This glossary explains the terms that appear in our test reports, guides and service pages, from Evd and degree of compaction to RQD, air voids and fck. Each entry gives the Turkish equivalent in brackets, a short definition, the standard we work to where one applies, and a link to the guide or service page that explains more.

Acceptance values are not listed here: they come from the project specification, and our results support the decisions of the design or supervising engineer rather than replace them. For more detail, see our Knowledge Centre or contact us with your question.

A

Air content (hava içeriği)

The volume of air in compacted fresh concrete, as a percentage, measured with a pressure-type meter. It matters particularly where air entrainment is specified. Standard: TS EN 12350-7:2019. See: Concrete and aggregate testing.

Air voids, Vm (hava boşluğu)

The volume of air in compacted asphalt as a percentage of its total volume, calculated from the maximum density ρm and the bulk density ρb as (ρm − ρb) / ρm × 100, as in TS EN 12697-8. Too high a value lets water in and speeds up ageing; too low a value can lead to rutting and bleeding. See: Asphalt Coring and Hot-Mix Testing.

Asphalt core (asfalt karotu)

A cylinder cut through the full depth of the bituminous layers with a water-cooled diamond core drill once the asphalt has cooled. In the laboratory the layers are separated and tested for thickness, bulk density and, where needed, binder content and grading. Standard: TS EN 12697-27:2018. See: Asphalt coring and hot-mix asphalt testing.

Atterberg limits (Atterberg limitleri)

The water contents at which a fine soil changes state, namely the liquid limit and the plastic limit, from which the plasticity index is calculated. They are determined on the fraction finer than 0.4 mm and describe how the fines respond to water. Standard: TS EN ISO 17892-12:2018+A2:2022. See: Soil laboratory testing.

B

Binder content (bitüm içeriği)

The proportion of bitumen in an asphalt mix, as a percentage by mass of the total mix. We determine it by reflux extraction, dissolving the binder from the aggregate and calculating it from the loss in mass, and compare it with the job mix formula and its tolerance. Standard: ASTM D2172/D2172M-26. See: Asphalt Coring and Hot-Mix Testing.

Binder course (binder tabakası)

The bituminous layer between the wearing course and the bituminous base, which spreads the load and gives a regular surface for the wearing course. See: Asphalt coring and hot-mix asphalt testing.

Bituminous base (bitümlü temel tabakası)

The lowest bituminous layer, laid on the granular base; it forms the main structural part of the asphalt layers. See: Layer thickness.

Borehole (sondaj kuyusu)

A hole drilled to obtain samples, cores and test results with depth: rotary core drilling in rock, sampling and SPT in soils, and groundwater observation. It is needed where deeper layers, rock quality or groundwater must be known. See: Geotechnical drilling.

Borehole log (sondaj logu)

The record of a borehole: depth scale, layer boundaries and descriptions, sample types and depths, SPT results, core recovery and RQD for each core run, groundwater and drilling method. Soils are described to TS EN ISO 14688-1 and rock to TS EN ISO 14689. See: Geotechnical drilling.

Bulk density (kütle yoğunluğu)

The mass of an asphalt specimen or core per unit of its total volume, including the voids inside it. The procedure (dry, saturated surface-dry, sealed or by dimensions) is chosen to suit the texture of the specimen and is stated in the report. Standard: TS EN 12697-6:2020. See: Asphalt Coring and Hot-Mix Testing.

C

Carbonation (karbonatlaşma)

The reaction of carbon dioxide from the air with the cement paste, which advances inwards from the surface and lowers the alkalinity that protects reinforcement from corrosion. A carbonated surface is harder, so rebound numbers on old buildings can overstate strength. See: Rebound number.

CBR – California bearing ratio (Kaliforniya taşıma oranı)

A laboratory index of bearing capacity: a standard plunger is pushed into a compacted specimen at a constant rate, and the force at set penetrations is expressed as a percentage of standard reference forces. The test is run unsoaked or after soaking, with the swell measured during soaking. Standard: TS EN 13286-47:2021. See: Proctor, CBR and water content tests.

Compressive strength (basınç dayanımı)

The maximum load carried by a cube, cylinder or core divided by its cross-sectional area, in MPa (N/mm²). We test specimens on our 2000 kN compression machine. Standards: TS EN 12390-3:2019, TS EN 12390-4:2025 (testing machine). See: Concrete and aggregate testing.

