DPWH Materials Engineer Exam March 2017
What is the phosphorus content requirement for rebars? A. 0.06 min. B. 0.06 max. C. 0.60 max. D. None of the above
0.06 max.
The mortar proportion of stone masonry shall be: A. One-part cement 2-parts sand B. One-part cement 3-parts sand C. One-part cement 4-parts sand D. One-part cement 1-part sand
1. One-part cement, 2-parts sand
When the top surface of a concrete specimen is rough and not truly plane stress concentrations are introduced and the strength of the concrete is reduced by about: A. 1/2 B. 1/3 C. 1/4 D. 1/5
1/3
A concrete core specimen for thickness determination shall have a diameter of at least: A. 75 mm B. 100 mm C. 125 mm D. 150 mm
100 mm
In how many equal layers should a concrete cylinder beam sample be molded? A. 2 B. 3 C. 4 D. 5
2
In the construction of a 2-storey G-classroom school building, an estimated 18800 units of 4" CHB will be used. How many quality tests are you going to perform? A. 4 QT B. 3 QT C. 2 QT D. None of the above
2 QT
If 330 gallons of paint for use in painting a 2-storey school building are delivered to the project, 160 gallons are Latex Paint and 140 gallons are flat wall enamel paint. How many gallons will you submit for quality test for each type of paint? A. 1 gallon each B. 2 gallons each C. 4 gallons each D. None of the above
2 gallons each
A one-lane pavement width of 3.5 meters and shoulder width of 9.5 meters on each side of the pavement was designed to have subbase and base courses with a combined thickness of 300 mm. If the thickness of the subbase is 125 mm, the spreading and compaction of the subbase and base courses shall be carried out in: A. 3 layers over the full width of 4.5 m B. 2 layers over the full width of 4.5 m C. 3 layers over the full width of 3.5 m D. 2 layers over the full width of 3.5 m
2 layers over the full width of 4.5 m
If the bulk specific gravity of a bituminous mix is 2.243 and the dry stability is 3100 lbs, what will be the approximate wet stability if its Index of Retained Strength (IRS) is 82%? A. 2542 lbs B. 3780 lbs C. 5702 lbs D. 6953 lbs
2,542 lbs
Given: Asphalt content of bituminous mix = 5.5% Weight of specimen in air = 1200g Weight of specimen in water = 700g Weight of specimen in SSD = 1205g Calculate the bulk gravity of the asphalt specimen. A. 1.174 B. 1.721 C. 1.576 D. 2.376
2.376
The specification calls for a 12:4 concrete mix. In a one-bagger mixer, which of the following amounts of water is most likely required for the mix? A. 20 liters B. 5 liters C. 10 liters D. 35 liters
20 Liters
Specimens for compressive or flexural strength tests shall be removed from the molds at the end of 24 hours and stored in a moist condition at a temperature range of ___ until the time of test. A. 24 to 28 degrees Celsius B. 22 to 26 degrees Celsius C. 20 to 24 degrees Celsius D. 18 to 22 degrees Celsius
20 to 24 degrees celsius
The maximum compacted thickness per layer for both aggregate subbase and base courses (Items 200 and 201) is ___. A. 125 mm B. 150 mm C. 175 mm D. 200 mm
200 mm
Bituminous mixture shall have a minimum dry compressive strength of: A. 100 psi B. 200 psi C. 300 psi D. 400 psi
200 psi
Concrete samples must be shipped to the laboratory at least ___ hours prior to testing. A. 12 B. 24 C. 36 D. 48
24
Specimens for compressive or flexural strength tests shall be removed from the molds at the end of ___ hours and stored in a moist condition until the time of test. A. 12 B. 24 C. 36 D. 48
24
Blended hydraulic cement type IP requires a compressive strength requirement of ___. A. 25 MPa min. B. 25 MPa max. C. 28 MPa min. D. None of the above
