scholarly journals Design and Performance of Concrete Pile Strengthened with Lengthened Steel-Tube Core: Model Tests and Numerical Simulations

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Shangyu Han ◽  
Lei Yun
Keyword(s):  
Bearing Capacity ◽  
Axial Force ◽  
Mechanical Performance ◽  
Load Capacity ◽  
Steel Tube ◽  
Model Tests ◽  
Scale Model ◽  
Conventional Concrete ◽  
Concrete Piles ◽  
Concrete Pile

In order to solve the problem of insufficient bearing capacity of existing concrete piles, a type of concrete pile with an additional lengthened strengthening core is designed, by inserting the steel tube through guiding hole and pouring core concrete. To reveal the mechanical performance of the reinforced piles, scale model tests and finite element simulations were performed. The results showed that both the vertical and horizontal bearing capacity increase with the length of the stiffening core. The axial force of the enhanced core is also smaller than conventional concrete piles, and the extended core can share the axial force of the foundation pile to improve the stress distribution of the pile body. These findings point toward a useful and general method for increasing the load capacity of existing concrete piles.

scholarly journals Pile Model Tests Using Strain Gauge Technology

2015 ◽  
Vol 37 (3) ◽  
pp. 49-52 ◽  
Author(s):  
Adam Krasiński ◽  
Tomasz Kusio
Keyword(s):  
Bearing Capacity ◽  
Axial Force ◽  
Strain Gauge ◽  
Force Measurement ◽  
Ground Level ◽  
Model Tests ◽  
Scale Model ◽  
Small Scale ◽  
Pile Head ◽  
Pile Model

Abstract Ordinary pile bearing capacity tests are usually carried out to determine the relationship between load and displacement of pile head. The measurement system required in such tests consists of force transducer and three or four displacement gauges. The whole system is installed at the pile head above the ground level. This approach, however, does not give us complete information about the pile-soil interaction. We can only determine the total bearing capacity of the pile, without the knowledge of its distribution into the shaft and base resistances. Much more information can be obtained by carrying out a test of instrumented pile equipped with a system for measuring the distribution of axial force along its core. In the case of pile model tests the use of such measurement is difficult due to small scale of the model. To find a suitable solution for axial force measurement, which could be applied to small scale model piles, we had to take into account the following requirements: - a linear and stable relationship between measured and physical values, - the force measurement accuracy of about 0.1 kN, - the range of measured forces up to 30 kN, - resistance of measuring gauges against aggressive counteraction of concrete mortar and against moisture, - insensitivity to pile bending, - economical factor. These requirements can be fulfilled by strain gauge sensors if an appropriate methodology is used for test preparation (Hoffmann [1]). In this paper, we focus on some aspects of the application of strain gauge sensors for model pile tests. The efficiency of the method is proved on the examples of static load tests carried out on SDP model piles acting as single piles and in a group.

Research on Concrete-Filled Rectangular Steel Tube Stiffeners and Axial Compression Bearing Capacity

2014 ◽  
Vol 1065-1069 ◽  
pp. 1092-1096 ◽  
Author(s):  
Gao Cheng ◽  
Yong Jian Liu ◽  
Lei Jiang
Keyword(s):  
Bearing Capacity ◽  
Mechanical Performance ◽  
Compressive Load ◽  
Steel Tube ◽  
Simple Construction ◽  
The Core ◽  
Steel Bar ◽  
Stiffening Ribs ◽  
Reinforcement Measures ◽  
Core Concrete

Concrete-filled rectangular steel tube four sides restraint effect on the core concrete was weaker than the corner, which made the effect not significant. The paper studied a new kind of stiffening rib –PBL stiffener to strengthen restraint effect of concrete-filled rectangular steel tube , and evaluated its advantages compared with other stiffening ribs. 9 PBL stiffened concrete-filled rectangular steel tube columns under axial compressive load were tested. It also collected the test with other stiffened rids, such as straight ribs, binding bars, knee brace, steel reinforcement cage, steel bar stiffeners, saw tooth shaped stiffeners, stitching straight stiffeners and no rib concrete filled rectangular steel tube to compare. It evaluated increasing coefficient of bearing capacity by stiffening ribs. The results showed that: the PBL stiffeners and binding bar of concrete-filled rectangular steel tube bearing capacity was greater than other reinforcement measures by more than 20%; PBL stiffener could be a new prominent type of stiffener because of its excellent mechanical performance and simple construction.

scholarly journals The Horizontal Bearing Capacity of Composite Concrete-Filled Steel Tube Piles

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Yunxiu Dong ◽  
Zhongju Feng ◽  
Haibo Hu ◽  
Jingbin He ◽  
Qilang Zhang ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Soil Compaction ◽  
Soil Mass ◽  
Steel Tube ◽  
Continuous Increase ◽  
Concrete Filled Steel Tube ◽  
Concrete Piles ◽  
Compaction Zone ◽  
Reinforced Concrete Piles ◽  
Centrifugal Model

