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EXHIBIT D
<br /> UNIFORM BUILDING CODE STANDARD 18-1
<br /> SOILS CLASSIFICATION
<br /> Based on Standard Method D 2487-69 of the American Society for Testing and Materials.
<br /> Extracted, with permission, from the Annual Book of ASTM Standards, copyright American Society for
<br /> Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428
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<br /> ~ ; See Sections 18012 and 1803.1, Uniform Building Code
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<br /> i , I SECTION 18.101 -SCOPE 3. Classify the soil as 5ne grained if 50 percent or more of the
<br /> test sample passcs.the No. Z00 (75 µm) sieve.
<br /> This standard dcscribas a system for dassifying mineral and or-
<br /> g$rtomineral soils for eagineeriag purposes based on laboratory '
<br /> d~tcrmination of partide~ru charadcristics, liquid limit and SECTION 18.106 -PROCEDURE FOR
<br /> plasticity index. CLASSIFICATION OF COARSE-GRAINED SOILS
<br /> (MORE THAN 50 PERCENT RETAINED)
<br /> ~ SECTION 18.102 -APPARATUS Select test samples fiom the material passing the 3-inch (76 mm)
<br /> sieve for the determination of particle-siu characteristics, liquid
<br /> Apparatus of an approved type shall be used to perform the fol- limit and plasticity index. Determine the cumulative particle-size
<br /> lo',wing tests and procedures: Preparation of soil samples, liquid distnbution of the fradioa coarser than the No. 200 (75 µm) sieve.
<br /> li~rrit test, plastic limit test aad particle-size analysis. Q~i{y the sample as graved G, if 50 percent or more of the
<br /> coarse fraction [plus No. 200 (75 µm) sieve] is retained on the No.
<br /> SECTION 18.103 - SAMPLING 4 (4.75 mm) sieve. Classify the sample as sand S, if more than 50
<br /> Srimpling shall be conducted in accordance with approved meth- percent of the coarse fraction [plus No. 200 (75 µm) sieve) passes
<br /> ods for sort inv on and lrn b a er ~ No. 4 (75 mm) sieve.
<br /> estigati lamp ' g y ug borings, for Pene-
<br /> triition Test and Split-barrel $ampling of Soils, and for If less than 5 percent of the test sample passed the No. 200 {75
<br /> ~ ( Thin-walled'Itirbe Sampling of Soils. µm) sieve, compute the ccei~icieat of uniformity, Ck, aad cceffi-
<br /> cient of curvature, Cr, as given in Formulas 18-1-1 and 18-1-2:
<br /> 'Ihe sagrple shall be carefully ideatified as to origin by a boring
<br /> number and sample nmmbcr in oonjundioa with a job number, a C„ = D60 (18-1-1)
<br /> gaologic stratum, a pedologic horizon or a location description Dro
<br /> with respect to a:permanent monmment, a grid system or a station (Da>)Z
<br /> nuknber and offset with r to a stated center line. C= _ (18-1-2)
<br /> The sample should also be descnbcd in accordanoe'with an ap- Dro x D~
<br /> proved visual-manual procedure. (A soil which is composed pri- in which Dtp, D30 and D60 are the particle size diameters corre-
<br /> warily of underayed or partially decayed organic matter aad has a spending respectively to 10, 30 and ti0 percent passing on the cu-
<br /> ~ 5brous texture, dark brown to black color, and organic odor mulatrve partrcle size distnbution curve.
<br /> should be designated as a highly organic soil, PT, and not sub- Classify the sample as well-graded gravel, GW, orwell=graded
<br /> )ceded to the classification procedural described hereafter.) sand, SW, if C„ is greater than 4 for gravel and 6 for sand, and Cz is
<br /> betwcen 1 and 3. Classify the sample as poorly graded grave(, GP,
<br /> SECTION 18.104 -TEST SAMPLE or poorly graded sand, SP, if either the ~ or the CZ criteria for
<br /> well-graded soils are not satisfied.
<br /> ~ Test samples shall represent that portion of the field sample finer if more than 12 pcrceai of the test sample passed the No. 200 (75
<br /> than the 3-inch (7ti mm) sieve and shall be obtained as follows: µm) sieve, determine the liquid limit and the plasticity index of a
<br /> rAir dry the field sample; weigh the field sample; and separate Portion of the test sample passing the No. 40 (425 µm) sieve in ac-
<br /> the field sample into two fractions on a 3-inch (76 mm) sieve. ~rdance with approved methods.
<br /> We)gh the 5acxioo retained on the 3-inch (7ti nun) sieve. Compute Classify the sample as silty gravel, GM, or silty sand, SM, if the
<br /> the,pctcentage of plus 3-inch (76 mm) material in the field sample results of the limits tests show that the fines are silty, that is, the
<br /> and note this percentage as auxiliary information. Thoroughly plot of the liquid lirnit'versus plasticity index falls below the "A"
<br /> mix the fraction passing the 3-inch (76 mm) sieve and select test line (see Plasticity Table 18-1-A) or the plasticity index is less
<br /> sarrtpies. than 4.
<br /> Classify We sample as clayey gravel, GC, or clayey sand, SC, if
<br /> SECTION 18.105 - PRELIMINARY CLASSIFICATION the fines aze clayey, that is, the plot of liquid limit versus plasticity
<br /> PROCEDURE index falls above the "A" line and the plasticity index is greater
<br /> than 7.
<br /> Procedure for the determination of percentage finer than the No.
<br /> 200 (75 µm) sieve is as follows: If the fines are intermediate between silt and clay, that is, the
<br /> plot of liquid limit versus plasticity index falls on or practically on
<br /> 1. From the material passing the 3-inch (76 mm) sieve, select a the "A" line or falls above the "A"lint but the plasticity index is in
<br /> test sample and determine the percentage of the test sample finer the range of 4 to 7, the soil should be given a borderline classifica-
<br /> than the No. 200 (75 µm) sieve. (This step may be omitted if the lion, such as GM-GC or SM-SC.
<br /> soil can obviously be classified as fine-grained by visual inspec- If 5 to 12 percent of the test sample passed the No. 200 (75 µm)
<br /> lion.) '
<br /> sieve, the soil should be given a borderline classification based on
<br /> 2. Classify the soil as coarse-grained if more than 50 percent of both its gradation and limit test characteristics, such as GW-GC or
<br /> the test sample is retained on the No. 200 (75 µm) sieve. SP-SM. (In doubtful cases the rule is to favor the less plastic clas-
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