25 MPa min.
If one of the measurements of a core specimen taken from the concrete pavement is 28.7 cm, what is the corrected measurement to be used in calculating the average thickness of the pavement if the design thickness is 28.0 cm? A. 28.7 cm B. 28.0 cm C. 28.5 cm D. 29.0 cm
28.5 cm
DPWH Department Order No. 47 Series of 2015 requires an International Roughness Index (IRI) values of not more than ___ for both asphalt and pavement for National Primary Roads. A. 2.00 m/Km B. 2.50 m/Km C. 3.00 m/Km D. 3.5 m/Km
3.00 m/km
A load-bearing concrete hollow block (CHB) sample was tested to compression with the following test data: Width = 150 mm Length = 394 mm Height = 194 Ultimate load = 52300 lbs What is the compressive strength of the sample? A. 2.8 MPa B. 3.9 MPa C. 4.2 MPa D. None of the above
3.9 MPa
What is the yield point and tensile strength in MPa of a 16 mm diameter deformed steel bar with the following data? Nominal mass = 1.552 kg/m3 Nominal area = 199 sq. m Yield point load = 15900 lbs Tensile load = 20800 lbs A. 250 MPa and 490 MPa B. 355 MPa and 465 MPa C. 380 MPa and 510 MPa D. None of the above
380 MPa and 510 MPa
What is the required length of pipe specimen in the determination of zinc coating of galvanized pipe? A. 6 in. B. 4 in. C. 2 in. D. None of the above
4 in
Compute the percent variation in a mass of a 19mm diameter deformed steel bar with the following laboratory test data: Length of specimen = 1000 mm Mass of specimen = 2.322 Kg Nominal mass = 2.235 Kg/m Nominal Area = 284 sq. m A. 6% B. 4% C. 3% D. None of the above
4%
During asphalt compaction the rolling speed whether being used in the vibratory or static mode should not exceed ___ km/hr. A. 4-7 B. 5-8 C. 6-9 D. 7-10
4-7
In Portland cement, the amount of water in the preparation of mortar cubes can be determined using what water/cement ratio? A. 0.485 B. 0.458 C. 0.585 D. None of the above
485
Given Weight of Dry Aggregates = 950 grams, Weight of Asphalt = 50 grams, what is the percent of asphalt by weight of total mix? A. 5% B. 5.26% C. 5.55% D. 6%
5%
The best way to determine the temperature of the delivered asphalt mix is with a dial and armored stem thermometer. The stem should be inserted sufficiently into the mixture to a depth of at least: A. 2 inches B. 4 inches C. 6 inches D. 8 inches
6 inches
Undersized reinforcing steel bars that satisfy the tensile and elongation requirements may be accepted provided that its underweight does not exceed: A. 3% B. 5% C. 6% D. 10%
6%
The required strength of a concrete beam sample is at least ___ when tested by mid-point method. A. 550 psi B. 650 psi C. 3000 psi D. 3500 psi
650 psi
The index of retained strength of the compacted bituminous mixtures is the ratio of the compressive strength of immersed and dry bituminous mixture. What is the minimum index of retained strength required for bituminous mixtures? A. 40% B. 50% C. 60% D. 70%
70%
From the following data, determine the degree of compaction. Field density test data: Weight of material taken from hole kg = 4.885 Weight of sand to fill hole kg = 3.885 Volume of hole cu.m = 0.0028 Wet unit weight kg/cu.m = 1745 Dry unit weight kg/cu.m = 1663 Laboratory Data: Maximum dry density kg/cu.m = 2250 Optimum Moisture Content % = 8.10 A. 74% B. 78% C. 95% D. 105%
74%
What is the minimum soaked CBR value required for base materials obtained at the maximum dry density determined by AASHTO T 180 Method D? A. 25 B. 50 C. 75 D. 80
80
A sample of a Reinforced Concrete Pipe has the following test data: Dimensions:Actual Internal Diameter = 915 mmThickness of Wall = 115 mmLaying length = 1000 mm (1m) Strength Tests:Load to produce 0.3mm crack = 7435 KgUltimate load = 8160 Kg What is the load to produce 0.3 mm crack and the ultimate load? A. 84 N/mm and 101 N/m/mm B. 80 N/mm and 87 N/m/mm C. 57 N/mm and 66 N/m/mm D. None of the above
80 N/mm and 87N/m/mm
What penetration grade of asphaltic material is appropriate for sealing of PCCP joints? A. 85-100 B. 120-150 C. 150-200 D. Not exceeding 90
85-100
Compaction trials on embankment and base/subbase courses are carried out to determine the: A. Suitable type of compaction equipment to be used B. Number of roller passes required C. Suitability of the materials D. All of the above
All of the above