Steel casings (SCs) are extensively and increasingly used to stabilize the borehole wall in the construction of bridge pile foundations. Steel casings (SCs), together with reinforced concrete piles (RCPs), form composite concrete-filled steel tube piles (CCFSTPs), which differ significantly from ordinary RCPs in horizontal bearing capacity. In this study, based on the characteristics of CCFSTPs, the horizontal bearing capacity of a CCFSTP was examined through a centrifugal model test with the length of the steel casing (LSC) and the modulus of the soil mass in the steel casing soil compaction zone (ESCSC_zone) as variables. Pile-side soil resistance, load-displacement curves, and pile moment curves were obtained for the CCFSTP. The results show that increasing LSC within a range of 12 cm significantly increases the ultimate horizontal bearing capacity of the CCFSTP, and further increasing LSC beyond 12 cm produces a continuous increase in the ultimate horizontal bearing capacity of the CCFSTP but only to an insignificant extent. In addition, increasing ESCSC_zone increases the ultimate horizontal bearing capacity of the CCFSTP, but to a relatively small extent. The results of this study provide a theoretical basis and technical support for the design and construction of CCFSTPs.

Analysis the Influence of Non-Prestressed Reinforcement for Horizontal Bearing Capacity of PHC Pipe Pile

2014 ◽  
Vol 919-921 ◽  
pp. 649-653
Author(s):  
Pei Sheng Xi ◽  
Xiao Kai Sun
Keyword(s):  
Bearing Capacity ◽  
Poor Performance ◽  
Analysis Software ◽  
Element Analysis ◽  
Prestressing Steel ◽  
Concrete Piles ◽  
The Poor ◽  
Concrete Pile ◽  
Prestressed Reinforcement ◽  
Better Than

We analyze the configuration of the non-pretressed reinforcement impact on the level of bearing capacity of PHC piles to effectively solve the poor performance of the general bending of pretressed concrete pile,using ANSYS finite element analysis software,through configurating the pretressed concrete pile with appropriate amount of ordinary non-presressed reinforcement.The results of numerical calculation show that the performance of PHC pile bending has been greatly improved and the deflection and bending when cracking were significantly better than ordinary PHC pile with the confiuration of non-prestressed reinforcement. We also analyze the effect of non-prestressed reinforcement and prestressing steel when the concrete piles cracking,datd shows that prestressing steel reached stress yielding firstly.The results provide a theoretical basis of the application of precast piles in the foudation ditch support project.

scholarly journals Experimental Assessment of Performance of XCC Pile in Sand

2020 ◽  
Vol 9 (3) ◽  
pp. 4346-4351
Keyword(s):  
Load Capacity ◽  
Diameter Ratio ◽  
Scale Model ◽  
Small Scale ◽  
Lateral Capacity ◽  
Vertical Loading ◽  
Arc Distance ◽  
Concrete Pile ◽  
Uplift Load ◽  
New Type

XCC (X-Section Cast in place Concrete) pile is new type of pile developed on the basis of cast-in-place pile from the conventional circular pile and capable of resisting displacement. In this study, an attempt is made to investigate the performance of XCC Pile under different loading conditions viz., vertical loading, lateral loading and uplift loading. Experimental investigation is carried out on small scale model piles embedded in sand, by changing type of loading and distance between arc to diameter ratio of the pile. The relative density of soil, type of soil and spacing between the piles are kept constant during investigations. Ultimate capacities of piles are compared with those of conventional circular pile with same diameter and length. The results show that XCC pile with arc distance to diameter ratio equal to 0.3 provides higher vertical and lateral capacity to the extent of 45 % and 39 % respectively compared to that of conventional pile. XCC Pile with arc distance to diameter ratio equal to 0.4 provides higher uplift load capacity to the extent 29 % compared to conventional circular pile.

Supporting Effect and Economic Benefit Analysis on New Type Concrete-Filled Steel Tube Supports

2010 ◽  
Vol 160-162 ◽  
pp. 608-613
Author(s):  
Qi Wang ◽  
Bei Jiang ◽  
Shu Cai Li ◽  
Han Peng Wang ◽  
Wei Teng Li ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Economic Benefit ◽  
Mechanical Performance ◽  
Soft Rock ◽  
Jointed Rock ◽  
Steel Tube ◽  
Engineering Practice ◽  
Contrast Model ◽  
Concrete Filled Steel Tube ◽  
Relative Design

The finite element contrast model such as concrete filled steel tube support, U-steel support and hollow steel tube support were established with ANSYS software, combining with engineering practice and relative design scheme of concrete filled steel tube test, respectively analysis their influencing factors and mechanical properties such as support effect, bearing capacity and so on. The economic benefit of each support was been analysised by comprehensive comparison of the material using condition and mechanical performance. The results show that, comparing with traditional U-steel support, retractable concrete filled steel tube support is a new style support with high bearing capacity, a large variety of sizes, higher economic benefit, and hence fit to support the deep soft rock broken jointed rock mass.

