EXPERIMENT NO AIM :- To perform water absorption test on given aggregate sample by oven d rying method. APPARATUS :Measurin g weights , aggregates immersed in water for 24 hrs , oven . FORMULA :Water absorption in % = [ ( W1- W3 ) / ( W2- W1 ) ] x 100 Where Weight of empty container Weight of soaked aggregate + Weight of container = W1 = _____ Gm = W2 = _____ Gm Weight of oven dried aggregate + Weight of container = W3 = _____ Gm FIGURE :THEORY :Stones having higher water absorption values are porous and hence weak . They are generally suitable unless found acceptable based on crushing and grinding . The sample is weighted on water and the buoyant weight is found . The aggregate is taken out and weighted after th e surface is dried . The specific gravity can be calculated by diving dry weight of aggregate by weight of equal volume of water. The water absorption is expressed as percentage water absorption in terms of oven dried weight of aggregate . The specific gravity of rock varies fro m 2.6 to 2.9 . Rock specimen having more than 0.6 percent of water absorption are considered unsatisfactory values found acceptable based upon strength tests . However slightly higher value of porosity may be acceptable for aggregate used in bitumen pavement construction of the aggregate are otherwise suitable PROCEDURE :1)About 2 Kg of dry aggregate sample is placed in wire basket and immersed in water for 24 Hrs. 2) The weight of the sample is taken . 3)The aggregate sample is placed in oven ( 100 – 110 0 C ) for 24 Hrs. 4)After complete drying dry weight of the sample is taken . 5)Percentage of water absorption is calculated . OBSERVATION :- Weight of empty container = W1 = _____ Gm Weight of soaked aggregate + Weight of container = W2 = _____ Gm Weight of oven dried aggregate + Weight of container = W3 = _____ Gm CALCULATION :- Water absorption in % = [ ( W1- W3 ) / ( W2- W1 ) ] x 100 RESULT :Percentage of water absorption for a given sample of aggregate is found to be _________ %. PRECAUTION :1) The aggregate must be immersed properly in water for 24 Hrs . 2)The water from surface of aggregate must be dried . 3)Weight the aggregate carefully in spring balan ce. DISCUSSION :Rock specimen having more than 0.6 % water absorption values are considered unsatisfactory unless found acceptable based on strength test . However slightly higher value of porosity may be acceptable for aggregate used in bituminous pavement construction if aggregate is found otherwise suitable. EXPERIMENT NO AIM :- To determine flakiness index of aggregate . APPARATUS :Aggregate, set of sieves, tray, weight box etc. FORMULA :flakiness index = [ w/ W ] X 100 w = Weight of aggregateWhere, passing W = Weight of aggregate retained FIGURE :THEORY :The principal shape of Aggregate mass is determine by the percentage of flaky and elon gated particles contained in it and by its angularity . The evaluation of shape of particles made of flakiness index and elongated index and angularity numbers . The flakiness index of aggregate is the per centage by weight of aggregate particles whose least dimensional thickness is less than 0.6 times their mean dimension. The test is applicable to size larger than 6.3 mm standard thickness is used to guage the thickness of sample . PROCEDURE :1) The sample of aggregate to b e tested is sieved through a set of sieves and separated into a specified size ranges. 2) Now to separate the flaky material , the aggregate which pass through the appropriate elongated slot of thickness guage are found .The width of the appropriate slot would be 0.6 of the average of the sieve size range. 3) The flaky material passing the appropriate slot from each size range of test aggregate are added up and let the weight be W1. 4) If the total weight of sample take from different size range is w, the flakiness index is given by Flakiness Index = [ W1 / W ] X 100 OBSERVATION TABLE :- Sr No Sieve No. (mm) Weight Retained W(Gm) Weight of Aggregate passing appropriate slot (gm) W (gm) F. I. = [ w / X 100 W] 1 2 3 4 5 6 CALCULATION :flakiness index = [ w/ W ] X 100 RESULT :The Flakiness Index of a given aggregate sample is found to be _______ %. DISCUSSION :Elongated aggregate are less workable , they are also likely to break under smaller load s than the aggregate which are spherical or cubical , flakiness index values in excess of 15 % are generally consider undesirable . If is desirable that flakiness index of aggregate used in road construction