Question

Soalan 3 Question 3 Bezakan diantara mekanisme pemindahan beban oleh daya menegak ke (a) bawah yang dikenakan pada cerucuk geseran dengan cerucuk galas. Differentiate between load transfer mechanisms due to vertically downward force acting on a friction pile from that of a bearing pile (3 markah /marks) Tentukan beban yang boleh disokong oleh sebatang cerucuk dalam tanah (b) berpasir dwi-lapisan yang menghampari satu stratum kukuh sekiranya faktor keselamatan adalah 3.0. Dimensi cerucuk adalah 250mm x 250mm dan 15 m panjang. (Sila rujuk Lampiran S3). Determine the load that can be supported by a pile in a two-layer sandy soil overlying a firm stratum if the factor of safety is 3.0. The pile is 15 m long with a dimension of 250mm x 250mm. (Please refer to Aftachment S3). (8 markah/ marks) Data tanah: Lapisan bawah: Kedalaman = 18.0 m, Lapisan atas: Kedalaman = 22.0 m, 35 25° Untuk mpengiraan rintangan geseran: Pekali tekanan bumi, K 1.3 Sudut geseran cerucuk-tanah, 8 0.6 Soil data Upper layer Depth= 22.0 m, -25 Lower layer: Depth= 18.0 m, =35 For computation of frictional resistance: Earth pressure coefficient K 1.3 Pile-soil friction angle, 6 0.6 Dalam banyak keadaan, parameter tanah yang diperolehi dari ujian makmal akan digunakan dalam melakukan analisis geoteknik. Terangkan dua ketika bilamana anda perlu menjalankan ujian tapak untuk menentukan parameter tanah bagi melakukan analisis geoteknik. In many instances soil parameters obtained from laboratory tests will be used in carrying out geotechnical analyses. Explain two instances where you need to perform field test to determine soil parameters for the purpose of geotechnical analyses (c) (4 markah /marks Lampiran 83 (Appandbrga) 1000 800 600 400 200 100 80 60 40 NO 20 10 10 20 30 40 45 Soil friction angle, (deg) Variation of the maximum values of N nd Meyerhof, 1976) with soil fricdon angle & (after N puN

Answer 1

a Load Transro mechanism e 1 Friction pile Resistana is End bearing Pile ResistanGory at the bottom sides frpm given dlata FUFA Sand 15m B225 22m 1-3xtSxI6E22 Lower layea Sandl 35 tastth pfe sture diogrom. tem Given length ot pile Since Soit is Sand Cund Friction pile 15m acts ar SO LOad cosery ing capacty of pile xkarsr tans Eastth pesure Coetticient - -3 given r Vertial Stress at botto m of pile olepth pile friction argke S=0.6 pile c/s climension 250 mmx 250 mm of Sard is not given sina unit weight Deatable value ot Cunit ueight ot Sand a1

Loose Cand . assunme sand 16 kn Load Caoying Capadty due to friction Jxlaxorxtans 1.3x 16xI5xtan (o6x25) 1 41.8 K0/M Given that factor of atety 1 Should 1be takan as 3 Safe Load on pile -u.8 kN 3.933 k Lead bearcing apacty beasring Na due to from the 9iven table attachement (Sa) Na, Value tor sand aith 25 is afr 24 1 1 Leod Cooying Capacity clue to beaseing (GD Na 16X15X24 1 5 60 k/ Sabe fral 5160 FoS 5160-1920 17 Loodd cluets bearing

tinal Load Sately applicable on given pile for 9irens Qu CbxAo tsAs 11 1920 (0.25x0.25) 13.9333 (ux0.25x15) km 11 20+ 209 Ab 0.25 x0.25 As 4x0.25x15 7 329 KN 1-7
C) finding soil parameters by carrying field tests gives us the accurate analysis of soil than that of laboratory one.anyway we carry laboratory tests because they are easy to perform. but there are some instances where lab tests can not give accurate results for example where we need undisturbed soil parameters that is in calculating the 'sensitivity' of the soil or to calculate the shear strength of undisturbed soil sample we carry 'vane shear test' in field and another example is we can know soil parameters approximately by conducting 'cone penetration test' or 'standard penetration test' .