From the materials point-of-view, subgrade construction consists mainly of: A. Compaction of the top layer in cuts B. Compaction of the whole depth of material in embankments C. Identification and treatment of unsuitable material D. All of the above
All of the above
The moisture-density curve is different for each soil. Which of the following statements is/are true? A. Granular well-graded soils generally have fairly high maximum densities at low optimum moisture content (OMC) B. Clay soils have lower densities at OMC than granular well-graded soils C. Granular well-graded soils have higher densities than uniform soils at OMC D. All of the above
All of the above
The purpose of conducting laboratory CBR test on the fill materials for embankment is to check: A. Permeability of the compacted subgrade material B. Swelling characteristics of the subgrade material C. Bearing capacity of subgrade material D. All of the above
All of the above
In slip-form construction, what is the slump of concrete used? A. Not more than 3 inches B. 3 to 4 inches C. Almost zero D. Any of the above
Almost zero
As a materials engineer, when is the right time to start the sampling and testing of aggregate base course material? A. Once the material is delivered and stockpiled B. As construction work progresses C. Once the source is identified D. After the material was incorporated into the work
As construction work progresses
The asphalt material that is usually classified by its penetration grade is: A. Joint filler B. Emulsified asphalt C. Cutback asphalt D. Asphalt cement
Asphalt cement
When the strength test results of concrete beam samples are not acceptable, how many representative core(s) shall be taken from each member or area of concrete in-place considered deficient in the newly completed concrete pavement? A. At least 4 cores B. At least 3 cores C. At least 2 cores D. Only 1 core
At least 3 cores
Which of the following is the frequency of sampling of concrete beams required by DPWH specification? A. At least one set of 3 concrete beams every 50-cu.m or fraction thereof B. At least one set of 3 concrete beams every 500-cu.m or fraction thereof C. At least one set of 3 concrete beams every 75-cu.m or fraction thereof D. At least one set of 3 concrete beams every 750-cu.m or fraction thereof
At least one set of 3 concrete beams every75-cu.m. or fraction thereof
Where do we take additional cores when the measurement of any core taken from the pavement is deficient in thickness by more than 25 mm? A. At no less than 20-meter intervals parallel to the centerline in each direction from the affected location B. At no less than 15-meter intervals parallel to the centerline in each direction from the affected location C. At no less than 10-meter intervals parallel to the centerline in each direction from the affected location D. At no less than 5-meter intervals parallel to the centerline in each direction from the affected location
At no less than 5-meter intervals parallel to the centerline in each direction from the affected location.
For efficient compaction, the embankment materials should at the time of rolling be: A. Dry B. Wet C. At optimum moisture content D. At maximum moisture content
At optimum moisture content
Generally, acceptance of concrete pavement is based upon: A. Cores B. Beam samples C. Both A and B D. Either A or B
Both A) and B)
The test which combines a load-deformation test performed in the laboratory with an empirical design chart to determine the thickness of pavement base and other layers is known as: A. Plate bearing test B. Moisture-Density Determination C. California Bearing ratio D. Standard Penetration Test
California bearing ratio
ASTM C150 requires that the 28-day strength of mortar made from Type I Portland cement be at least 27.6 MPa. Three specimens were tested: two passed but one failed by more than 20%. What will be the conclusion? A. Discard the failed result and conclude that the particular cement passed the specification B. Perform a re-test since the data is inconclusive C. Get the average of the three and if the average is more than 27.6 MPa conclude that the particular cement passed the specification D. Conclude that the cement does not pass the specifications since it failed to give the consistent results
Conclude that the cement does not pass the specifications since it failed to give the consistent result.
