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CELE Geotechnical Engineering — CompactionMemory Anchors

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If you keep missing Compaction items on your CELE mocks despite having read the notes, the gap is usually recall speed. Memory anchors close that gap. These Compaction mnemonics have been tuned to the kinds of triggers Professional Regulation Commission (PRC) — Board of Civil Engineering builds into CELE Geotechnical Engineering questions.

Exam context

For the Civil Engineer Licensure Examination, Professional Regulation Commission (PRC) — Board of Civil Engineering tests Geotechnical Engineering under a "Core" label, with Compaction in the 5th slot across 11 chapters. CELE candidates must clear the 70% weighted average, no sub-test below 50% cut on the 2026 paper, which draws about a meaningful share of Geotechnical Engineering questions. Date to watch: May and November 2026.

Compaction - Memory Anchors

Memory techniques transform abstract geotechnical formulas and concepts into vivid, retrievable images stored in long-term memory. Research shows that attaching new information to a strong sensory image, story, or acronym increases recall by up to 400% compared to passive re-reading. For the PRC CE Board Exam, where you must retrieve γ_dry, RC, and γ_zav formulas under pressure in minutes, these anchors act as mental shortcuts — a quick trigger floods your working memory with the full concept. Use each anchor during your review: read it once, close your eyes and replay the image, then test yourself. The goal is automatic, stress-free retrieval on exam day.

Anchors

Topic

Compaction Fundamentals

Concept

Compaction expels air (not water) to increase dry unit weight

Anchor Id

Difficulty

easy

Memory Aid

Think of compaction like packing a BAON box (lunchbox) tighter. You push the rice grains closer together — the rice is the soil solids, the air gaps between grains disappear as you press down. The moisture (ulam sauce) stays in the box. You didn't drain the box; you just removed the air pockets. The box (same volume) is now heavier because more solid rice fills it.

Anchor Type

analogy

Why It Works

The familiar Filipino lunchbox analogy converts an abstract soil-mechanics concept into a concrete, sensory-rich image. Associating 'rice grains = soil solids' and 'air pockets = expelled air' makes the distinction between compaction and consolidation (which expels water) immediately clear.

Example Usage

Question: 'What does compaction remove from soil?' Trigger the baon box. Answer: AIR is expelled. Dry unit weight rises because more solids occupy the same space.

Recall Trigger

Packing a baon box of rice — pushing out air, not draining it.

Topic

Dry Unit Weight Calculation

Concept

Formula: γ_dry = γ_moist / (1 + w)

Anchor Id

Difficulty

easy

Memory Aid

Say it as a Filipino math teacher would: 'DIVIDE by ONE PLUS W.' The acronym is 'D-O-P-W' — Dry Over Plus W. Or simply: γ_dry = γ / (1 + w). Remember it as 'you must PAY 1 plus W to GET the dry value' — like a tax: the moist weight is the gross price, (1+w) is the tax factor, and what remains after dividing is the pure dry value.

Anchor Type

mnemonic

Why It Works

The 'tax analogy' frames the formula as a real-life transaction. Students instinctively know you divide the total (gross) by the tax factor to get the net — reinforcing the division operation and the (1+w) denominator.

Example Usage

Given γ = 19.5 kN/m³, w = 12%: γ_dry = 19.5 / (1 + 0.12) = 19.5 / 1.12 = 17.41 kN/m³. Trigger: 'divide by one plus w — the tax formula.'

Recall Trigger

'Gross price ÷ tax factor = net price' → γ ÷ (1+w) = γ_dry

Topic

Proctor Test and Compaction Curve

Concept

Proctor test gives γ_d,max at OMC (bell-shaped compaction curve)

Anchor Id

Difficulty

medium

Memory Aid

Picture a MOUNT MAYON silhouette — a perfectly symmetric, bell-shaped volcano. The peak of Mount Mayon IS the OMC (the sweet spot of moisture), and the peak elevation IS γ_d,max. Too little water (dry side, left flank) = friction resists compaction. Too much water (wet side, right flank) = water pushes soil apart, reducing dry density. The volcano ALWAYS peaks at exactly one optimum point.

Anchor Type

visual_association

Why It Works

Mount Mayon is the most iconic volcano in the Philippines and is famous for its near-perfect cone shape — identical to a Proctor compaction curve. Linking the curve shape to a nationally recognized landmark creates a powerful, culturally specific visual anchor.

