Cramming the Specificities in Contemplating Safe Bearing Capacity for the Foundation Assessed from Borehole Samples in a Sandy-Moorum Zone

Borehole samples drilled up to a depth of 10 m provide a clear understanding whether a foundation is safe for any structure. The main objective of the present study reconnoitered the soil bearing capacity and foundation settlement characteristics using the standard penetration test (SPT) data obtained from 3 boreholes at 1 m, 2 m, and 3 m depths to correlate soil properties and deterrents, if any, created by groundwater. The methodology of the research is to collect soil samples, and ensuing subsoil analysis was performed in order to obtain concrete information to optimize the foundation system within the safe bearing capacity of soil and its allowable settlement. The scope of the work encompasses conducting detailed soil investigation from drilling logs, laboratory testing, and conducting and estimating safe bearing capacity. The result of the research aims at providing safety to the foundation from the investigations of conclusive recommendation to be adopted which would be economically feasible and structurally secured.

A Comparison Study on the Effect of Various Layered Sandy Soil Deposited on Final Settlement under Dynamic Loading

The foundation is expansion in base of column, wall or other structure in order to transmit the loads from the structure to under footing with a suitable pressure with soil property. There are two conditions to design foundation: 1. The stress is applied by footing on soil is not exceeded allowable bearing capacity ( ). 2. The foundation settlement and differential settlement are due to applied loads are not exceeding the allowable settlement that based on the type and size of structure, the nature of soil. Rigid square machine footing with dimension 200*200 mm with two types of relative density (50 and 85)% medium and dense density respectively are using in this study in different 28 models to show the effect of layered sandy soil in two configuration, medium-dense MD and dense-medium DM on the final settlement in magnitudes and behaviors under dynamics loads applying with different amplitude of loads (0.25 and 2) tons at surface with amplitude-frequency 0.5 Hz with explain the effect of reinforcements material on reduction the magnitude of settlement. The final results appeared with respect to the specified continuous pressure and the number of loading cycles, the resulting settlement from the dynamic loading increases with the increase in the dynamic pressure magnitude, the variation on densities of layered soil effect on the amount of settlement due to different loads applied...

Modeling of storage tank settlement based on the United States standards

Up to 60% of storage tanks in operation have uneven settlement of the outer bottom contour, which often leads to accidents. Russian and foreign regulatory documents have different requirements for strain limits of metal structures. There is an increasing need for harmonizing regulatory documents. The aim of this study is to theoretically justify and to assess the possibility of applying the U.S. standards for specifying the allowable settlement of storage tanks used in Russia. The allowable uneven settlement was calculated for a vertical steel tank (VST-20000) according to API-653, a standard of the American Petroleum Institute. The calculated allowable settlement levels were compared with those established by Russian standards. Based on the finite element method, the uneven settlement development process of a storage tank was modeled. Stress-strain state parameters of tank structures were obtained at the critical levels established in API-653. Relationships of maximum equivalent stresses in VST metal structures to the vertical settlement component for settlement zones of 6 to 72 m in length were determined. When the uneven settlement zone is 6 m in length, the limit state is found to be caused by 30-mm vertical settlement, while stresses in the wall exceed 330 MPa. When the uneven settlement zone is 36 m in length, stresses reach the yield point only at 100-mm vertical settlement.

Research on Petrochemical Industry with Analysis of Floating Roof Tanks under the Planar Inclined Foundation

Floating roof tanks constructed in soft foundations are susceptible to settlement deflections. The most common settlement type is planar inclination. In this paper, the FEM is used for the study of deformation shape and stress distribution of floating roof tanks which have different diameter under the planar inclined foundation. The allowable settlement values were determined. And they were compared with the current national standard. The result indicated that the finite element analysis results were greater than the allowable values set in the current national standard. The allowable values set in current national standard for floating roof tanks under the condition of planar inclined foundation are conservative. Reasonable criteria should take into account the effects of structural response to the foundation displacements.