Concrete core (beton karotu)

A cylinder drilled from a structural element with a water-cooled diamond rig, then prepared and tested for the compressive strength and density of the concrete actually in the structure. We drill diameters from Ø52 to 250 mm; about 100 mm is usual for strength testing, preferably at least three times the maximum aggregate size. Standards: TS EN 12504-1:2019, ASTM C42/C42M-20. See: Concrete coring and core strength.

Consistence class, S1–S5 (kıvam sınıfı)

The slump class of fresh concrete specified in TS EN 206, from S1 (stiffest) to S5 (most fluid), shown on the delivery note. Adding water on site to reach a higher class raises the water/cement ratio and lowers strength and durability. See: Slump.

Consistency index, Ic (kıvam indisi)

Ic = (LL − w) / PI, which places the natural water content w between the limits: Ic = 0 at the liquid limit and Ic = 1 at the plastic limit. Higher values indicate a stiffer fine soil in its natural state. See: Atterberg limits.

Cube and cylinder specimens (küp ve silindir numuneler)

Specimens cast from a sample of fresh concrete, usually 150 mm cubes or 150 × 300 mm cylinders as in TS EN 12390-1, cured in standard conditions and tested for compressive strength. They show the potential strength of the concrete as delivered, not the strength in the structure. Standards: TS EN 12390-2:2019, TS EN 12390-3:2019. See: Concrete and aggregate testing.

Curing (kür)

Keeping concrete moist and at a suitable temperature so that the cement hydrates and the concrete develops its strength and durability. Standard specimens are cured in water or in a humid room at 20 ± 2 °C; in a Cyprus summer, specimens left in the sun or stored dry give low results that are not the concrete’s fault. Standard: TS EN 12390-2:2019. See: Cube and cylinder specimens.

D

DCP – dynamic cone penetrometer (dinamik konik penetrometre)

A hand-operated probe in which an 8 kg hammer falling 575 mm drives a 60° cone into the ground; the penetration per blow gives a resistance profile with depth, layer thicknesses and an estimated CBR. A 4.6 kg hammer is used for weak soils, and extension rods reach depths of up to 2 m. Standard: ASTM D6951/D6951M-18(2023). See: Site investigation and DCP testing.

Degree of compaction (sıkışma derecesi)

The density achieved in place as a percentage of a laboratory reference density for the same material. For soils and granular layers it is the in-place dry density divided by the Proctor maximum dry density; for asphalt it is the core bulk density divided by the reference density named in the specification, such as the Marshall bulk density. Standards: ASTM D1556/D1556M-24, TS 13872:2019+T1:2026, TS EN 13286-2:2013 (reference density). See: Sand cone test and degree of compaction.

Density of fresh concrete (taze beton yoğunluğu)

The mass of compacted fresh concrete per unit volume, measured in a container of known volume, in kg/m³. A value far from the expected one can point to the wrong mix, entrapped air or poor compaction. Standard: TS EN 12350-6:2019. See: Concrete and aggregate testing.

DPI – DCP penetration index (DCP penetrasyon indeksi)

The penetration of the DCP cone per blow, in mm/blow; a change of slope in the depth profile marks a layer boundary. The appendix of ASTM D6951 gives correlations for estimating CBR, in general CBR = 292 / DPI^1.12 with separate equations for CL and CH clays, so the estimate is indicative and does not replace a laboratory CBR test. Standard: ASTM D6951/D6951M-18(2023). See: DCP.

Dry density (kuru yoğunluk)

The mass of solid particles per unit of total volume, calculated from the bulk (wet) density ρ and the water content w as ρd = ρ / (1 + w). It is the value compared with the Proctor maximum dry density. Standards: ASTM D1556/D1556M-24 (in place), TS EN ISO 17892-2:2014 (laboratory). See: Sand cone test and degree of compaction.

E

Elongation index (uzunluk indeksi)

The percentage by mass of particles whose length is more than 1.8 times the mean size of their size fraction. Standard: BS 812-105.2:1990. See: Flakiness index.

