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Questions and Answers
What is the lead time to consider for a quality test of a cement sample?
What is the lead time to consider for a quality test of a cement sample?
Which property of concrete is not included in the list provided?
Which property of concrete is not included in the list provided?
What is the minimum time to remove forms and false works for columns?
What is the minimum time to remove forms and false works for columns?
Which class of concrete is used in heavily reinforced substructures?
Which class of concrete is used in heavily reinforced substructures?
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What is the purpose of a pile cap in construction?
What is the purpose of a pile cap in construction?
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What is the minimum time required for the removal of forms for floor slabs?
What is the minimum time required for the removal of forms for floor slabs?
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What is the flexural strength required for a concrete beam tested by the Third-Point Method after 14 days?
What is the flexural strength required for a concrete beam tested by the Third-Point Method after 14 days?
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What class of concrete is used for thin reinforced sections such as railings?
What class of concrete is used for thin reinforced sections such as railings?
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What is the required weight of a sample for testing coarse aggregates used for concreting?
What is the required weight of a sample for testing coarse aggregates used for concreting?
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Most specifications for concrete exposed to weathering require a water-cement ratio of what value?
Most specifications for concrete exposed to weathering require a water-cement ratio of what value?
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Which test of cement determines the amount of water required to prepare hydraulic cement?
Which test of cement determines the amount of water required to prepare hydraulic cement?
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If a concrete road section fails to meet specified strength requirements, what should be recommended?
If a concrete road section fails to meet specified strength requirements, what should be recommended?
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What are materials added to the concrete mix to modify its properties called?
What are materials added to the concrete mix to modify its properties called?
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What is the heat produced by the chemical reaction of cement and water known as?
What is the heat produced by the chemical reaction of cement and water known as?
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Cylinder samples should have their ends capped if they are not plane within what measurement?
Cylinder samples should have their ends capped if they are not plane within what measurement?
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What type of cement should be stored in elevated, air tight, and weatherproof bins?
What type of cement should be stored in elevated, air tight, and weatherproof bins?
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What is the minimum thickness of conventional concrete for the surface course in monolithic pavement?
What is the minimum thickness of conventional concrete for the surface course in monolithic pavement?
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How many specimen samples are needed to test concrete hollow blocks per 10,000 units?
How many specimen samples are needed to test concrete hollow blocks per 10,000 units?
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Which test determines the consistency of concrete?
Which test determines the consistency of concrete?
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What are the dimensions of a standard concrete cylindrical sample?
What are the dimensions of a standard concrete cylindrical sample?
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What is the minimum compressive strength required for class A concrete?
What is the minimum compressive strength required for class A concrete?
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A tie bar should be made of which type of bar?
A tie bar should be made of which type of bar?
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What constitutes the mortar for masonry units?
What constitutes the mortar for masonry units?
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What is the positional tolerance of duct tubes during casting operations?
What is the positional tolerance of duct tubes during casting operations?
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What is the maximum jacking force for the specified minimum ultimate strength of the steel tendon?
What is the maximum jacking force for the specified minimum ultimate strength of the steel tendon?
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Where and when was the first use of Portland cement?
Where and when was the first use of Portland cement?
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After completing the stressing operation, steel tendons should be grouted within how many hours?
After completing the stressing operation, steel tendons should be grouted within how many hours?
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What is the sample type used for compressive strength determination of structural concrete?
What is the sample type used for compressive strength determination of structural concrete?
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What is the minimum grouting pressure needed?
What is the minimum grouting pressure needed?
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What is the required maximum clear opening for grout screens?
What is the required maximum clear opening for grout screens?
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What is the test used to determine the consistency of concrete?
What is the test used to determine the consistency of concrete?
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What is the minimum thickness and covering for rubble concrete?
What is the minimum thickness and covering for rubble concrete?
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How many samples should be taken for every 75 cu.m of fresh concrete?
How many samples should be taken for every 75 cu.m of fresh concrete?
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How long must concrete be cured by the ponding method at a minimum?
How long must concrete be cured by the ponding method at a minimum?
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What is the temperature that should be maintained when curing a sample after its initial curing?
What is the temperature that should be maintained when curing a sample after its initial curing?
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What percentage can super plasticizers reduce the water content of concrete?
What percentage can super plasticizers reduce the water content of concrete?
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What is the size of the tamping rod used in tampering concrete samples?
What is the size of the tamping rod used in tampering concrete samples?
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What is the maximum insertion time for a vibrator in a concrete mix?
