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EXHIBIT 0
<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
<br /> See Sections 18012 and 1803.1, Uniform Building Code
<br /> SECTION 18.101 -SCOPE 3. Classify the soil as fine-grained if 50 percent or more of the
<br /> This standard describes a system for classifying mineral and or- test sample passes the No. 200 (75 µm) sieve.
<br /> ganomineral soils for engineering purposes based on laboratory
<br /> determination of particle-size characteristics, liquid limit and SECTION 18.106 -PROCEDURE FOR
<br /> plasticity index. C11I,SSIFlCATION OF COARSE-GRAINED SOILS
<br /> (MORE THAN 50 PERCENT RETAINED)
<br /> SECTION 18.102 -APPARATUS Select test samples from the material passing the 3-inch (76 mm)
<br /> sieve for the determination of particle-size 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 /> lowing tests and procedures: Preparation of soil samples, liquid distribution of the fraction coarser than the No. 200 (75 µm) sieve.
<br /> limit test, plastic limit test and particle-size analysis.
<br /> Classify the sample as gravel; G, if 50 percent or more of the
<br /> coarse fmdion [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 /> Sampling shall be conducted in accordance with approved meth- percent of the coarse fraction [plus No. 200 (75 µm) sieve] passes
<br /> ods for soil investigation and sampling by auger borings, for Pene- the No. 4 (75 mm) sieve.
<br /> ttation Test and Split-barrel Sampling of Soils, and for If less than 5 percent of the test sample passed the No. 200 (75
<br /> Thin-walled Tube Sampling of Soils. µm) sieve, compute the coefficient of uniformity, Cu, and coeffi-
<br /> The sample shall be carefully identified as to origin by a boring dent of curvature, CZ, as given in Formulas 18-1-1 and 18-1-2:
<br /> number and sample number in conjundioa with a job number, a C = D60 (18-1-1)
<br /> geologic stratum, a peoooogic horizon or a location description D,a
<br /> with respell to a permanent monument, a grid system or a station D 2
<br /> number and offset with respect to a stated center line. Cz = (30) (18-1-2)
<br /> D,o x D~
<br /> The sample should also be described in accordance with an ap-
<br /> proved visual-manual procedure. (A soil which is composed pri- in which Dip, D30 and D60 are the particle size diameters corre-
<br /> marily of undecayed or partially decayed organic matter and has a sponding respectively to 10, 30 and 60 percent passing on the cu-
<br /> fibrous texture, dark brown to black Dolor, and organic odor mulative particle size distribution 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 /> jetted to We classification procedures described hereafter.) sand, SW, if Cu is greater than 4 for gravel and 6 for sand, and CZ is
<br /> between 1 and 3. Classify the sample as poorly graded gravel, GP,
<br /> SECTION 18.104 -TEST SAMPLE or poorly graded sand, SP, if either the Cu 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 percent of the test sample passed the No. 200 (75
<br /> than the 3-inch (76 mm) sieve and shall be obtained as follows: µm) sieve, determine the liquid limit and the plasticity index of a
<br /> Air dry the field sample; weigh the field sample; and separate Portion of the test sample passiag the No. 40 (425 µm) sieve in ac-
<br /> the field sample into two fractions on a 3-inch (76 mm) sieve. cordance with approved methods.
<br /> Weigh the fraction retained oa the 3-inch (76 mm) sieve. Compute Classify the sample as silty gravel, GM, or silty sand, SM, if the
<br /> the percentage 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 limit versus plasticity index falls below the "A"
<br /> miz 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 /> samples. than 4.
<br /> Classify the sample as clayey gravel, GC, or clayey sand, SC, if
<br /> SECTION 18.105 -PRELIMINARY CLASSIFICATION the fines are 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. If the fines are intermediate between silt and clay, that is, the
<br /> 200 (75 µm) sieve is as follows: lot of li acct limit versus lasticit
<br /> P 9 ~ p y 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" line 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 classifies-
<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 rcent of the test sam le aased the No. 200 75 m
<br /> lion.) Pe p p ( µ )
<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 />
<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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