Evd – dynamic deformation modulus (dinamik deformasyon modülü)

A stiffness value in MN/m² (MPa) calculated by the light weight deflectometer from the settlement of its 300 mm plate under the load pulse of a 10 kg falling weight: the smaller the settlement, the higher the Evd. It describes the stiffness of the layer system, not its density, and the required value comes from the project specification. Standard: ASTM E2835-21(2026). See: LWD compaction control and the Evd value.

Expansive clay (şişen kil)

A clay, often containing smectite-group minerals such as montmorillonite, that swells when it takes up water and shrinks when it dries; in Cyprus, wet winters and dry summers repeat this movement every year. Light buildings, ground-bearing slabs and pavements are the most affected. See: Ground in Cyprus: Marl and Expansive Clay.

F

fck – characteristic compressive strength (karakteristik basınç dayanımı)

The strength below which 5 % of all possible strength results of the specified concrete are expected to fall, normally at 28 days; fck refers to cylinders and fck,cube to cubes. It is a statistical value defined in TS EN 206, not a minimum that every single result must exceed. See: Strength class.

Fill, controlled fill (dolgu, kontrollü dolgu)

Material placed to raise ground level or to replace unsuitable ground. Controlled fill is placed and compacted in layers to a specification, and each layer is tested before the next one goes down; old fill of unknown origin needs particular care in a site investigation. See: Sand cone test and degree of compaction.

Fines (ince madde)

Particles finer than 0.063 mm, that is, silt and clay sizes. Their quantity comes from the grading test and their nature from plasticity or methylene blue tests, because harmless rock dust and active clay behave very differently. Standard: TS EN 933-1:2012. See: MB value.

Flakiness index (yassılık indeksi)

The percentage by mass of particles whose thickness is less than 0.6 times the mean size of their size fraction. Flaky particles tend to break during compaction and weaken interlock. Standard: BS 812-105.1:1989. See: Aggregate Testing in Cyprus: Grading & LA.

G

Grading, particle size distribution (granülometri, tane boyu dağılımı)

The proportions of particles of different sizes in a soil, aggregate or asphalt mix, given as the percentage passing each sieve and plotted as a grading curve. Aggregates and clayey soils are washed over the 0.063 mm sieve, because fines stuck to coarse particles are otherwise missed. Standards: TS EN 933-1:2012 (aggregates), TS EN ISO 17892-4:2016 (soils), TS EN 12697-2:2025 (asphalt). See: Aggregate Testing in Cyprus: Grading & LA.

Groundwater level (yeraltı suyu seviyesi)

The level at which water stands in a borehole or pit. The level when water is first struck can differ from the level after it has stabilised, and levels change with the season, so the log records each reading with its time. See: Borehole log.

H

Hot-mix sample (sıcak karışım numunesi)

A representative sample of asphalt mix taken at the plant, from the lorry or at the paver while paving is under way. It is used for Marshall specimens, binder content and grading; a sample missed on the day of paving cannot be taken later. Standard: TS EN 12697-27:2018. See: Asphalt Coring and Hot-Mix Testing.

I

In-situ compressive strength (yerinde basınç dayanımı)

The compressive strength of the concrete in a structure, assessed for each test region from core results and from indirect test results calibrated against cores. It is not compared directly with the number in the strength class, and what the result means for the structure is for the structural engineer to judge. Standard: TS EN 13791:2019. See: Concrete coring and in-situ strength.

J

JMF – job mix formula (onaylı karışım dizaynı)

The approved composition of an asphalt mix for a given plant and set of materials: target grading, binder content and, usually, mixing and compaction temperatures. Production and core results are compared with it within the tolerances of the specification. See: Asphalt Coring and Hot-Mix Testing.

L

L/D ratio – length/diameter ratio (boy/çap oranı)

The ratio of the prepared core length to its diameter, which affects the measured strength: shorter cores read higher. TS EN 12504-1:2019 prefers 2:1 for comparison with cylinder strength and 1:1 for comparison with cube strength, while ASTM C42/C42M-20 corrects results of cores with a ratio of 1.75 or less. Standards: TS EN 12504-1:2019, ASTM C42/C42M-20. See: Concrete coring and in-situ strength.

Layer thickness (tabaka kalınlığı)

For asphalt, the thickness of each bituminous layer measured on cores at several points around the circumference and compared with the design thickness and tolerance. For unbound layers, the DCP profile also indicates layer thicknesses. Standard: TS EN 12697-36:2022. See: Asphalt core.