is less than 15 % and normally does not exceed 25 %. APPLICATION :If the flakiness index is more than the aggregate can take less loads and are liable to fail under less load . So it is not desirable to use aggregate of higher flakiness index is permanent . EXPERIMENT NO AIM:- To determine specific gravity of a given aggregate sample by Pycnometer Pycnometer balance, Weight –box, aggregate APPARATUS:- FORMULA:- Specific gravity = (W2-W1) – (W3-W4) (W2-W1 ) Where Weight of empty Pycnometer = W1 gms Weight of Pycnometer + aggregate = W2 gms Weight of Pycnometer + aggregate +Water = W3 gms Weight of Pycnometer + Water = W4 gms Weight of aggregate = (W2-W1) gm. Weight of equal volume of distilled water = (W2-W1) – (W3-W4) gms FIGURE :THEORY :Specific gravity is the ratio of the weight of given volume of dry aggregate to the weight of equal volume of distilled water. Let (i) Weight of empty Pycnometer = W1 gms (ii) Weight of Pycnometer + aggregate = W2gms (iii)Weight of Pycnometer + aggregate +Water = W3 gms (iv)Weight of Pycnometer + Water = W4 gms Weight of aggregate = (W2-W1) gm. Weight of equal volume of distilled water = (W2-W1) – (W3-W4) gms (W2-W1 ) Specific gravity = (W2-W1) – (W3-W4) PROCEDURE:(1)Make the Pycnometer dry &Weight it with its cap &rin g (2)Unscrew the cap &Rut 200 gms of aggregate &Weight it (3)Add water to the top of brass cap. Remove all the trapped dir by pouring additional water (4)Dry the Pycnometer & fell it to the top with & weight it (5)Repeat the Pro cedure (6)Find the average specific gravity by using formula OBSERVATION TABLE :SR No Weight of Weight of aggregates empty pycnometer (W1)gm Weight of pycnometer +aggregate (W2) gm Weight of pycnometer +water +aggrate (W3) gm Weight of Pycnometer +water Specific gravity (W4) gm 1 2 3 4 Average specific gravity = SAMPLE CALCULATION:- (W2-W1) Specific gravity = (W2-W1) – (W3-W4) G = RESULT:Average specific gravity is found to be ___________ PRECAUTIONS:(1) Take the weight carefully. (2) Pycnometer must be dry for use. (3) There should be no air bubble inside the bottle. DISCUSSIONS:The value of specific gravity of aggregate is required for concrete mix design and useful for calculating water content. Stone having higher water absorptions values are porous and this weaker specific gravity also indicates strong specimen. EXPERIMENT NO AIM: - To determine the Flash &Fire point for the sample of bitumen taken. APPARATUS: Flash point set up, thermometer, heating arrangement etc. FIGURE:THEORY: This test gives up the indications of the critical temperatur e at which the suitable precautions should be taken while heating bitumen . Flash Point:-The temperature at which the volatile material i.e. bitumen emits vapours and it catches fire momentarily in the form of flash. Fire Point :-The temperature at which the volatile nature i.e. bitumen emits vapours get ignited and burns PROCEDURE: The material is filled up to the mark of filling in the cup liquid is placed too dose to the cup .All accessories including thermometers are fixed .The sample is heated at rate of 50to60 0C/min. The first flash as applied at test 170 C below actual flash point. The flash point as taken as the temperature reading on the thermometer at the time of applications of flame that causes bright flash in the interior of cup. The heating is continuous till the material’s ignited. This gives the fire point. RESULT: - = i) Flash Point ii) Fire Point = DISCUSSION:The bitumen material leaves out volatile at high temperature depending up on their grades. These volatile catch fire causing a flash. This condition is very hazardous. PRECAUTION: If the candle is used as a flame then it should be seen that flame should not fall in the bitumen, otherwise it would give flame at less Temperature as wax will catch fir e. APPLICATION: Bitumen is used in construction of pavements so the flash & fire point is determined to check for the amount of heating to avoid any accidents. EXPERIMENT NO AIM:- To Determine the impact value of a given a aggregate sample APPARTAUS:Impact testing machine, aggregates, sieves, weight box, weighing balance FORMULA:Impact Value = W3 / (W2 – W1) X100 Where, W1 = empty wt of cylinder. W2= wt of Cylinder + aggregate. W3= wt of fines passing through 2.25 mm sieve FIGURE :- THEORY: A test designed for to evaluate the toughness of stone or the resistance of aggregate to fracture under repeated impact is called impact test. The aggregate impact value indicates