Uplift loading

Two types of test have been used to determine the load-deformation response of bolted colunm-to-base joints. The first type is used to determine the response to uplift loading and may be carried out on a stub column in a universal test machine. An image of the bolted web and flange cleat joint at... 

Anchors are special foundation elements that are designed to take uplift loads. Anchors can be added if an existing foundation lacks uplift capacity, and competent layers of soil or rock are shallow and easy to reach. Anchors, however, cannot take lateral loads and may be sheared off if combined lateral capacity is not enough. 

Type of Foundation Vertical Compressive Load (Axial) Vertical Uplift Load (Axial) Horizontal Load (Lateral) Overturning Moment (Lateral) Torsional Moment (Torsional)... 

Side resistance usually consists of friction and cohesion between the pile and the surrounding soil or rock along the shaft of a pile. Piles that derive their resistance mainly from side resistance are termed frictional piles. Most piles in clayey soil are frictional piles. Frictional piles can also take uplift loads. The maximum side resistance of a pile Qside niax an be expressed as... 

Over the years innovations in aircraft have given rise to more new plastic developments and have kept the plastics industry profits at a higher level than any other major market principally since they can meet different environmental and load conditions. Virtually all plastics have received the benefit of the aircraft industry s uplifting influence. Practically all conceivable top quality plastics are used to provide cost advantages and improvements... 

The design load, r, also produces a corner concentrated load, R, tending to uplift t e corners of the window pane equal to ... 

Bar joists have adequate lateral support to prevent the top chords of the joists from laterally buckling under the loads published in the manufacturer s load tables. For required resistance higher than the load tables or for plastic behavior of the joists, additional lateral bracing may be required. Evaluations should be based on as-built dimensions and field inspections at the elements and welds. If rebound resistance is required, additional uplift bridging may be required. 

If this newly created ocean were left undisturbed for a few hundred million years, its waters would evaporate and be transported onto the continents in the form of precipitation streams would transport their loads into it. The sediment created in this ocean would be uplifted and incorporated into the continents. Gradually, the influence of the continental debris would be felt and the pH might shift a little. Iron would be oxidized out of the ferrous silicates to make iron oxides, but the water composition would not vary a great deal. 

Both mode I (tensile) and mode II (shear) fractures are commonly generated in sedimentary rocks during burial and uplift, and it is well established that the horizontal stresses (o and a ) as a function of burial and loading alone are related to the vertical stress according to... 

Reinforcement to Resist Uplift Stresses. The wind moment creates a positive soil load on one side of the centerline, and a negative load on the opposite side. In other words, the action of the wind tends to lift the foundation on the negative side. This upward force, or uplift effect, is resisted by the weight of the concrete base itself, and by the weight of the earth fill on top of the base. It, therefore, becomes necessary to reinforce the top of the base to resist the resulting negative bending moment. 

Tray supports must prevent trays from being lifted by upflowing vapor. Trays are usually designed to withstand an uplift pressure of about three times the tray pressure drop at maximum vapor and liquid loads (49) or 0.25 psi (107) (normally, whichever is larger). 

Isostatic rebound 1) The unloading effect of melting and retreating ice sheets on the Earth s mantle and crust, resulting in local/regional land uplift. 2) A regional increase in Earth surface elevation due to removal of a large load of ice, rock, sediments, or ocean or lake water. 

Longitudinal load If Q > Ql. then no uplift occurs, and the minimum number and size of anchor bolts should be used. 

Transverse load This metliod of determining uplift and overturning is determined from Ref 21 (see Figure 3-57). 

Axial load plus bending, load condition l,full compression, uplift, e <... 

This chapter is organized into sections on loadings, pile structures, gravity platforms, anchor uplift capacity, jack-up platforms, and hydraulic filled islands. 

Because of wind suction loads the outer layer will be lifted up, stressed and strained. Sag of the outer foil layer will increase about A/ol- Caused by the uplifting of the outer layer, the volume of the cushion will increase. According to the third gas law of Boyle-Mariotte the internal pressure must be reduced. Because of the decrease in internal pressure the difference in pressure at the inner foil layer will be reduced. Therefore, the inner layer will be discharged and the sag will decrease about A/n,. 

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