What is the maximum insertion time for a vibrator in a concrete mix?
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What percentage above the mixer’s nominal capacity may be permitted for concrete mixing?
What percentage above the mixer’s nominal capacity may be permitted for concrete mixing?
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Which class of riprap may consist of round natural stones?
Which class of riprap may consist of round natural stones?
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What is the maximum projection of rock faces beyond the pitch lines?
What is the maximum projection of rock faces beyond the pitch lines?
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Which option correctly states the reason for not using sea water in reinforced concrete?
Which option correctly states the reason for not using sea water in reinforced concrete?
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What is the boundary sieve designation between coarse and fine aggregates?
What is the boundary sieve designation between coarse and fine aggregates?
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How many weeks after the coring test result can the contractor request for re-coring?
How many weeks after the coring test result can the contractor request for re-coring?
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What is the PH value range of water used in concrete?
What is the PH value range of water used in concrete?
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The revised design strength for concrete pavement was changed to 7 days for national roads and how many days for major interchanges?
The revised design strength for concrete pavement was changed to 7 days for national roads and how many days for major interchanges?
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What compressive strength should mortar samples reach at 7 days for acceptance?
What compressive strength should mortar samples reach at 7 days for acceptance?
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Study Notes
Materials Engineers (DPWH) Accreditation Exam Review II
- Portland Cement First Use: Bellafonaine, Ohio (1893)
- Portland Cement Inventor: Joseph Aspdin
- Structural Concrete Sample: Concrete Cylinder Sample
- Concrete Consistency Test: Slump Test
- RSB Sample Length: 1.0m / 10,000 kg/size/shipment
- Samples per 75 cu.m Fresh Concrete: 1 set of 3 pcs.
- Cement Bags per 10 kg Sample: 2000 bags
- Magnesium Oxide Test: Used for cement
- Curing Temperature: 23°C ± 1.7°C (63°F to 85°F)
- Curing Time After Initial Curing: 3 hours
- Concrete Mixer Overload: 10% above nominal capacity
- Vibrator Insertion Time: Not to exceed 15 seconds at 50-60 cm intervals
- Core Deficiency Measurement: At least 5 meters parallel to the centerline in each direction
Slump Test and Concrete Properties
- Slump Test Purpose: Defines concrete consistency (workability, fluidity, and density).
- Slump Test Exclusions: Job density
- Concrete Core Measurement Thickness: Using calliper, measured at 9 locations
- Failed Sample Explanation: Sampling issues, not necessarily structural defects
- Concrete Water Amount (1:2:4 mix): Approximately 20 liters
Concrete Mixing Requirements
- Mortar Mix for Item 505 (Stone Masonry): 1:2 (1 part cement, 2 parts sand)
- Mortar Mix for Item 500 (Pipe Culverts and Storm Drains): 1:2 (1 part cement, 2 parts sand)
- Concrete Pavement Opening Delay: 14 days
- Concrete for Road Opening Delay: 14 days after placement
- Concrete Slump (for slip-form paving): 11½ inches (40mm)
Other Concrete Considerations
- Concrete Deficiency Payment: 25% or greater
- Pavement Lot Length (Single Lane): 1,000 linear meters
- Pavement Lot Length (Double Lane): 500 linear meters
- Concrete Beam Sample Size: 150mm x 150mm x 525mm (6" x 6" x 21")
- Concrete Beam Sample Sets: 1 set per 330 sq.m.
- Compressive Strength Testing Minimum Age: 14 days
Concrete Construction
- Transverse Construction Joints: Cold joints (Concrete operation interruptions > 30 minutes)
- Dynamic Cone Penetrometer: Instrument to measure pavement structural properties
- Rebar Locator: Pinpointing rebar, conduit, metals in concrete
- Benkelman Beam and Deflection Logger: Measures pavement deflection under traffic load
Concrete Materials and Testing
- Type 1 Portland Cement: General Use
- Type III Portland Cement: High Early Strength
- Type IV Portland Cement: Low Heat of Hydration
- Type V Portland Cement: Sulfate Resistance
- Cement Compositions: Primarily calcium, alumina, iron, silica
- Concrete Aggregate Types: Crushed rock, slags, river gravel
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Description
Prepare for the Materials Engineers Accreditation Exam with this comprehensive review focused on Portland Cement, concrete testing methods, and properties. This quiz covers key information such as the slump test, curing practices, and sample requirements essential for a successful accreditation. Test your knowledge on important concepts and enhance your readiness for the exam.
