Vertical load-carrying behavior and design models for micropiles considering foundation configuration conditions

In the present study, the vertical load-carrying behavior of micropile foundations with various configuration conditions was investigated based on results from model load tests. Considered configuration conditions included micropile inclination angle, spacing of micropiles, and types of micropile foundations. The ultimate load capacity of micropiles varied with installation angle, showing an initial increase and peak followed by a gradual decrease with further increase in installation angle. The ultimate load capacity of micropiled rafts was affected by both installation angle and micropile spacing. The load-carrying mechanism of micropiles for the inclined condition was proposed based on the decomposed axial and lateral load and resistance components. Using the proposed load-carrying mechanism and test results obtained in this study, the load capacity ratio for an inclined micropile was proposed. The group effect and interaction effect factors for group micropiles and micropiled rafts were proposed, respectively, all of which can be used to estimate the load-carrying capacity of micropile foundations. Field load tests were conducted and it was seen that estimated results using the proposed method were in good agreement with measured results. Additional comparison with case examples from the literature also confirmed the validity of the proposed method.

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The Assessment of Using CFRP to Enhance the Behavior of High Strength Reinforced Concrete Corbels

Tikrit Journal of Engineering Sciences ◽

10.25130/tjes.28.1.08 ◽

2021 ◽

Vol 28 (1) ◽

pp. 71-83

Author(s):

Mazin Abdulrahman ◽

Shakir Salih ◽

Rusul Abduljabbar

Keyword(s):

Reinforced Concrete ◽

Ultimate Strength ◽

Load Capacity ◽

High Strength ◽

Load Carrying Capacity ◽

Test Results ◽

Ultimate Load Capacity ◽

Load Carrying ◽

Externally Bonded ◽

Effective Depth

In this research, an experimental study is conducted to investigate the behavior and strength of high strength reinforced concrete corbels externally bonded with CFRP fabric sheets and Plates with different patterns taking into account the effect of adopted variables in enhancing the ultimate strength; the effect of shear span to effective depth (a/d), configuration, type and amount of bonding. Eleven high strength reinforced corbels were cast and tested under vertical loads. Test results showed there was an improvement in the behavior and load carrying capacity of all strengthened corbels. An increasing in the ultimate strength of strengthened corbel by inclined CFRP strips reached to (92.1%) while the increasing reached to (84.21%) for using one horizontal CFRP Plates compared to un-strengthened reference specimen. Also, it can be conducted that the increase of (a/d) ratio from (0.6 to 0.8) resulted in decreasing by 21.05% in ultimate load capacity of corbels and from (0.4 to 0.6) by 31.25% and 58.69% in cracking and ultimate loads respectively Using CFRP .

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Load-Carrying Capacity of Second-Growth Douglas-Fir Stump Anchors

Western Journal of Applied Forestry ◽

10.1093/wjaf/2.3.77 ◽

1987 ◽

Vol 2 (3) ◽

pp. 77-80 ◽

Cited By ~ 3

Author(s):

Marvin R. Pyles ◽

Joan Stoupa

Keyword(s):

Carrying Capacity ◽

Deformation Behavior ◽

Ultimate Load ◽

Douglas Fir ◽

Load Carrying Capacity ◽

Test Results ◽

Tree Diameter ◽

Second Growth ◽

Load Carrying ◽

Load Tests

Abstract In order to quantify the stump anchor capacity of small second-growth Douglas-fir (Pseudotsuga menziesii [Mirb]. Franco) trees, load tests to failure were conducted on 18 stumps from trees 7 to 16.5 in dbh. The tests produced ultimate loads that varied as the square of the tree diameter. However, the ultimate load typically occurred at stump system deformations that were far in excess of that which would be considered failure of a stump anchor. A hyperbolic equation was used to describe the load-deformation behavior of each stump tested and was generalized to describe all the test results. West. J. Appl. For. 2(3):72-80, July 1987.

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Experimental and Numerical Investigation on the Load Carrying Behavior of Large Ship Windows

Volume 4A: Structures, Safety and Reliability ◽

10.1115/omae2014-23803 ◽

2014 ◽

Author(s):

Wolfgang Fricke ◽

Bjarne Gerlach ◽

Matthias Guiard

Keyword(s):

Ultimate Load ◽

Impact Loads ◽

Test Results ◽

Lateral Loads ◽

Load Range ◽

Filled Rubber ◽

Load Carrying ◽

Drop Tests ◽

Load Tests ◽

The Impact

Aboard ships windows are exposed to static as well as dynamic loads, e.g. impact loads. Failure can lead to serious consequences. Therefore two research projects were initiated in order to analyze the load carrying behavior of windows. In addition to quasi-static ultimate load tests and drop tests with water filled rubber bags special attention is paid to the Finite Element (FE) modeling. In particular the response — stresses and deformations — to quasi-static lateral loads can be calculated with good agreement to test results. Hence FE calculations can be useful to determine and compare failure mechanisms of different window designs. An ultimate load range can be estimated by taking into account the breaking strength range of glass. A comparison between FE calculations and results of the impact tests showed that these are sensitive to conditions which could hardly be measured during the test, e.g. the shape of the approaching water-filled rubber bag. Varying of parameters eventually yielded that window response to impact loads can also be calculated sufficiently, at least, to evaluate different window designs. Further investigations on this topic are in progress.

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An innovation for flat traditional conventional footing

Journal of University of Shanghai for Science and Technology ◽

10.51201/jusst/21/07158 ◽

2021 ◽

Vol 23 (07) ◽

pp. 358-364

Author(s):

Aakriti Sharma ◽

◽

Dr. Prashant Garg ◽

Amandeep Singh ◽

◽

...