A set of three (3) beam samples representing a particular section of a concrete pavement failed to meet the flexural strength requirement. As a materials engineer, what would you recommend? A. Monitor the pavement section with strength deficiency B. Adjust payment corresponding to the strength deficiency of the beam samples C. Conduct core test for strength determination on section represented by the failed samples to determine the actual strength of the in-placed concrete D. Submit new beam samples for testing
Conduct core test for strength determination on section represented by the failed sample to determine the actual strength of the in-placed concrete.
Three cores taken from a pavement section poured on a single day were tested to have strengths as follows: +-------+----------------------+ | Core | Strength (psi) | +-------+----------------------+ | 1 | 3650 | | 2 | 3000 (86% of 3500 psi)| | 3 | 2450 (70% of 3500 psi)| +-------+----------------------+ | Average | 3033 (87% of 3500 psi) | +-------+----------------------+ If the required strength is 3500 psi, concrete in the area represented by these cores: A. May be accepted subject to price adjustment B. Considered adequate C. Considered inadequate D. May be recorded at the initiative of the DPWH
Considered inadequate
Penetration test for asphalt cement is a measure of: A. Consistency B. Solubility C. Ductility D. Fluidity
Consistency
Quality Control testing in a DPWH project is the responsibility of the: A. DPWH B. Contractor C. DPWH and Contractor D. Construction Supervision consultant
Contractor
The actual strength of concrete in-place in an area represented by failed beam samples can be determined by means of: A. Slump test B. Core test C. Stability test D. Extraction test
Core test
Two concrete cylinders, A and B, are tested in uniaxial compression. If cylinder A is completely saturated while B is dry, which of the following is true? A. Both cylinders will yield the same compressive strength provided that all of the factors are the same B. Whether cylinder A will yield a higher compressive strength over cylinder B (or otherwise) is unpredictable C. Cylinder A will yield a higher compressive strength D. Cylinder B will yield higher compressive strength
Cylinder A will yield a higher compressive strength
Asphalt increases in Marshall Stability Test the air voids: A. Increases B. Decreases C. Remains Constant D. Either A or B
Decreases
Cutback asphalt or emulsified asphalt is usually used for: A. Prime coating B. Tack coating C. Seal coating D. Either A or B
Either A and B
What is the frequency of core sampling required on a completed bituminous pavement? A. Every 100 linear meters per lane B. Every 200 linear meters per lane C. Every 300 linear meters per lane D. Every 400 linear meters per lane
Every 100 linear meters per lane
Slump test is the measure of workability of concrete mixture. Which is NOT the type of concrete slump? A. Shear slump B. Collapse slump C. True slump D. False slump
False slump
The smaller the value of the fineness modulus the: A. Coarser the material B. Finer the material C. The lighter the material D. The drier the material
Finer the material
The test to indicate the temperature wherein asphalt can be heated without catching fire is called: A. Loss on heating B. Spot test C. Flash point D. Penetration test
Flash point
Cement stiffening without strength development is called ___. A. False set B. Flash set C. Premature set D. None of the above
Flash set
Which of the following gauge numbers of G.I sheets will give the lower thickness? A. Gauge # 32 B. Gauge # 31 C. Gauge # 26 D. Gauge # 18
Gauge # 32
Under what climatic condition(s) do we use the lower penetration grade or hard asphalts? A. Cold climate B. Hot climate C. Both cold and hot climate D. Rainy weather
Hot climate
Retarders are more useful during: A. Cold weather B. Hot weather C. Freezing weather D. Warm weather
Hot weather
What is the significance of the loss on ignition test of cement? A. It is a measure of the heat generated when cement is mixed with water. B. It signifies pre-hydration or moisture uptake of cement while it is shelved. C. It is a measure of the resistance of cement when exposed to fire. D. None of the above.