relative measur es of resistance of aggregate to impact, which has different effect then the resistance to gradually incr easing compression stress. The aggregate impact testing machine consists of a metal case and a cylindrical cap of internal dia of 10.2 cm and a depth of 5 cm in which the aggregate specimen is placed A hammer of weight 13.5 to 14 kg having a free fall from height 38 cm is arran ged to drop through a vertical height. PROCEDURE: (1)Aggregate specimen passing throu gh 12mm sieve retained on 10mm sieve is filled in the cylinder in 3 layers by tampin g each other or each layer by 25 flows and then measures it. (2)The sample is transferred from balance to cap of the aggregate impacttesting machin e. The metal hammer is raised to a height of 38cm.Above th e upper surface of the aggregate in the cap and is allowed to fall freely on the cap specimen After subjected to15blows of metal hammer, the crashed aggregate is sieved from 2.36 mm sieve and the sieved weight is noted. OBSERVATION:(1)Weight of empty mould = W1 = (2)Weight of mould + aggregate = W2 = (3)Weight of tines passing through = W3 = CALCULATION:Impact Value = W3 / (W2 – W1) X100 RESULT: The impact value of given sample of aggregate found out to be __________. PRECAUTIONS:(1)The aggregate used should be of good quality. (2)Hammer should be p roperly handed otherwise it may cause physical damage or injury. DISCUSSION:The impact value indicates the relative measurement of resistance of aggregate to impact, which has a different effect then th e r istance to gr adually increased compressive stress. The value less then 10 % to 20 % is satisfactory for wads. The aggregates should not have impact value more then 30 % & if it is used to say to be weaker for base course the value should not exceed 40% EXPERIMENT NO AIM:- To Determine California Bearing ratio [CBR] value and sub grade thickness for compacted soil under given traffic load. APPARTAUS:CBR apparatus consisting of mould of 150mm dia with a base plate and a collar, a 50mm dia, gauge for measuring expansion soaking and penetration FIGURE :- THEORY :- Hence This method was originally devised by O. J. Parter, then the California State Highway, by other authority in USA, notably the US Corporation Of Engineering. The method combines a load penetration test perform in a lab. This is probably the most widely used method for the design of flexible pavement. The thickness of various elements comprising a p avement is determine by CBR values. It is a small scale p enetration test in which a cylindrical plunger 5 mm dia. is pen etrated into a soil mass. The observation are taken between the penetr ation resistance into a soil mass at the ratio of 0.05 inch / min [1.25 mm / min ]. The observations are tak en between the penetration resistance verses the penetration of plunger. The California Bearin g Ratio is defined as the ratio of test load to the standard load expressed in percentage CBR = [Test Load / Standard load ] x 100 WORKING :The CBR test is carried on a compacted soil in a CBR 150 mm dia. and 175 mm height provided with a detachable collar of 50 mm deep to be kept in the mould during the sp ecimen penetration which enables a specimen of 1 25 mm deep to be obtained . The moulding dry density and water content should be same as it should be maintained during field compaction. To estimate th e worst moisture condition of the field, the specimen is submerged in water for about 4 days before testing. Generally CBR value for both soaked and unsoaked sample and determined both during soaking and penetration the specimen is carried with equal surcharge weights to estimate the effect of overlying parameters or particular layer under construction . Each surcharge weight 147 mm dia with a general hoe of 153 mm in did and weighing 2.5 kg is considered approximately equivalent to 6.5 cm of construction . A minimum of two weights are placed as sp ecimen load is applied on the penetration piston to obtained the penetration of 1.25 mm / min . The max imum load and penetration is recorded if it occurs for penetration less than 7 mm. PROCEDURE :The soil sample approximately 2000 gm is weighted and transformed in a tray . About 7 % of water of total weight of soil sample is added in the soil and mix it properly This moisturized sample is compacted in the CBR in different layers . Each layer is compacted by giving 56 no of blows by tamp ering rod . After compaction the mould is placed under