Example Usage

When asked to sketch a compaction curve, visualize Mayon: label left flank 'dry of optimum,' peak 'OMC / γ_d,max,' right flank 'wet of optimum.' The ZAV line sits above and to the left of the peak.

Recall Trigger

Mount Mayon's perfect cone = Proctor compaction curve. Peak = OMC and γ_d,max.

Topic

Standard vs Modified Proctor

Concept

Modified Proctor → HIGHER γ_d,max and LOWER OMC than Standard Proctor

Anchor Id

Difficulty

medium

Memory Aid

Imagine two laborers compacting a road fill. STANDARD Samuel uses a lighter hammer and fewer blows — medium effort. MODIFIED Mario uses a heavier hammer (4.54 kg vs 2.49 kg) and more blows (5 layers, 25 blows each) — maximum effort. Mario's soil reaches a HIGHER peak density (γ_d,max ↑) but needs LESS moisture to do it (OMC ↓) because the extra energy itself forces grains together, reducing dependence on water lubrication. 'More muscle = less water needed, but higher peak.'

Anchor Type

micro_story

Why It Works

Assigning distinct characters (Samuel = Standard, Mario = Modified) personalizes the comparison. The logical chain 'more energy → less water needed → lower OMC but higher γ_d,max' is embedded in the story, making both shifts memorable simultaneously.

Example Usage

Board question: 'Compare OMC and γ_d,max for Standard vs Modified Proctor.' Recall Mario vs Samuel: Modified → γ_d,max higher, OMC lower. Standard → γ_d,max lower, OMC higher.

Recall Trigger

Mario (Modified) muscles his way to a HIGHER peak with LESS water.

Topic

Relative Compaction

Concept

Formula: RC = (γ_d,field / γ_d,max) × 100%

Anchor Id

Difficulty

easy

Memory Aid

RC is your GRADE in a quiz. Your score (γ_d,field) divided by the perfect score (γ_d,max) times 100 gives your percentage grade. The professor (project specifications) requires at least 90–95% to pass. If your field dry unit weight is 17.41 and the lab max is 18.5, it's like scoring 17.41 out of 18.5 — your grade is 94.1%. Just barely passed the 90% cut but not yet 95%.

Anchor Type

analogy

Why It Works

Every Filipino student has experienced the anxiety of a quiz grade — mapping RC to a familiar academic scoring system makes the formula intuitive and emotionally anchored. The pass/fail threshold mirrors real specification requirements.

Example Usage

γ_d,field = 17.41, γ_d,max = 18.5 → RC = (17.41/18.5) × 100 = 94.1%. Passes 90% spec; fails 95% spec.

Recall Trigger

RC = your quiz score percentage. γ_d,field = your score; γ_d,max = perfect score.

Topic

Relative Compaction

Concept

Specification: RC ≥ 90–95% (modified Proctor) for fills and subgrades

Anchor Id

Difficulty

easy

Memory Aid

Remember '90-95 FILLS THE ROAD.' The sentence tells you: the range (90–95%), what it applies to (fills, roads/subgrades), and the test basis (Modified Proctor implied by 'fills the road' = highway construction uses Modified). Think: a road that is 90–95% compacted FILLS the gap between failure and perfection.

Anchor Type

mnemonic

Why It Works

The phrase combines the numerical values with their application context in a short, rhythmic sentence. Philippine infrastructure context (road fills, subgrades) makes it relevant to board exam problems.

Example Usage

Question: 'What RC is typically required for highway subgrades?' → Recall '90–95 fills the road.' Answer: RC ≥ 90–95% (Modified Proctor).

Recall Trigger

'90–95 FILLS THE ROAD' — RC requirement for fills and subgrades.

Topic

Zero-Air-Voids Line

Concept

Formula: γ_zav = G_s × γ_w / (1 + w × G_s)

Anchor Id

Difficulty

hard

Memory Aid

ZAV = 'Zero Air Voids.' For the formula, remember the phrase 'G-W over ONE-plus-WG' → G_s·γ_w / (1 + w·G_s). The structure mirrors γ_dry = γ / (1+w) but replaces the numerator with 'G times gamma_water' and the denominator's w with 'w times G.' Think of it as: 'the DRY formula UPGRADED by multiplying both numerator and denominator by G_s when you reach theoretical zero air.'