Linear shrinkage (lineer büzülme)

The reduction in length of a bar of soil paste, prepared at about its liquid limit, after oven drying, as a percentage of the original length. Read with the plasticity index it indicates a tendency to shrink and swell; it is an index test, not a measurement of swell. Standard: BS 1377-2:2022. See: Ground in Cyprus: Marl and Expansive Clay.

Liquid limit, LL or wL (likit limit)

The water content at which a fine soil passes from the plastic to the liquid state, determined with the fall cone or the Casagrande cup. The two methods do not give identical results, so the report states which one was used. Standard: TS EN ISO 17892-12:2018+A2:2022. See: Atterberg limits.

Los Angeles coefficient, LA (Los Angeles katsayısı)

A measure of the resistance of coarse aggregate to fragmentation: a specified size fraction is turned with steel balls in a drum for a set number of revolutions, and the LA coefficient is the percentage then passing the 1.6 mm sieve. The lower the value, the tougher the aggregate. Standard: TS EN 1097-2:2020. See: Aggregate Testing in Cyprus: Grading & LA.

LWD – light weight deflectometer (hafif düşen ağırlık deflektometresi)

A portable device that drops a weight onto a loading plate resting on the layer and records the plate settlement with an accelerometer in the plate, giving the Evd in about two minutes per point. We use a Zorn ZFG 3.1 with a 10 kg weight and a 300 mm plate, on unbound soils and granular layers only. Standard: ASTM E2835-21(2026). See: LWD compaction control.

M

Macrotexture depth, MTD (makro doku derinliği)

A measure of pavement surface texture: a known volume of fine glass beads is spread into a circle on the surface, and the mean texture depth is that volume divided by the area covered. It relates to surface drainage and skid resistance at higher speeds. Standard: TS EN 13036-1:2010. See: Asphalt coring and hot-mix asphalt testing.

Marl (marn)

A sedimentary material made of clay and calcium carbonate, widespread in Cyprus. When dry it can look and feel like rock, but depending on its clay content it may soften and lose much of its strength once wetted. See: Ground in Cyprus: Marl and Expansive Clay.

Marshall specimen (Marshall numunesi)

A cylindrical specimen of hot-mix asphalt, about 100 mm in diameter, compacted in a mould with an impact compactor at the number of blows and temperature set by the specification. Its bulk density is often the reference for the degree of compaction of cores. Standard: TS EN 12697-30:2019. See: Asphalt Coring and Hot-Mix Testing.

Maximum density (maksimum yoğunluk)

The density of an asphalt mix with no air voids, that is, its mass divided by the volume of aggregate and binder alone, determined with the procedures of TS EN 12697-5. Together with the bulk density it is needed to calculate air voids. See: Air voids.

Maximum dry density, MDD (maksimum kuru yoğunluk)

The highest dry density reached in the Proctor test, read at the peak of the dry density–water content curve, usually in Mg/m³. It applies only to the material and the compactive effort (standard or modified Proctor) for which it was determined. Standard: TS EN 13286-2:2013. See: Proctor, CBR and water content tests.

MB value – methylene blue value (metilen mavisi değeri)

The mass of methylene blue dye adsorbed by the 0/2 mm fraction of an aggregate, in grams per kilogram; clay minerals adsorb far more dye than rock dust. A high value signals harmful clay in the fines, and the limit comes from the specification. Standard: TS EN 933-9:2022. See: Aggregate Testing in Cyprus: Grading & LA.

N

Non-plastic, NP (plastik olmayan)

The result reported when a plastic limit cannot be determined, as is typical of silty fines and rock dust. For aggregates, a non-plastic result read together with a high methylene blue value calls for a closer look at the fines. Standard: TS EN ISO 17892-12:2018+A2:2022. See: MB value.

O

Optimum water content, OMC (optimum su içeriği)

The water content at the peak of the Proctor curve, at which the given compactive effort produces the maximum dry density. Many specifications require the field water content to stay within a range around it. Standard: TS EN 13286-2:2013. See: Proctor test.