It signifies pre-hydration or moisture uptake of cement while it is shelved
What differentiates the composition of Item 201 — Aggregate base course and Item 200 — Aggregate Subbase Course? A. Item 201 contains less binder and smaller size of gravel than Item 200 B. Item 201 contains more binder and bigger size of gravel than Item 200 C. Item 201 contains sand and gravel only D. Item 201 contains sand and fine-grained soils only
Item 201 contains less binder and smaller size of gravel than item 200
A mixture of asphalt cement and water with catalytic agent is called: A. Joint filler B. Temperature asphalt C. Cutback asphalt D. Asphalt cement
Joint filler
Which of the following bituminous materials is best recommended for sealing weakened plane joints? A. Asphalt cement B. Emulsified Asphalt C. Cutback Asphalt D. Joint filler asphalt
Joint filler asphalt
The optimum moisture content of soil is determined during: A. Laboratory compaction B. Compaction of a trial section C. Field compaction test D. Any of the above
Laboratory compaction
This is the type of paint intended for concrete and other masonry surfaces. A. Enamel paint B. Latex Paint C. Polyurethane Paint D. None of the above
Latex Paint
Which of the following is the thinnest and most fluid of medium curing cutback asphalt? A. MC-30 B. MC-70 C. MC-250 D. MC-800
MC-800
It is a single test procedure to determine the suitability of an asphaltic concrete mix. A. Penetration B. Extraction C. Marshall Stability D. Immersion-Compression
Marshall stability
Under D.O 98 series of 2016 Revised Guidelines on the Accreditation of Contractors' and Consultants' Materials Engineers which is NOT true in the Limits of Assignment of accredited Materials Engineers. A. Non-accredited Materials Engineer — Three (3) projects with an aggregate cost of not more than P 15M B. Materials Engineer I — Two (2) projects with an aggregate cost of not more than P 200M C. Materials Engineer Il — Two (2) projects with an aggregate cost of not more than P300M D. Materials Engineer Il — Three (3) projects with an aggregate cost of not more than P 250M
Materials Engineer 1-two (2) projects with an aggregate cost of not more than P200M
What documentation should be maintained and kept updated by the materials engineer during project implementation? A. Minimum testing requirements B. Materials logbook C. Quality control handbook D. Materials test result
Materials logbook
An estimated 15200 units of corrugated G.I. sheets will be used in the construction of a resettlement housing project. How many quality tests are you going to prepare? A. 13 QT B. 10 QT C. 9 QT D. None of the above
None of the above
When taking three or more samples of aggregates to be combined for one materials sample: A. The small samples must be packed in separate sample bags B. The small samples must be obtained from different lots C. The small samples should be of approximately equal size D. None of the above
None of the above
Suppose you have a sack of aggregate sample weighing 20 Kg. But you only need 5 Kg for a certain test. In the absence of sample splitter, what will be the best way to get a 5 Kg sample? A. Get a 5 Kg sample from the middle of the sack B. Remove the aggregate from the sack and lay it a pile on a clean floor then get the 5 Kg sample from the middle of the pile C. Perform the quartering procedure D. Get a 5 Kg sample direct from the sack
Perform the quartering procedure
Which is not included in the three phases of rolling operations in asphalt pavement? A. Breakdown rolling B. Primary rolling C. Intermediate rolling D. Final rolling
Primary rolling
Samples of aggregate base course material when tested for quality passed the requirements except grading. What will you recommend as a materials engineer? A. Reject the material B. Replace the material C. Accept the material at an adjusted price D. Reprocess the material by blending
Reprocess the material by blending
An admixture that tends to reduce the incidence of thermal cracking and maintain concrete workability during large pours or long ready-mix hauls is a/an: A. Water-reducing admixture B. Retarding water-reducing admixture C. Air-entraining admixture D. Accelerating admixture
Retarding water-reducing admixture