Anchor Type

mnemonic

Why It Works

Connecting ZAV's formula structure to the already-known γ_dry formula creates a relational memory — students only need to remember the 'upgrade' (multiply by G_s), not an entirely new formula. This reduces cognitive load.

Example Usage

G_s = 2.68, w = 15%, γ_w = 9.81: γ_zav = (2.68 × 9.81) / (1 + 0.15 × 2.68) = 26.29 / 1.402 = 18.75 kN/m³.

Recall Trigger

'G-W over ONE-plus-WG' — ZAV formula rhythm.

Topic

Zero-Air-Voids Line

Concept

The compaction curve always lies BELOW the ZAV line (real soil retains some air)

Anchor Id

Difficulty

medium

Memory Aid

Visualize Mount Mayon (the compaction curve) looking UP at a cloud (the ZAV line) floating above it. The cloud is ALWAYS above the peak. The volcano can never reach the cloud because real soil can never achieve 100% saturation through compaction alone — there's always some trapped air. The cloud is the theoretical limit; the volcano is reality.

Anchor Type

visual_association

Why It Works

Building on the established Mount Mayon anchor (A3) and adding a cloud above it creates a spatial hierarchy — the visual now encodes both the shape of the curve AND its relationship to the ZAV boundary in one image.

Example Usage

If a calculated γ_dry at a given w exceeds γ_zav, it's WRONG — recheck. The curve cannot pierce the cloud. Use this as a sanity check in board problems.

Recall Trigger

Mount Mayon (curve) always below the cloud (ZAV line).

Topic

Compaction Fundamentals

Concept

Compaction improves: strength ↑, settlement ↓, permeability ↓

Anchor Id

Difficulty

easy

Memory Aid

SSP — 'Soil's Super Powers' from compaction: Strength ↑, Settlement ↓, Permeability ↓. Or reverse it: remember 'compaction gives Strength and kills Settling and Seeping' → SSS: Strength goes up, Settling goes down, Seeping goes down. The three S's of compaction benefits.

Anchor Type

acronym

Why It Works

Alliteration (S-S-S) groups the three benefits under one sound, making them easy to list rapidly. The up/down arrows are attached to each S during encoding, so the direction is retrieved automatically.

Example Usage

Board question: 'What are the engineering benefits of compaction?' → Recall SSS. List: increases shear strength, reduces settlement, reduces hydraulic conductivity (permeability).

Recall Trigger

Three S's of compaction: Strength ↑, Settling ↓, Seeping ↓.

Topic

Proctor Test and Compaction Curve

Concept

Dry of optimum (left of OMC): soil is stiffer, flocculated structure, higher strength but susceptible to swell

Anchor Id

A10

Difficulty

hard

Memory Aid

Imagine molding CLAY the morning after it rained but the sun already dried the surface. The clay is stiff and crumbly — hard to press together because there's not enough moisture to lubricate the grains. You're DRY of optimum. The grains huddle in clumps (flocculated), strong but brittle — like dried bibingka that cracks when you press it. Add more water and it softens to the perfect mold-able state (OMC).

Anchor Type

micro_story

Why It Works

The bibingka analogy is culturally familiar to Filipino students. The texture change (dry/crumbly to moist/pliable) physically mirrors the transition from dry-of-optimum to OMC, creating a tactile memory.

Example Usage

Question on compaction behavior dry vs wet of optimum: Dry side → flocculated, stiff, susceptible to swell if wetted later. Wet side → dispersed, lower strength, less permeable.

Recall Trigger

Dry bibingka (dry of optimum) — stiff, flocculated, crumbly.

Topic

Proctor Test and Compaction Curve

Concept

Wet of optimum (right of OMC): dispersed structure, lower permeability, more workable for liners

Anchor Id

A11

Difficulty

hard

Memory Aid

Think of overwatered lugaw (rice porridge). Too much water makes it flow easily (dispersed, workable) but less 'solid.' For compacted clay liners (like dam cores or landfill liners), you WANT wet of optimum because the dispersed structure has lower permeability — the water-filled pores block seepage. Too much water = lower γ_dry but excellent liner. The overly watery lugaw 'seals' better but has less substance.

Anchor Type

analogy

Why It Works

The lugaw analogy gives a tangible texture to 'dispersed' and explains WHY engineers deliberately compact wet of optimum for liner applications — a practical application that is frequently tested on boards.