P

Particle density (tane yoğunluğu)

The mass per unit volume of the solid particles, in Mg/m³, measured with a pycnometer for soils and on oven-dried and saturated surface-dry particles for aggregates. It is used in void calculations for soils, in concrete mix design and in asphalt volumetrics. Standards: TS EN ISO 17892-3:2016 (soils), TS EN 1097-6:2022 (aggregates), TS EN 1097-7:2022 (filler). See: Aggregate Testing in Cyprus: Grading & LA.

Plastic limit, PL or wP (plastik limit)

The lowest water content at which a fine soil can be rolled into threads about 3 mm thick without crumbling. Standard: TS EN ISO 17892-12:2018+A2:2022. See: Plasticity index.

Plasticity (plastisite)

The ability of a fine soil, mainly because of its clay minerals, to be moulded without cracking over a range of water contents. It is quantified by the Atterberg limits and used in soil classification; our technical lead’s doctoral research was on the statistical modelling of the plasticity of Cypriot clayey soils. See: Ground in Cyprus: Marl and Expansive Clay.

Plasticity chart and A-line (plastisite kartı ve A çizgisi)

Casagrande’s chart of plasticity index against liquid limit, used to classify fine soils; the A-line, PI = 0.73 (LL − 20), separates clays above it from silts below it. Specifications often quote the resulting USCS group symbols of ASTM D2487, such as CL or CH. See: Soil classification.

Plasticity index, PI or IP (plastisite indisi)

The difference between the liquid limit and the plastic limit (PI = LL − PL), that is, the range of water content over which the soil behaves plastically. A high PI is one indicator of a clay prone to volume change, read together with linear shrinkage and fines content. Standard: TS EN ISO 17892-12:2018+A2:2022. See: Soil laboratory testing.

Proctor test (Proktor deneyi)

A laboratory test in which portions of a soil are compacted in a standard mould at several water contents with a defined rammer and number of blows, giving the maximum dry density and the optimum water content. The modified Proctor test uses more energy than the standard test and gives a higher maximum dry density and a lower optimum water content on the same material. Standard: TS EN 13286-2:2013. See: Proctor, CBR and water content tests.

R

Rebar pre-scan (donatı ön taraması)

A scan with an electromagnetic cover meter before coring or rebound testing, to mark the bars and choose a point clear of reinforcement. It is not a reported cover survey, and its resolution is limited where reinforcement is congested. Standard: BS 1881-204:1988. See: Concrete coring and core strength.

Rebound number (geri sıçrama sayısı)

The reading of a rebound (Schmidt) hammer, reflecting the hardness of the concrete near the surface. It helps compare areas and choose core locations, but it estimates strength only once correlated with cores from the same structure, and carbonation can inflate it. Standard: TS EN 12504-2:2021. See: Concrete coring and in-situ strength.

Report verification (rapor doğrulama)

Every DrillTech report carries a QR code, a report number and a verification code, so anyone can check on our verification page that it is genuine and whether it is valid, revised or cancelled. The original PDF can also be checked by its digital fingerprint (SHA-256), which is calculated in your browser. See: report verification page.

RQD – rock quality designation (kaya kalitesi göstergesi)

The sum of the lengths of intact core pieces 100 mm or longer, as a percentage of the core run length, following Deere’s definition as standardised in ASTM D6032/D6032M. Breaks caused by drilling or handling are not counted as natural fractures. See: Geotechnical drilling.

S

Sand cone test (kum konisi deneyi)

A field test for in-place density: a hole is dug through a base plate into the compacted layer, the excavated material is weighed, and the volume of the hole is found from the mass of calibrated sand that fills it. With the oven-dried water content, this gives the dry density and the degree of compaction. Standards: ASTM D1556/D1556M-24, TS 13872:2019+T1:2026. See: Sand cone in-place density.

SCR – solid core recovery (sağlam karot verimi)

The length of core recovered as solid, full-diameter cylindrical pieces, as a percentage of the core run length. See: RQD.

Site investigation (zemin etüdü)

The planned field and laboratory work that establishes the ground conditions where a structure or road will be built: trial pits, boreholes, DCP tests, sampling and laboratory testing. The scope depends on the structure and the site, and the design engineer uses the results to choose the foundation. See: Site investigation and DCP testing.

Slump (çökme, slump)

A measure of the consistence of fresh concrete: a 300 mm high cone is filled with concrete and lifted, and the slump is how far the concrete settles, in mm. Only a true slump is a valid result; a sheared or collapsed slump means the test has to be repeated or does not suit that concrete. Standard: TS EN 12350-2:2019. See: Concrete and aggregate testing.

