Geotechnical Engineering

DHARM 540 GEOTECHNICAL ENGINEERING 13.15 A retaining wall with a smooth vertical back, 4.5 m high, retains a dry cohesionless ba ...

14 .1 Introduction and Definitions The subject of bearing capacity is perhaps the most important of all the aspects of geotechni ...

DHARM 542 GEOTECHNICAL ENGINEERING Safe bearing capacity: Ultimate bearing capacity divided by the factor of safety. The factor ...

DHARM BEARING CAPACITY 543 In view of the wide variety of factors that affect bearing capacity, a systematic study of the factor ...

DHARM 544 GEOTECHNICAL ENGINEERING values in their code of practice ‘‘IS: 1904–1986 Code of practice for structural safety of Bu ...

DHARM BEARING CAPACITY 545 Note 1. Values listed in the table are from shear consideration only. Note 2. Values are very much ro ...

DHARM 546 GEOTECHNICAL ENGINEERING (iii) The effects of many soil characteristics which are likely to influence the bearing capa ...

DHARM BEARING CAPACITY 547 Table 14.2 Schleicher’s shape coefficients or influence factors (Jumikis, 1962) Shape of Side ratio C ...

DHARM 548 GEOTECHNICAL ENGINEERING The bearing capacity may be determined from the relation between the principal stresses at fa ...

DHARM BEARING CAPACITY 549 Equation 14.7 is rewritten sometimes, to give Df , which is termed the minimum depth required for a f ...

DHARM 550 GEOTECHNICAL ENGINEERING Equating the two values of P, we get qult = 1 22 ..γγb NNφφ(^22 −+ 1 )DNf φ ...(Eq. 14.11) Th ...

DHARM BEARING CAPACITY 551 (iii) At imminent failure, it is assumed that a part AEFB, obtained by drawing GE at (45° – φ/2) with ...

DHARM 552 GEOTECHNICAL ENGINEERING Thus, the limitations and deficiencies of Rankine’s approach in respect of Eqs. 14.7 and 14.8 ...

DHARM BEARING CAPACITY 553 If φ = 0, we have qult = 4c + γDf , the same as Eq. 14.30, for pure clay. In other words, for pure cl ...

DHARM 554 GEOTECHNICAL ENGINEERING and y, with respect to the outer edge, B, of the footing may be obtained from Wilson’s chart, ...

DHARM BEARING CAPACITY 555 (ii) The Mohr-Coulomb equation for failure envelope τ = c + σ tan φ is valid for the soil, as shown i ...

DHARM 556 GEOTECHNICAL ENGINEERING (σi + qult) BC —→ or r 0 (σi + qult) Moment, M 0 , of this force about B is r 0 (σi + qult) × ...

DHARM BEARING CAPACITY 557 Thus, the corrected expression for bearing capacity is qult^ = (c + c′) cot φ (Nφeπ tan φ – 1) ...(Eq ...

DHARM 558 GEOTECHNICAL ENGINEERING Then, for φ = 0, qult = (2 + π)c = 5.14 c (vi) Prandtl’s expression, as originally derived, d ...

DHARM BEARING CAPACITY 559 Considering a unit length of the footing and the equilibrium of wedge ABC, the vertical components of ...