Laserfiche WebLink
P' P' <br />FS = auaw _ arrow =3 <br />Pa,�ar 1,034 <br />Therefore, P',dlo, = 3 x 1,039 = 3,117 kPa <br />As noted above, the gradation for the drainage layer used in Module 4 shows maximum <br />grain size of 9.5 mm. Since the gravel particles are next to each other in a layer and not <br />isolated, the effective protrusion height can be assumed to be half the maximum gravel <br />size; i.e., <br />H = 0.5 x 9.5 mm = 4.75 mm = 0.000475 m <br />Although rounded gravel was specified, to be conservative, assume that the gravel used is <br />sub -rounded. For sub -rounded stone, <br />MFS = 0.5 <br />For packed stones, <br />MFPD = 0.5 <br />Because waste to be placed above the geotextile is deep, maximum arching is anticipated, <br />therefore, <br />MFA = 0.25 <br />The FsCR depends on the mass per unit area of the geotextile. There is no geotextile <br />cushion, but the protrusion size is very small; assume a conservative value of 2, <br />FCR � 2 <br />Assume, a factor of safety of 1.3 for chemical and biological degradation, <br />FCBD = 1.3 <br />Substituting the above values in eq. 1, <br />or <br />3,117 = 50+0.00045 m][ 1 F1 <br />(0.000475)2 (0.5) (0.5) (0.25) (1.3) (2) <br />3,117 = 307 + (12,274)M <br />or <br />M = (3,117-307)/12,274 = 0.228 g/m2 = 0.007 ozlyd2 <br />K r , <br />Since the required M is practically equal to zero, the calculations show that the <br />geomembrane can support the proposed 241 feet of waste without a geotextile cushion. <br />Page 2 of 3 <br />N.IGEOTECHNICALWCRC&SL-20071Punture-Resistance4Nodule 4WCRC&SL_M4_Puncture-Protection.doc <br />ki <br />