Soil classification (zemin sınıflandırması)

Assigning a soil to a group from its grading and plasticity, for example a clay of high plasticity or a silty sand, so that results from different sites can be compared. Classification on its own does not give design parameters. Standard: TS EN ISO 14688-2:2018. See: Soil laboratory testing.

Specification (şartname)

The project document that sets test methods, frequencies and acceptance limits, such as the required degree of compaction, Evd, CBR or concrete class. Limits come from the specification, not from the laboratory, and we give a statement of conformity only where it has been agreed in advance. See: How to Read and Verify a Test Report.

Splitting tensile strength of paving blocks (parke taşı yarmada çekme dayanımı)

The strength of a concrete paving block split along its longest splitting section between two loading strips, calculated with a correction for block thickness. The results for a lot are assessed against the requirements of the standard. Standard: TS 2824 EN 1338:2005+T1:2006. See: Concrete and aggregate testing.

SPT N value (SPT N değeri)

In the standard penetration test (TS EN ISO 22476-3), a 63.5 kg hammer falling 760 mm drives a split-barrel sampler into the bottom of a borehole; after a 150 mm seating drive, N is the number of blows for the next 300 mm. Where full penetration is not achieved the result is written as blows over penetration (for example 50/80 mm), and correlations from N to soil properties are indicative only. See: Geotechnical drilling.

Strength class, e.g. C25/30 (beton dayanım sınıfı)

The designation of concrete by its characteristic strengths in TS EN 206: in C25/30, 25 MPa is the characteristic cylinder strength and 30 MPa the characteristic cube strength. The cube figure is higher because of specimen shape, so single results should not be converted with a fixed factor. See: Concrete coring and in-situ strength.

Sub-base (alt temel)

The granular layer between the subgrade and the base of a pavement. Its material is checked for grading, fines and Los Angeles coefficient before use, and each layer is accepted on degree of compaction or Evd, as the specification requires. See: Aggregate Testing in Cyprus: Grading & LA.

Subgrade (taban zemini)

The natural ground or the top of the earthworks on which the pavement layers are built. Its bearing capacity, usually expressed as a CBR value, is a basic input to pavement design. See: Site investigation and DCP testing.

Swell (şişme)

In the CBR test, the increase in specimen height during soaking, as a percentage of the initial height. It shows sensitivity to wetting but is not a measurement of swelling pressure. Standard: TS EN 13286-47:2021. See: Expansive clay.

T

TCR – total core recovery (toplam karot verimi)

The total length of core recovered in a core run, intact or broken, as a percentage of the length drilled. Low recovery may reflect weak or fractured ground but also the drilling method, which matters in marl and calcarenite. See: RQD.

Test region (deney bölgesi)

A part of a structure, or a group of precast elements, whose concrete is considered to belong to the same population, so that its results are assessed together. Concrete of different classes or clearly different pours is not combined in one region. Standard: TS EN 13791:2019. See: In-situ compressive strength.

Trial pit, test pit (araştırma çukuru)

A pit dug with an excavator so that the layers can be seen, described, photographed and sampled directly. For light structures on shallow foundations it is among the most informative methods. See: Ground in Cyprus: Marl and Expansive Clay.

W

Water absorption (su emme)

The water taken up by aggregate particles after 24 hours’ immersion, as a percentage of their dry mass. High absorption means part of the mixing water or bitumen goes into the stone, so the value is needed for water corrections in concrete and for asphalt volumetrics. Standard: TS EN 1097-6:2022. See: Concrete and aggregate testing.

Water content, w (su içeriği)

The mass of water in a sample divided by the mass of its dry solids, as a percentage, found by oven drying to constant mass. It is needed to calculate dry density and to interpret Proctor results and Atterberg limits. Standards: TS EN ISO 17892-1:2014+A1:2022 (soils), TS EN 1097-5:2009 (aggregates). See: Soil laboratory testing.

Wearing course, surface course (aşınma tabakası)

The top bituminous layer, which carries traffic directly and provides a sealed, skid-resistant surface. Its thickness, compaction and, where specified, macrotexture are checked. See: Macrotexture depth.