Example Usage

Board question: 'For a compacted clay liner, on which side of OMC should you compact?' → Wet of optimum (dispersed structure → lower hydraulic conductivity).

Recall Trigger

Overwatered lugaw = wet of optimum = dispersed = low permeability liner.

Topic

Relative Compaction

Concept

Relative compaction (RC) is for cohesive/general soils; Relative density (Dr) is for granular soils

Anchor Id

A12

Difficulty

medium

Memory Aid

RC vs Dr — 'Rich Clay, Dense Rock.' RC = Relative Compaction → used for Rich (cohesive) Clay. Dr = Relative Density → used for Dense (granular) Rock/sand. The alliterative pair 'Rich Clay — Dense Rock' locks the correct pairing of test type to soil type.

Anchor Type

mnemonic

Why It Works

Direct pairing mnemonics exploit the brain's preference for parallel structure. 'R-C = Rich Clay' and 'D-r = Dense Rock' share their initials with the formula symbols, creating a two-way retrieval link.

Example Usage

If a problem gives you e_max, e_min, e_field → use Dr (granular). If it gives γ_d,field and γ_d,max → use RC (cohesive/general).

Recall Trigger

'Rich Clay, Dense Rock' — RC for clay soils, Dr for sandy/granular soils.

Topic

Compaction Fundamentals

Concept

Compaction mechanism: mechanical energy, not hydraulic — no drainage occurs

Anchor Id

A13

Difficulty

medium

Memory Aid

COMPACTION = pressing a sponge that still has air pockets but keeping all the water inside (mechanical squeeze, air out). CONSOLIDATION = pressing a waterlogged sponge over time until water drains out (hydraulic, slow, time-dependent). Compaction is fast (field rollers in minutes), consolidation is slow (clay under load over months). Same action, different fluid expelled.

Anchor Type

analogy

Why It Works

The sponge analogy is universal and tactile. Distinguishing which fluid is expelled (air vs water) and the time scale (fast vs slow) gives two independent ways to remember the distinction — redundancy improves retention.

Example Usage

Board pitfall: never confuse compaction with consolidation. Compaction = air expelled, no drainage, quick. Consolidation = water expelled, drainage required, time-dependent.

Recall Trigger

Sponge squeeze: compaction expels air (fast), consolidation expels water (slow).

Topic

Standard vs Modified Proctor

Concept

Standard Proctor test parameters: 2.49 kg hammer, 305 mm drop, 3 layers, 25 blows/layer, 944 cm³ mold

Anchor Id

A14

Difficulty

medium

Memory Aid

Chunk the numbers as a phone number pattern: '2-3-25' — hammer is about 2 (2.49 kg), layers are 3, blows are 25. The drop height (305 mm = 30.5 cm ≈ 'one foot') gives another anchor. Mold volume 944 cm³ ≈ 'almost 1 liter.' Phone number: CALL STANDARD → dial 2-3-25 (2.49kg, 3 layers, 25 blows).

Anchor Type

chunking

Why It Works

Phone number chunking is a well-established memory strategy that reduces five separate facts to one three-digit pattern. The 'almost 1 liter' approximation for the mold also provides a quick sanity-check anchor.

Example Usage

If the board asks for Standard Proctor specifications: recall the phone number 2-3-25 → 2.49 kg, 3 layers, 25 blows. Drop ≈ 305 mm. Mold ≈ 944 cm³.

Recall Trigger

Dial STANDARD: 2-3-25 (2.49 kg, 3 layers, 25 blows/layer, ~1 ft drop, ~1 L mold).

Topic

Standard vs Modified Proctor

Concept

Modified Proctor test parameters: 4.54 kg hammer, 457 mm drop, 5 layers, 25 blows/layer, 944 cm³ mold

Anchor Id

A15

Difficulty

medium

Memory Aid

Dial MODIFIED: '4-5-25' — hammer is about 4 (4.54 kg), layers are 5, blows are 25 (same as standard). The drop is 457 mm (18 inches ≈ 'one and a half feet'). Same mold volume as Standard (944 cm³). MODIFIED = MORE (heavier hammer 4.54 vs 2.49 kg, more layers 5 vs 3, taller drop 457 vs 305 mm) — only the blows per layer stay the same.

Anchor Type

chunking

Why It Works

Building on the Standard Proctor chunking (A14), Modified becomes 'the upgraded version' — everything bigger except blows/layer. The word MORE (More layers, More mass, More drop) serves as a retrieval cue for every parameter that changes.

