Forensic Chemistry: Cement, Mortar and Concrete XRD Phase Analysis
Published:
Questions
31
Duration
30 min
Faculty-reviewed
0
Updated
25 May 2026
About this mock
UGC-NET Forensic Science Unit VII advanced drill covering the forensic characterisation of Portland cement systems by X-ray diffraction (XRD), SEM-EDX, FTIR, and oxide chemistry. Questions test IS 269, IS 1489, IS 12269, and IS 455 composition limits for OPC, PPC, and PSC; the four clinker phases alite (C3S, 50-70%%), belite (C2S, 15-30%%), aluminate (C3A, 5-10%%), and ferrite (C4AF, 5-15%%); hydration products CSH gel (Ca/Si approximately 1.7), portlandite (Ca(OH)2, XRD at 18.0 degrees 2-theta), and ettringite (AFt, XRD at 9.1 degrees 2-theta, FTIR at 1110 cm-1); fly-ash classification (Class C vs Class F per ASTM C618); silica fume specifications (ASTM C1240); GGBS hydraulic activity (IS 12089); and the Bogue calculation versus Rietveld XRD refinement for quantitative phase analysis.
Indian forensic science context runs through every sub-topic. CFSL Chandigarh's trace-evidence section uses the three-peak XRD fingerprint (ettringite 9.1 degrees, portlandite 18.0 degrees, alite 32.2 degrees) to confirm OPC-based mortar in IED pipe-bomb debris. SERC Chennai applies petrographic thin-section analysis and compressive-core testing under IS 456:2000 in structural-failure investigations. Construction fraud patterns -- substandard w/c ratio, cement-poor mixes, oversized aggregate, and adulteration with Class C fly-ash or off-spec GGBS -- are framed against IS 456:2000 Clauses 5.3 and 9, IS 12269:2013 chemical limits, and IS 455:2015 GGBS content limits. The 30-35 degrees 2-theta clinker XRD window (alite 32.2, belite 32.7, C3A 33.2, C4AF 33.8) and free-lime detection at 37.3 degrees 2-theta are tested as forensic evidence thresholds.
Topics covered:
- OPC, PPC, PSC composition limits under IS 269, IS 1489, IS 455, IS 12269
- Clinker phase ranges: C3S (50-70%%), C2S (15-30%%), C3A (5-10%%), C4AF (5-15%%)
- Hydration products: CSH gel (Ca/Si 1.7), portlandite (18.0 degrees 2-theta), ettringite (9.1 degrees 2-theta)
- Fly-ash Class C vs Class F (ASTM C618 SAF thresholds); silica fume (ASTM C1240)
- GGBS composition and IS 12089 hydraulic activity index (80%% at 28 days)
- XRD 2-theta peak map: ettringite 9.1, portlandite 18.0, alite 32.2, belite 32.7, C3A 33.2, C4AF 33.8
- SEM-EDX phase ID (Ca/Si for CSH; Ca+Al+S for ettringite); FTIR ettringite fingerprint (1110, 3300-3450, 870 cm-1)
- IED post-blast, building-collapse, and construction-fraud forensic interpretation
Calibrated for UGC-NET Paper II Unit VII top-decile candidates and NFSU MSc Forensic Chemistry entrance examinees. Allow 30 minutes.
Sources & references
Questions in this mock are written and verified against the following sources. Citations are recorded per question and shown in the explanation after submission.
