1.1 SYMBOLS
For the purpose of this Code of Practice the following symbols apply:
| σ’ | = | effective vertical overburden pressure |
| σv‘ | = | mean vertical effective stress (kPa) |
| β | = | shaft resistance coefficient |
| γ | = | bulk unit weight of the soil |
| γ’ | = | submerged unit weight of the soil |
| γs‘ | = | effective unit weight of the soil |
| γw | = | unit weight of water |
| nh | = | constant of horizontal subgrade reaction |
| ζcs, ζγs, ζqs | = | influence factors for shape of foundation |
| ζci, ζγi, ζqi | = | influence factors for inclination of load |
| ζcg, ζγg, ζqg | = | influence factors for ground surface |
| ζct, ζγt, ζqt | = | influence factors for tilting of foundation base |
| af | = | inclination of the base of the footing |
| f′ | = | effective angle of shearing resistance |
| τs | = | ultimate shaft friction under transient tension |
| µ | = | friction factor |
| w | = | sloping inclination in front of the footing |
| n | = | Poisson’s ratio |
| A | = | cross-section area of the pile |
| B | = | width or diameter of test plate |
| Bf | = | least dimension of footing |
| Bf‘ | = | Bf – 2eB |
| c’ | = | effective cohesion of soil |
| cc | = | temporary compression of the hammer cushion |
| cp | = | temporary compression of pile |
| cq | = | temporary compression of ground at pile toe |
| dl | = | elemental length of the pile |
| D | = | least lateral dimension of the pile |
| Df | = | depth from ground surface to the base of shallow foundation |
| Dmin | = | minimum dead load |
| e | = | coefficient of restitution |
| eB | = | eccentricity of load along B direction |
| eL | = | eccentricity of load along L direction |
| E | = | Young’s modulus of the material of the pile |
| Eh | = | efficiency of hammer |
| Es | = | Young’s modulus of soil |
| fcu | = | characteristic strength of concrete |
| fy | = | characteristic strength of steel |
| Gk | = | characteristic dead load |
| h | = | hammer drop height |
| H | = | horizontal applied load |
| Ia | = | adverse imposed load including live and soil loads |
| kp | = | ground borne vibration coefficient |
| l | = | depth of the consolidation strata |
| L | = | length of the pile in mm (For piles with rock sockets, L should |
| be measured to the centre of the rock socket. For piles without | ||
| rock sockets, L may generally be measured to the pile toe.) | ||
| Lf | = | longer dimension of footing |
| Lf‘ | = | Lf – 2eL |
| N | = | SPT N-value |
| Nav | = | average SPT N-value along pile shaft but not exceeding 40 |
| Nc, Nγ, Nq | = | general bearing capacity factors which determine the capacity |
| of a long strip footing acting on the surface of a soil in a | ||
| homogenous half-space | ||
| Nq’ | = | bearing capacity factor which determines the capacity of |
| replacement piles embedded in granular soil | ||
| NSF | = | negative skin friction |
| p | = | perimeter of the pile, or perimeter of the circumscribed |
| rectangle in the case of H-pile | ||
| P | = | vertical applied load |
| Pc | = | allowable ground-bearing capacity of the piles without wind |
| Pcw | = | allowable ground-bearing capacity of the piles with wind |
| Pn | = | design pile capacity under working load without wind |
| Pnw | = | design pile capacity under working load with wind |
| Ps | = | structural strength of the pile without wind |
| Psw | = | structural strength of the pile with wind |
| Pu | = | ultimate capacity of pile |
| q | = | overburden pressure at base level of the foundation in the |
| ground adjacent to the foundation (see Figure 2.2(a) for sloping | ||
| ground) | ||
| qa | = | allowable vertical bearing pressure |
| qb | = | allowable bearing capacity of replacement piles embedded in |
| granular soil | ||
| qo | = | effective overburden pressure at the base of the foundation, i.e. |
| qo = γs‘ Df , whereγs‘ and Df are respectively the effective unit | ||
| weight and depth of the soil that originally exists above the | ||
| base of the foundation | ||
| qu | = | ultimate bearing capacity of the granular soil |
| qub | = | ultimate end bearing resistance of large diameter bored |
| piles/barrette piles | ||
| Qk | = | characteristic imposed load |
| Qu | = | ultimate resistance against bearing capacity failure |
| r | = | slope distance of recipient from pile toe (see clause 7.2.6) |
| Ra | = | allowable anchorage resistance of the pile (see clause 5.3.3) |
| Rbc | = | allowable bearing capacity for small diameter bored pile (see |
| clause 5.4.6) | ||
| Ru | = | ultimate anchorage resistance of the pile (see clauses 5.1.6 and |
| 5.3.3) | ||
| s | = | permanent set of pile. |
| S | = | settlement measured at test load W during loading test |
| Smax | = | maximum settlement measured in loading test |
| Ua | = | uplift due to the highest anticipated groundwater table |
| Up | = | uplift due to the highest possible groundwater table |
| vres | = | resultant ppv due to pile driving |
| W | = | design pile capacity under working load without wind in kN |
| W1‘ | = | effective weight of rock or soil cone |
| W2‘ | = | effective weight of soil column above rock or soil cone |
| We | = | nominal hammer energy |
| Wh | = | weight of hammer |
| Wk | = | adverse wind load |
| Wp | = | weight of pile |
| Wp‘ | = | effective self weight of the pile |
| Wr | = | weight of pile helmet |
| Wt | = | test load for plate load test (see clause 8.2(2)(b)) |
| x | = | distance of recipient from pile measured along the ground surface |
| y | = | depth of pile toe at the time of assessing vres |
hkbuildercodeofpractice 