Example Usage

Board asks Modified Proctor parameters: 4.54 kg, 5 layers, 25 blows/layer, 457 mm drop, 944 cm³ mold. Recall: MORE in everything except blows.

Recall Trigger

Dial MODIFIED: 4-5-25. Everything MORE than Standard except blows/layer.

Topic

Proctor Test and Compaction Curve

Concept

Adding water past OMC LOWERS dry unit weight

Anchor Id

A16

Difficulty

easy

Memory Aid

Pedro is filling a palengke box with soil. He adds water drop by drop — each drop helps grains slide closer together (γ_dry rises). Then he goes PAST OMC — now the water is occupying so much space that it pushes grains APART instead of helping them pack. The water is now an intruder, not a lubricant. γ_dry drops because the same volume now has LESS solid and MORE water. 'Too much water is the enemy of density.'

Anchor Type

micro_story

Why It Works

The story arc (water helps → water hurts) builds intuitive logic rather than memorized fact. The phrase 'lubricant vs intruder' provides a two-word recall for dry-side vs wet-side behavior.

Example Usage

Board question: 'Why does dry unit weight decrease on the wet side of OMC?' → Excess water occupies void space, displacing solid particles — γ_dry falls. Recall Pedro's palengke box.

Recall Trigger

Water: lubricant before OMC (γ_dry ↑), intruder after OMC (γ_dry ↓).

Topic

Zero-Air-Voids Line

Concept

ZAV line bounds the curve from ABOVE because S = 100% is theoretically impossible through compaction

Anchor Id

A17

Difficulty

medium

Memory Aid

Rhyme to remember: 'ZAV is high, curve stays low — 100% sat you cannot go. Compact all day, compress all night — some air remains, that's always right.' The ZAV line is the SKY LIMIT — the compaction curve is the GROUND — you can jump (improve compaction) but never reach the sky (full saturation through mechanical means alone).

Anchor Type

rhyme

Why It Works

Rhymes exploit phonological memory loops in working memory, making the rule stick through rhythm. The sky/ground metaphor reinforces the spatial relationship (ZAV always above the curve) with a physical image.

Example Usage

If a computed γ_dry exceeds γ_zav at the same w, the answer is mathematically impossible — flag it as an error. ZAV is an upper bound that cannot be crossed.

Recall Trigger

Rhyme: 'ZAV is high, curve stays low.' Sky (ZAV) above, ground (curve) below.

Topic

Zero-Air-Voids Line

Concept

G_s for typical soils is approximately 2.65–2.70

Anchor Id

A18

Difficulty

easy

Memory Aid

G_s = 'God's constant for soil' — almost always 2.65 to 2.70 for quartz-dominated soil. Think of it as the Philippine average: just like the Philippine average height is reliably in a narrow range, G_s for most soils is reliably near 2.68. When a problem doesn't give G_s, assume 2.65–2.70 and proceed. '2.68 — the default Filipino soil.'

Anchor Type

analogy

Why It Works

Anchoring G_s to a cultural 'average' concept makes the number feel familiar rather than arbitrary. The phrase 'Philippine average' also signals to students that this is a default assumption value — practical exam advice embedded in the anchor.

Example Usage

Problem gives no G_s but asks for γ_zav: assume G_s = 2.68 (or 2.70 if not stated). This is standard practice in board problems.

Recall Trigger

'Default G_s = 2.68, the Philippine soil average.' Range: 2.65–2.70.

Topic

Proctor Test and Compaction Curve

Concept

Compaction curve: plotting γ_dry vs w produces a single-hump bell curve with unique peak

Anchor Id

A19

Difficulty

easy

Memory Aid

See the compaction curve as a Philippine CARABAO (water buffalo) back when viewed from the side — a single hump in the middle (OMC, γ_d,max), sloping down on both sides. The left leg (dry side) is stiffer, the right leg (wet side) is softer and flatter. The ZAV line is the fence above the carabao that it can never jump over. Plot it: x-axis is water content (%), y-axis is γ_dry (kN/m³).

Anchor Type

visual_association

Why It Works

The carabao is the Philippine national animal — a deeply familiar, culturally resonant image. Mapping the single hump to the peak of the compaction curve and the animal's posture to the curve shape creates a memorable visual that is uniquely Filipino.