Test pitting conducted on a prepared base showed that the thickness of Item 201 — Aggregate base course was deficient by 5 cm. As a materials engineer, what will you recommend? A. Reject the prepared section B. Rework the section C. Accept the section at an adjusted price due to thickness deficiency D. Provide sand cushion to attain the thickness requirement
Rework the section
The selection by standard method of a representative portion of a material for the purpose of ascertaining its characteristics is called: A. Batching B. Sampling C. Quarrying D. Quartering
Sampling
Too wet mix over-sanded mix and overworking of concrete during placing usually result in ___ of concrete pavement. A. Cracking B. Ravelling C. Settlement D. Scaling
Scaling
Which schedule number of G.I Pipe will give a high wall thickness? A. Schedule 80 B. Schedule 40 C. Schedule 20 D. None of the above
Schedule 80
The main problem associated with the wrong practice of conveying concrete is called: A. Honeycomb B. Laitance C. Segregation D. Cracking
Segregation
How many pipes should be tested for strength absorption and dimension in 300 pcs of reinforced culvert pipe? A. One B. Two C. Four D. Six
Six
The sieving process (grain size) does NOT provide information on: A. Shape of the soil grains B. Distribution of the grain sizes C. Soil classification D. Both B and C
Soil classification
Soil properties can be improved by: A. Adequate Compaction B. Addition of Binder C. Maximizing water content D. Stabilization
Stabilization
For RCPC, the laying length used in calculating the strength values of the barrel pipe is the: A. Outside length B. Inside length C. Standard length D. None of the above
Standard length
Which of the following provisions is not included in the job-mix formula? A. Mixing time B. Grading of Aggregates C. Asphalt cement D. Temperature at delivery
Temperature at delivery
The workability of a bituminous mix is dependent on the: A. Gradation of aggregates B. Temperature of mix C. Asphalt content D. Shape and texture of aggregates
Temperature of mix
Quality of factory-produced reinforced concrete pipes may be best established through: A. Engineer's Certification B. Inspection Report C. Test of concrete cylinder samples D. Test of concrete pipe samples
Test of concrete pipe samples
Embankment materials are classified as unsuitable materials if: A. The natural moisture content is 50% B. The liquid limit is 40% C. The plasticity index is 60 D. The natural density is 1200 Kg per cubic meter
The plasticity index is 60
What is the function of emulsifiers in liquid asphalt? A. To increase mixing ability with aggregates B. To retain water in asphalt for longer periods C. To prevent asphalt from hardening D. To enable asphalt and water to mix
To enable asphalt and water to mix
Why are undisturbed samples used primarily for determining the properties of foundation materials? A. To retain the structure of material B. Because it is easier to obtain undisturbed sample than disturbed samples C. Because it is easier to test undisturbed samples than disturbed samples D. Because it represents the relative strength of the soil strata when subjected to compression test
To retain the structure of material
What chemical admixture is needed to produce a concrete mix with improved slump without additional water? A. Set accelerating admixture B. Set retarding mixture C. Water reducing admixture D. Fly ash
Water reducing admixture
What test is conducted to clarify reinforcing steel bars into grade? A. Tensile Strength B. Yield Strength C. Elongation D. All of the above
Yield strength
What will possibly be the result of using different brands of cement in concrete paving? A. Different Strength B. Different Texture C. Different color after it has hardened D. No effect
different Strength
A transit mixer for road construction was found to have a 6" slump of fresh concrete instead of the required 3". What will you recommend if you are the assigned Materials Engineer? A. Add Portland cement to attain the required 3" slump B. Add Portland cement and fine aggregate to attain the required 3" slump C. Reject the concrete mixture D. Let the concrete mix be diverted for pouring on a prepared column for retaining wall of the same project
reject the concrete mixture