- cited in 13 questions
Taylor, H.F.W. -- Cement Chemistry, 2nd Edition, Thomas Telford
Chapter 1: XRD Identification of OPC Clinker Phases -- Alite Peak Positions and Rietveld Application
- cited in 3 questions
Bureau of Indian Standards -- IS 456:2000 Plain and Reinforced Concrete Code of Practice (4th Revision)
Clause 9: Concrete Mix Proportioning, Minimum Cement Content and M20 Characteristic Strength
- cited in 2 questions
Saferstein, Richard -- Criminalistics: An Introduction to Forensic Science, 12th Edition, Pearson
Chapter 7: Inorganic Analysis and Trace Evidence -- XRD Identification of Cement in Post-Blast Debris
- cited in 2 questions
Bogue, R.H. -- Chemistry of Portland Cement, 2nd Edition, Reinhold Publishing
Chapter 3: Free Lime in OPC Clinker -- Formation, XRD Detection, and Soundness Implications
- cited in 1 question
Bureau of Indian Standards -- IS 12269:2013 Ordinary Portland Cement 53 Grade Specification
Clause 7: Physical Requirements, Table 1 Compressive Strength at 28 Days
- cited in 1 question
Mehta, P.K. and Monteiro, P.J.M. -- Concrete: Microstructure, Properties and Materials, 5th Edition, McGraw-Hill
Chapter 13: Supplementary Cementing Materials -- Fly Ash Particle Morphology and SEM Identification
- cited in 1 question
Bureau of Indian Standards -- IS 455:2015 Portland Slag Cement Specification
Clause 5: Composition, GGBS Content Limits
- cited in 1 question
ASTM C1240 -- Standard Specification for Silica Fume Used in Cementitious Mixtures
Section 6: Chemical and Physical Requirements, SiO2 Minimum and Fineness
- cited in 1 question
Richardson, I.G. -- The Nature of CSH in Hardened Cements, Advances in Cement Research
Section: SEM-EDX Characterisation of CSH -- Ca/Si Ratio Distribution in OPC Paste
- cited in 1 question
Bureau of Indian Standards -- IS 12089:1987 Specification for Granulated Slag for Manufacture of Portland Slag Cement
Clause 4: Chemical Composition Requirements for GGBS
- cited in 1 question
Bureau of Indian Standards -- IS 1489 (Part 1):2015 Portland Pozzolana Cement (Fly Ash Based)
Clause 5.1: Composition, Fly Ash Content Limits
- cited in 1 question
Bureau of Indian Standards -- IS 12089:1987 Granulated Slag for Manufacture of Portland Slag Cement
Clause 5.4: Hydraulic Activity Index at 28 Days -- Minimum 80%%
- cited in 1 question
Skoog, Holler, Crouch -- Principles of Instrumental Analysis, 7th Edition, Cengage
Chapter 17: Infrared Spectroscopy -- FTIR Identification of Inorganic Minerals including Ettringite
- cited in 1 question
Bureau of Indian Standards -- IS 269:2015 Ordinary Portland Cement Specification
Clause 4: Chemical Requirements, Al2O3/SiO2 Ratio Limits for OPC
- cited in 1 question
ASTM C618 -- Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete
Table 1: Chemical Requirements -- Class C (SAF >= 50%%) and Class F (SAF >= 70%%)
How our mocks are built
Questions are written and edited by the ForensicSpot team and cited from peer-reviewed forensic textbooks, official syllabi and primary case law. Each one is verified before publishing. Detailed explanations show after you submit, so the test stays a real test. See a mistake? Tell us.
Common questions
What does the Forensic Chemistry: Cement, Mortar and Concrete XRD Phase Analysis mock cover?+
UGC-NET Forensic Science Unit VII advanced drill covering the forensic characterisation of Portland cement systems by X-ray diffraction (XRD), SEM-EDX, FTIR, and oxide chemistry. Questions test IS 269, IS 1489, IS 12269, and IS 455 composition limits for OPC, PPC, and PSC; the four clinker phases alite (C3S, 50-70%%), belite (C2S, 15-30%%), aluminate (C3A, 5-10%%), and ferrite (C4AF, 5-15%%); hydration products CSH gel (Ca/Si approximately 1.7), portlandite (Ca(OH)2, XRD at 18.0 degrees 2-theta)
How many questions and how long is the test?+
31 multiple-choice questions, 30 minutes total. Difficulty: hard. Tier: Premium.
Who is this mock for?+
Forensic science students and aspirants who want timed, exam-style practice with explanations and verified source citations on Forensic Chemistry, NET. Useful for postgraduate entrance preparation and for BSc / MSc forensic students testing their recall under time.
Are the questions reviewed?+
Each question carries a verified source citation. Faculty review for individual questions is in progress.
Do I need an account to take this mock?+
Yes, a free ForensicSpot account is required to start a timed attempt — this lets you save progress, see per-question explanations after submission, and track your topic-level performance over time.