CBR testing machine and adjusted properly . The load is applied gradually by this pressure testing machine and various sets of r eadin g are taken until soil specimen fails. OBSERVATIONS:(i) Weight of rammer = (ii) Drop of rammer = (iii) No. Of layers computed = (iv) Blows per layers = (v) Wt. of empty mould = (vi)Wt. of mould + compacted soil = (vii) Volume of mould = (viii)Water content of soil = (by oven dried method) (ix) Wt. of empty tray = Plunger Dia = Surcharge Wt. = Test end of specimen = 1 div Proving ring constant = 1 div = = PENETRTIO PROVING PROVINGLOAD CBR = PLU NGON ESTANDARD R LOAD N RING RING TEST LOAD (KG) (KG ) CONSTANT READING X 100 STD. LOAD CALCULATION:(1) For penetration 2.5 mm (corrected) CBR = X 100 = 1376 (2) For penetration 5mm (corrected) % CBR = X 100 = 2055 CORRECCORREC TEST TED CBR TED LOAD VALUR The sub grade thickness is given by 1.75P t = CBR Where t = A 9 Sub grade thickness CBR = CBR Value P = Wheel Load = 4500 kn A = Area of sub grade contact P A = p = 6.5kg/cm2 p RESULT:(1) The CBR value for 2. 5mm penetration is found to be = _______ (2) The CBR value for 5 mm penetration is found to be = ________ APPLICATION :This test is meant for soils and also carried out on the sub base and granular base coarse material . The CBR Test values are made use if an imperial method of flexible pavement design Grade of load Depth of construction on in cm A B C D E F G 31 38 44 50 56 64 70 Traffic density No. of commercial vehicle per day exceeding 3 + loaded wt. 0 - 15 15 - 45 45 - 150 150 - 450 450 - 1500 1500 - 4500 Above 4500 EXPERIMENT NO AIM: - To perform penetration test on the given sample of bitumen APPARATUS :- Penetrometer is penetration test apparatus FIGURE :THEORY :The penetration test determines the hardness and so ftness of bitumen by measuring the depth of needle in mm to which a standard loaded needle penetrates vertically 5 sec . The sample is maintained at 250 C. PROCEDURE :A bitumen sample of depth about 15mm. is taken into a container . The sample is arranged on the instrument that the standard needle just touches the surface of the bitumen sample . The dial is set to zero . Now initial reading is taken and the needle is released for 5 sec. and the final reading is taken on the dial gauge . Three reading should be tak en. Each test should be performed for at least 10 min apart from each other and the mean value is taken . OBSERVATION TABLE :Sr No. 1 2 3 4 5 Initial Reading 1/10 mm Final Reading 1/10 mm Differ ence 1/10 mm Penetration Value Average Penetration Value RESULT :The average penetration of the given sample (bitumen ) is found to be _____________ mm. PRECAUTION :1)The needle should be cleared properly before taking nex t reading . 2)The needle should just touch the bitumen. 3)Minimum 10 min should be maintained between the reading . APPLICATION :It is the most adopted test for bitumen depending on climate condition , type of construction Various bitumen used in permanent constant range between 20 to 25 . EXPERIMENT NO AIM :- To determine the crushing value of aggregate by aggregate crushed test APPARATUS :Steel cylinder of 152 cm diameter with a base plate and and plunger compression testing machine , sieves , aggregate etc. FORMULA :- % Crushing Value = [W3 / (W2 – W1 )] x 100 Where W1 = Weight of empty mould = __________ Kg W2 = Weight of mould + Aggregate = __________ Kg W3 = Weight of pan + crushed aggregate = ___________ Kg FIGURE :- THEORY :The strength of coarse aggregate may be determine by aggregate crushing strength test . The aggregate crushing value provides a relative measure resistance to the crushing order .Gradually applied compression load , to achieve a high resistance to crushing or low aggregate crushing value are performed . PROCEDURE :Dry aggregate passin g through 12.5 mm sieve and retained on 10 mm sieve is filled in the cylinder in three layers . Each layer being compacted b y 25 blows of tamping rod of diameter 16 mm.Then the plunger is placed on the top of the specimen and a load of 40 ton es/ min is applied b y the compression machine .The crushed aggregate are removed and sieved in 2.35 mm sieve . The material which passes through this sieve is weighed (Ws ). The value of aggregate is in percentage o f crushing material passing through 2.35 mm sieve in term of original weight of specimen . OBSERVATION :W1 = Weight of empty mould = ___________Kg W2 = Weight of mould + Aggregate = __________ Kg W3 = Weight of pan + crushed aggregate = ___________Kg CALCULATION :- % Crushing Value = [W3 / (W2 – W1 )] x 100 RESULT :The crushing value of the given aggregate is found to be ___________ % PRECAUTION :1)Length of the three layers should be approximately equal . 