Keyword(s):

Ultimate Load ◽

Load Capacity ◽

Experimental Studies ◽

Failure Surface ◽

Good Method ◽

Test Results ◽

Ultimate Load Capacity ◽

Element Analysis ◽

Shell Foundation ◽

Shell Foundations

Since their inception in the 1950s, shell foundations have grown in popularity over regular ones. In this paper, the ultimate load capacities of shell foundations on clay were determined by Numerical model tests. The results were compared with those for flat foundations with the same base. The model test results were found using finite element analysis using the program PLAXIS 2D. The experimental studies indicated that the ultimate load capacity of shell footing on clay is higher than that on flat-footing and the load settlement curves were significantly modified. The shell foundation over clay can be considered a good method to decrease the resulting settlement and material consumption at different thicknesses. Also, the rupture surface of the shell upright and inverted system was significantly deeper than both normal footings. The numerical analysis helps in understanding the deformation behavior of the studied systems and identifies the failure surface of upright and inverted shell footing.

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Theoretical Analysis of Factors Affecting Ultimate Nominal Load of Reinforced Concrete Axially Loaded Short Squire Columns (Pu) Comparing use Prokon Program

Journal of Advanced Sciences and Engineering Technologies ◽

10.32441/jaset.03.02.04 ◽

2021 ◽

Vol 3 (2) ◽

pp. 37-43

Author(s):

Yasser I O Yahia ◽

Manal O Suliman ◽

Abdulrazzaq Jawish Alkherret ◽

Shehdeh Ghannam

Keyword(s):

Compressive Strength ◽

Ultimate Load ◽

Load Capacity ◽

Ultimate Load Capacity ◽

Factors Affecting ◽

Load Carrying ◽

Compressive Strength Of Concrete ◽

Nominal Load ◽

Axially Loaded ◽

Loaded Column

One of this theoretical study, parameters that affecting the ultimate load capacity of the axially loaded column are studied. The parameters such as compressive strength of concrete and steel reinforcement ratio. Throughout study a different value of each factor will be assumed. Then the nominal load-carrying capacity of axially loaded column was calculated for these different factors parameters according using the simplified methods provided in (ACI-318- 14) building code requirement for structural concrete and Prokon Program. It is observed that increasing the compressive strength of concrete result in improving the ultimate load capacity. Using compressive strength of concrete more than 40MPa which results in increasing of (Pu) from (2362kN) to(5918KN) . On other hand The total area of longitudinal reinforcement bars (AST), and the gross area of concrete section (Ag) have a significant effects also on increasing of (Pu) value but not as (Fcʹ).

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Mechanical Performance of Timber Beams Reinforced by FRP Sheets

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.1199 ◽

2013 ◽

Vol 275-277 ◽

pp. 1199-1202

Author(s):

Yan Mei Zhu ◽

Lang Li ◽

Min Hou ◽

Qing Yuan Wang

Keyword(s):

Ultimate Load ◽

Mechanical Performance ◽

Load Capacity ◽

Initial Stiffness ◽

Ultimate Load Capacity ◽

Material Defects ◽

Load Carrying ◽

Ultimate Load Carrying Capacity ◽

Load Deflection Curve ◽

Timber Beams

In order to improve the mechanical performance of timber beams, five rectangular-section beams were used in flexural test and ten for shearing. The effects of FRP types i.e. CFRP, BFRP and AFRP, layers of FRP sheets and the way FRP sheets pasted were studied. The failure pattern, load-deflection curve, strain distribution and ultimate load capacity of the specimens were analyzed. The results indicate that the ultimate load carrying capacity of beams were increased by 15.4% to 55.1% varyingly with the reinforcement of FRP, besides, the stiffness and ductility were improved also. The improvements were lower in the specimens with material defects such as the existence of knags and shrink cracks. It’s more effective to paste the FRP sheets slantingly with the angle of 45° than vertically. However, the effect on the initial stiffness is not distinct whether reinforced or not. The analysis of strain and stress distribution manifests that the plane cross-section assumption is efficient in design and calculation of FRP reinforced timber beam.

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Two important bridges protected from earthquake by extremely big sliding pendulum isolators

IABSE Congress, Christchurch 2021: Resilient technologies for sustainable infrastructure ◽

10.2749/christchurch.2021.0816 ◽

2021 ◽

Author(s):

Agostino Marioni ◽

Roberto Dalpedri ◽

Marco Banfi ◽

Carla Cai

Keyword(s):

Load Capacity ◽

Special Focus ◽

South East Asia ◽

Vertical Load ◽

Test Results ◽

Surface Type ◽

Total Length ◽

Padma River ◽

The Difference ◽

Under Construction

The Padma Bridge is a multipurpose road-rail bridge across the Padma River currently under construction in Bangladesh and is one of the most important projects in the whole south east Asia with a total length of 6150 m. The maximum design vertical load reaches 98725 kN.The Holtekamp Bridge is a steel road bridge with 2 main spans of 150 m and 2 lateral spans of 75 for a total length of 450 m. The bridge is isolated by use of sliding pendulum isolators having a maximum vertical load capacity at ULS of 54915 kN.In both cases the isolators are double sliding surface type but with a different approach about the central articulation. The paper aims to put in evidence the difference in behaviour of the 2 types of pendulum, analysing both the theoretical approach and the test results with a special focus over the adopted solution for perform the test on a device which exceed the capacity of aby existing laboratory.

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