is determined in the laboratory as the moisture content, which allows a soil sample to be moulded into a loop that cracks when its diameter is about 3mm.
Test procedure: 1 Sieve the air-dried soil on 0. It is determined in the laboratory as the moisture content that makes a soil groove close with 25 blows of the Casagrande apparatus; or the moisture content that allows a cone to penetrate 20mm in a soil sample in 5 seconds. Casagrande method: 1 Take about g of material passing through 0. Casagrande Apparatus 5 Turn the handle at a rate of 2 revolutions per second until the two sides of the groove come into contact along a length of 13mm and record the number of blows that closed the groove.
Penetrometer method: 1 Sieve air-dried soil on 0. It is determined Linear Shrinkage Mould arithmetically as the difference of Liquid limit and Plastic limit i. It simulates the volumetric changes that occur as wet soil dries. Test procedure: 1 Clean the mould, measure the length h1 and apply a thin film of grease at the inside walls. A Digital Balance 2 Take about g of the soil paste at Liquid limit, fill it fully in the mould and tap it on a hard surface to remove air pockets. BS , Part 2.
P1 P6 wt. Y3 Y4 wt. Proctor Proctor is a compaction method, used in the laboratory to show the relationship of moisture content and density of a material compacted mass of material in a unit volume through a range of moisture contents. It was named after R. Proctor who developed the relationship. Kayode Alao. A short summary of this paper. Download Download PDF. Translate PDF. Design and Construction of Concrete Roads O. O Alao Department of Civil Engineering, University of Cape Town, Cape Town, South Africa ABSTRACT This paper reviews current trends in the design and construction of concrete roads, the common types of concrete pavements, the failure modes of rigid pavements, the design method used in South Africa and construction site practices that designers and contractors carefully consider in order to ensure concrete pavements meet their strength, durability performance requirements with respect to sustainability and desired service life.
It is also shown that durable concrete pavements do not depend solely on the concrete quality but also on proper site construction practices which include placement, compaction and curing.
Therefore, it is important for pavement engineers to understand and address the issues of appropriate materials selection, mix design and detailing, prevailing drainage conditions, construction techniques, and pavement performance.
Likewise understanding the theoretical background underlying commonly used design procedures, and to know the limitations of the applicability of the procedures are important. Keywords: Concrete roads, rigid pavement lower in homogenous materials. Higher flexural 1. Economically, they are makes it deform at higher stress. Concrete pavements often the most favourable option to flexible pavements distribute stress over a large area; therefore base layers when life cycle costs are taken into account.
This is due undergo less pressure from axle loading as shown in to the fact that concrete requires minimal maintenance figure 1 below. Concrete pavements have been used for local roads, streets, highways, airport runways, parking areas, industrial structures, and other types of infrastructure.
With decades of construction and use of rigid pavements, it has become clear that in comparison to flexible pavements asphalt-paved , sustainability of the environment is favourably impacted by their longer service life.
Concrete surfaces also have a higher Figure 1: Load transfer mechanism reflectiveness off its surface, this allows for improved visibility at night and reduced lighting on the road Rens, We may also take note of the reduction in traffic 2. PAVEMENT TYPES delays caused by concrete pavement construction which can be reopened even after a couple of hours as opposed There are four major common types of pavements to flexible pavements construction, which in turn cuts namely; back on fuel consumption and exhaust gas emissions.
However, a survey carried out by the American Precast concrete pavement systems are systems Concrete Pavement Association indicated that this that are essentially fabricated or assembled off- method is no longer popular for concrete pavement site, transported to the project site and installed on construction in the US as the new American Association a prepared foundation existing pavement or re- of State Highway and Transportation Officials AASHTO graded foundation — see Figure 2.
Use of precast concrete pavement technologies must result in reduced lane closures or better managed lane closures that in turn result in less traffic disruptions and improved safety at construction zones. The precast concrete pavement technology is equally applicable to repair and rehabilitation of rural roadways where use of conventional may not be feasible because of ready access to the conventional techniques or cost Shiraz, Figure 3: Joint reinforced concrete pavement 2.
They are equipped with longitudinal steel reinforcement see figure 5. The diameter of the reinforcing bars is calculated in such a way that cracking can be controlled and that the cracks are uniformly distributed with spacing of between 1 — 3 m. The crack width has to remain very small, i. An example of continually reinforced concrete pavement is the route Figure 2: Placing precast segments on for the bus rapid transit BRT in Cape Town.
The polyethene FHWA, construction method for this concrete road system doesn't have any joints in it, except at intersections 2. A large scale of the implementation of 2. JPCP is the most prevalently constructed type of concrete pavement because it is the cheapest. It is cheap because there is no need for any reinforcing steel. Reinforcement is used in concrete roads not for load carrying for mainly Figure 4: Ultra-thin RC pavement in Tshwane, Pretoria as a crack arrester or control.
The dowels are spaced adopted from www. Figure 5: CRCP adopted from www. It is a low to no slump mixture that is closer in some respects to cement treated The manual also lists the following failure modes occur aggregate base than a conventional flowing concrete in CRCP: Delatte, The material is breaks. The pavement may be allowed to crack naturally, of punchouts, transverse construction joint or joints may be cut. Because RCC shrinks less than deterioration, and longitudinal joint seal damage.
Furthermore, risk of failure in a rigid pavement is RCC is a pavement construction solution for local streets the probability of load exceeding the bearing capacity of and roads. It is recommended for urban areas as it pavement. When constructing an RCC pavement, the key factors to consider for high quality constructions are mix design, 4.
Niethelath et al. The main reducing pavement noise, but did not address the output variables are the areas of the road that has structural aspects of producing a durable mainline shattered, has pumping, has faulting in excess of 5 mm highway pavement. The solution would most likely be a and, in case of continuously reinforced concrete, also the conventional concrete pavement structure with a crack spacing. Procedures for design and Load is expressed in terms of expected heavy-vehicle construction of pervious concrete pavements have HV axles in a given period.
The HV axle loads follow a recently been published by ACI Committee frequency distribution that is indicated by the user. ACI Committee , Information about pervious Bearing capacity of pavement is the number of HV axles concrete has been made available by the Southeast that are distributed under which the pavement becomes Cement Promotion Association on the web at unserviceable.
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