Analysis of Influencing Factor of Super-Long Single Pile’s Effective Pile Length

Taking Clough & Duncan’s hyperbolic model as the transfer function, the influencing factor of super-long single pile’s effective pile length are analyzed. Discussed four kinds factors, which are the pile elastic modulus Ep, the external friction angle σ, the material parameters k1 and the allowable settlement Sa, effect on the effective pile length. The conclusion has some active meaning to super-long single piles’ the theoretical study and the application to engineering.

Study the Design and Analysis of Al-Shuhadah Bridge and Analysis by Using Plaxis Program of Finite Elements

This paper is a studying on the Al-Shuhadah Bridge lies in the Muthanna province south of Iraq, including the soil investigation taken from the project and analysis for the designed bridge firstly manually by using equations 1 and 2 according to the data provided, secondly by using three dimensional Plaxis program of finite elements. The settlement calculated by the above two ways is nearly similar and considered reasonable values compared with the allowable settlement according to Skempton and McDonald (1956) limitations for maximum settlement and maximum angular distortion. The bearing capacity of the bridge also calculated by using equation 3 and the value is larger than the applied load due to the effect of truck loading, while the study found that the bridge is not suitable to carry the dynamic loads due to the effect of train action; therefore, this bridge is used for the highway only and can success for this purpose.

Steel Storage Tank Shell Settlement Assessment Based on Finite Element and API Standard 653 Analyses

API Standard 653 addresses issues related to the inspection, repair, alteration and reconstruction of steel storage tanks built according to API Standard 650 or API 12C to help maintain tank integrity. Although the standard covers three types of tank settlement, namely edge, bottom and shell, this paper focuses on the assessment of shell settlement. It also provides a comparison between an analytical model based on API Standard 653 and a finite element analysis (FEA) model that replicates field operating loading and settlement conditions of storage tanks. A basis for comparison between both models was established from the maximum allowable settlement and strain values. Several scenarios were generated using actual field data collected from steel storage tanks located in Alberta to illustrate the correlation between the two models. Specific information on the storage tanks under consideration cannot be disclosed for confidentiality reasons.

Preliminary Surface Fault Assessment and Conceptual Fault Crossing Design of Proposed Gas Pipeline, South-Central Alaska

A preliminary geologic and engineering study of fault crossings along a proposed high pressure natural gas spur pipeline was conducted in 2005 for the Alaska Natural Gas Development Authority (ANGDA). The route crosses a number of faults that comprise the eastern Castle Mountain-Caribou fault system in south-central Alaska, which is known to be active within 60 miles (100 km) to the west. The route approaches the faults at mostly subparallel angles, resulting in several long coincident crossings, five of which were judged to be potentially active in this study. Maximum displacements of 7 feet (2.1 m) in both vertical and horizontal directions were conservatively estimated for each crossing based on a maximum magnitude 7.0 earthquake and 700-year return period suggested for the western Castle Mountain fault. Preliminary design permanent displacements were recommended as 2/3rds of the maximum. A conceptual buried crossing design in a sloped wall trench with a double geomembrane liner and loose granular backfill would accommodate both vertical and lateral displacements. Additional geologic studies could potentially substantiate longer return periods and lead to a reduction in the number of crossings, crossing lengths, and displacement values. If design displacements are close to allowable settlement criteria, the fault crossings could be eliminated from requiring special design.

Analysis of Stresses on Buried Natural Gas Pipeline Subjected to Ground Subsidence

This study was initiated to examine the stress and deformation characteristics of the pipelines which were subjected to various environmental conditions in order to confirm their integrity. As the part of them, this paper presents the analysis results for the effect of ground subsidence combined with main loads on buried natural gas pipelines. The ground subsidence which can occur for buried gas pipeline has been classified to the three cases. Finite element method was used to analyze the effect of ground subsidence on pipeline of 26 inch (0.660 m) and 30 inch (0.762 m) diameter used as high pressure (70 Kgf/cm2(686.4 Pascal)) main pipelines. This paper shows the result of stress analysis for the pipelines subjected to those three case ground subsidence. Comparing these results with safety criterion of KOGAS (0.9 σ y), maximum allowable settlement and loads have been calculated.