2)Aggregate should be perfectly dry . 3)Mould should be perfectly dry and clean . 4)Sieving should be done carefully. APPLICATION :Stone aggregate gives low crushing value . The crushing value of good quality aggregate to be used in base coarse should not ex ceed 45 % and the value for the surface co arse should not be less than 30 %. EXPERIMENT NO AIM :- To determine ab rasion value of coarse aggregate by Los Angelis Abrasion Testing Machine. APPARATUS :Los Angelis Abrasion Testing Machine , aggregate , cast iron , spear , 17 mm sieve FIGURE :- THEORY :The principle of Los Angelis Abrasion Test is to find out percentage valu e due to the relative rubbing action between the aggregate and the steel ball which are used as an ab rasion char ge . PROCEDURE :The test procedure co nsists of a rotating drum . It is rotated at a speed of 20 – 30 rpm . In this cylinder the sample along with the balls is added . The total weight of sample depends upon the size of aggregate and number of steel balls and weight of each steel balls . Maximum weight of steel ball is limited to 5 Kg . The sample and the steel ball are rotated upto 500 revolution . After completion of revolution , the sample is taken out . It is allowed to pass through 1.7 mm sieve size . The percentage weight passing is called abrasion value of aggregate. OBSERVATION TABLE :Weight of aggregate = _________ gm (W1 ) Sr No Sieve Size (mm) Weight Retained W(gm) Cumulative Weight retained (gm) %Cumulative Weight % Finess 1 2 3 4 5 6 7 Weight of sample passing through 1.7 mm Sieve (W2 ) = _________ gm CALCULATION :Abrasion value of a given aggregate sample = RESULT :Abrasion value is found to be _________ % of given aggregate sample by Los Angelis Abrasion Testing Machine. PRECAUTION :1) Aggregate should be taken by specific size because number and weight of steel balls depends upon size of aggregate . 2) Revolution of rotating drum should be rotated and noted perfectly. APPLICATION :Abrasion are carried out to test the hardness properly of coarse aggregate and d ecide wheth er they are suitable for different road construction work. The Los Angelis Abrasion value of good quality accepted for cemen t concrete , bituminous concrete or other high quality bituminous material should be less than 30% . Here percentage of fines or abrasion value is 10 % , which is less than 30 % and hence given specimen is accepted . This test is carried out to test the hardness properly of coarse aggregate and to decide whether they are suitable for road construction work The test is the best to found out the hardness of aggregate EXPERIMENT NO AIM :- To determine the softening point for the given sample of bitumen APPARATUS :Softening point test set up . FIGURE :- THEORY :The softening point of any substance is the temperature at which the substance attain a particular degree of softening under specified condition of test . The softening point of bitumen is generally found o ut by using ring and ball apparatus. PROCEDURE :A brass ring containing test sample of bitumen is suspended in liquid like water . Some times glycerin can be taken at a given bitumen sample and set up is placed in liquid . The liquid is heated after due coarse of time the steel ball fall down because the bitumen is very soft . Th e temperature at which the ball falls is called as softenin g point . Hard bitumen softens at high temperature. OBSERVATION TABLE :Ball No. Temperature at which b all falls CALCULATION :Softening Point = RESULT :The softening point of given of bitumen sample is found to be ______ 0C . PRECAUTION :1)The rate of increase of temperature should be uniform . 2)The stirrer should be used. DISCUSSION :Temperature at which the substance attends a particular degree of softening , This temperature must be kept in mind by the engineer while construction works. Hard grade bitumen posses higher softening than soft grade bitumen . Therefore the grade of bitumen can be determine by the test . APPLICATION :The softening point of bitumen is found to check whether is above the highest surface temperature ,else the bitumen may get slippery . In slippery the bitumen may even slide down if the softening point is less .
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