Example Usage

When drawing a compaction curve on the board exam: sketch the carabao hump, label peak as γ_d,max at OMC, draw ZAV line above, label dry and wet sides.

Recall Trigger

Carabao's back hump = compaction curve peak. Fence above = ZAV line.

Topic

Relative Compaction

Concept

Relative density Dr used for granular soils: Dr = (e_max - e) / (e_max - e_min)

Anchor Id

A20

Difficulty

hard

Memory Aid

Dr formula — 'MAX minus ME, over MAX minus MIN.' Think of a leaderboard: e_max is the loosest state (worst/maximum), e is your current state (ME), e_min is the densest state (best/minimum). Dr = how far you've come from the worst, divided by the total range. Dr = 0% = loosest (e = e_max); Dr = 100% = densest (e = e_min). 'How far FROM WORST relative to the FULL RANGE.'

Anchor Type

mnemonic

Why It Works

The 'leaderboard from worst to best' framing makes the formula's numerator and denominator logically meaningful rather than arbitrary symbols. Students can re-derive the formula from the concept even if they forget the exact form.

Example Usage

e_max = 0.80, e = 0.60, e_min = 0.50: Dr = (0.80-0.60)/(0.80-0.50) = 0.20/0.30 = 66.7% (medium dense).

Recall Trigger

'MAX minus ME over MAX minus MIN' = Dr. How far from worst, over full range.

Revision Game

Dry Unit Weight (γ_dry or γ_d,max)

Clue

I am the soil parameter you MAXIMIZE in a Proctor test. I measure how dense the SOLIDS are per unit volume. What am I?

Memory Link

Anchor A2: 'Net price after removing the water tax = γ_dry = γ / (1+w)'

The Proctor Compaction Curve peak at OMC

Clue

I am the mount where γ_d,max lives. I peak at exactly one perfect moisture content. Filipino engineers know me well. What engineering concept am I?

Memory Link

Anchor A3: 'Mount Mayon silhouette = compaction curve. Peak = OMC and γ_d,max.'

Modified Proctor (Mario) and Standard Proctor (Samuel)

Clue

Mario uses more energy than Samuel, achieves a higher peak, but surprisingly needs LESS water. Who are Mario and Samuel?

Memory Link

Anchor A4: Mario (Modified) = heavier hammer, more layers → higher γ_d,max, lower OMC.

Relative Compaction (RC)

Clue

I am the percentage grade of field compaction. Engineers need me to be at least 90–95% to pass inspection. What am I?

Memory Link

Anchor A5: 'Quiz grade analogy — RC = (field score / perfect score) × 100%'

Zero-Air-Voids (ZAV) Line

Clue

I am the theoretical upper ceiling of the compaction curve. I assume 100% saturation. The curve can approach me but never touch me. Who am I?

Memory Link

Anchor A8 and A17: 'Mount Mayon (curve) always below the cloud (ZAV). ZAV is high, curve stays low.'

Relative Density (Dr)

Clue

I am used for granular soils instead of Relative Compaction. My formula involves e_max, e_min, and current void ratio e. What am I?

Memory Link

Anchor A12: 'Rich Clay → RC; Dense Rock → Dr' and Anchor A20: 'MAX minus ME over MAX minus MIN.'

Zero-Air-Voids dry unit weight (γ_zav)

Clue

My formula is G_s × γ_w / (1 + w × G_s). I tell you the dry density if no air existed in the soil at all. What am I?

Memory Link

Anchor A7: 'G-W over ONE-plus-WG' — the ZAV formula rhythm.

Optimum Moisture Content (OMC)

Clue

I am the moisture content at which a soil achieves its maximum dry unit weight during Proctor testing. Too little or too much of me reduces density. What am I?

Memory Link

Anchor A3 and A16: OMC = peak of the carabao's hump / Mount Mayon's peak. Water is lubricant before me, intruder after me.

e = void ratio (dimensionless); G_s = specific gravity of solids; γ_w = 9.81 kN/m³; γ_dry = dry unit weight (kN/m³). This links compaction results (γ_dry) back to the fundamental void ratio needed for Dr calculation or ZAV verification.

Dr < 15%: Very Loose
Dr = 15–35%: Loose
Dr = 35–65%: Medium Dense
Dr = 65–85%: Dense
Dr > 85%: Very Dense

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CELE Geotechnical Engineering — CompactionMemory Anchors

Exam context

Compaction - Memory Anchors

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