Research on the Bearing Capacity of High-Strength Steel Tubular H-Joints in High-Voltage Transmission Lines

2014 ◽  
Vol 513-517 ◽  
pp. 4123-4126 ◽  
Author(s):  
Yun Xu
Keyword(s):  
Bearing Capacity ◽  
Transmission Lines ◽  
Local Buckling ◽  
Bending Moment ◽  
High Strength ◽  
Steel Tube ◽  
Scale Model ◽  
Tube Plate ◽  
Control Factors ◽  
Local Strength

The steel tube-plate joints are widely applied in tall-slender tower of transmission line engineering,but there are few studies at home and abroad. In this paper,experimental study with full-scale model and analysis based on FEM were carried out on the ultimate bearing capacity of typical h-joints , and the results showed that the bending moment was transferred to the chord from the ear-plate of a narrow area, which led to local buckling on the chord wall , so the local strength of chord is one of the most important control factors in the design of this typical joint;thus the bearing capacity can improve by enhancing the strength of steel or increasing the thickness of ear-plate. In view of the phenomenon that stress concentration is easy to emerge at the intersection of the steel tube-plate joints, some improvement measures for the connections are put forward,such as adding outer half-ring stiffening plates , adding outer-ring plates , adding inner-ring plates, and revising ear-plates to smooth the concave angle , etc.

Experimental Verification on Bearing Capacity of Concrete-Filled Steel Tube Short Columns Based on Unified Theory

2010 ◽  
Vol 163-167 ◽  
pp. 1999-2004 ◽  
Author(s):  
Jing Ji ◽  
Wen Fu Zhang ◽  
Hai Yan Sui
Keyword(s):  
Mechanical Properties ◽  
Bearing Capacity ◽  
Axial Force ◽  
Calculation Method ◽  
Steel Tube ◽  
Ultimate Bearing Capacity ◽  
Unified Theory ◽  
Concrete Filled Steel Tube ◽  
Short Columns ◽  
Load Displacement

To verify the rationality of calculation method on unified theory of concrete - filled steel tube short columns under axial force, Experimental Study on mechanical properties of the 12 concrete -filled steel tube short columns with 7 different sections under axial force is preformed. Failure process and Failure mode of them are observed, load-displacement curves are obtained, and the influence for confinement coefficient ξ to the mechanical properties of short columns under axial load is analyzed. Based on load-displacement curves, ultimate bearing capacities of them are given. By comparison for ultimate bearing capacity obtained by testing and the bearing capacity according to unified theory, the results show both are in good agreement. Calculation method on unified theory of concrete - filled steel tube is fit for calculating ultimate bearing capacity of short columns under axial force with different sections, and the results are safe and reliable.

Nonlinear Finite Element Analysis of the Bearing Capacity of a New Type of Column under Axial Load

2011 ◽  
Vol 255-260 ◽  
pp. 45-48 ◽  
Author(s):  
Ya Feng Xu ◽  
Xin Zhao ◽  
Yi Fu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Bearing Capacity ◽  
Axial Load ◽  
Load Capacity ◽  
Element Model ◽  
Steel Tube ◽  
Element Analysis ◽  
Composite Columns ◽  
Steel Ratio

Based on experimental research, the bearing performance of the new column (steel tube-reinforced concrete composite columns combination strengthened with angle steel and CFRP) has been studied in detail by finite element method. A finite element model is established based on a series of assumption. The load-displacement curves are obtained. The influence of steel ratio and thickness of CFRP layers to the bearing capacity is analyzed too. The result shows that both the steel ratio and the thickness of CFRP layers have great contribution to the axial load capacity. The finite element analysis results and theoretical analysis which are in good agreement show that simulation results are generally right.

scholarly journals The experimental study and finite element analysis of wheel - buckle scaffold

2020 ◽  
Vol 165 ◽  
pp. 06018
Author(s):  
Tan Wang ◽  
Kun Luo ◽  
Kuo Yuan ◽  
Shuai feng Yuan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Bearing Capacity ◽  
Mechanical Performance ◽  
Rapid Development ◽  
Great Influence ◽  
Steel Tube ◽  
Element Analysis ◽  
Finite Element Software ◽  
Torsional Instability

With the rapid development of the construction industry, the country has a higher demand for scaffolding engineering, so it is very necessary to develop and promote the application of wheel buckle scaffolding. Steel tube scaffold with wheel buckle has the characteristics of clear transmission and good mechanical performance. In order to study the structural performance of steel tubular scaffolding with wheel buckle, the single span three-step element frame was tested. The failure mode and ultimate bearing capacity of the frame are obtained. The finite element software Sap2000 was used to conduct 3d modeling and linear buckling analysis of scaffolds in the test. The results of experiments and finite element analysis show that the failure type of steel tubular scaffolding is the overall torsional instability failure. The connection stiffness at the joint of the diagonal brace fastener has a great influence on the wheel-buckle scaffold. The diagonal brace has obvious influence on the bearing capacity of steel tubular scaffolding body with buckles.

Sign in / Sign up

Export Citation Format

Share Document