Novel toe driving for thin-walled piles and performance of fiberglass-reinforced polymer (FRP) pile segments

2004 ◽  
Vol 41 (2) ◽  
pp. 313-325 ◽  
Author(s):  
Mohammed Sakr ◽  
M Hesham El Naggar ◽  
Moncef Nehdi
Keyword(s):  
Large Scale ◽  
Static Load ◽  
The United States ◽  
Load Test ◽  
Scale Model ◽  
Steel Shell ◽  
Static Load Test ◽  
Cross Sectional ◽  
Self Consolidating Concrete ◽  
Reinforced Polymer

Despite the rapidly growing use of pile foundations, it is presently difficult to assure the integrity and uniformity of the cross-sectional area of cast-in-place piles when using normal concrete. Cavities and soil encroachments leading to soil pockets can jeopardize their load-bearing capacity. Moreover, corrosion in reinforced concrete and steel shell piles has been very costly, exceeding US$2 billion in annual repair costs in the United States alone. To address these two challenges, extensive research has been underway at the University of Western Ontario to develop novel technology for the construction of piles. Self-consolidating concrete (SCC), a material that flows under gravity and assures the integrity of piles, is cast into fiberglass-reinforced polymer (FRP) tubes that provide corrosion-resistant reinforcement. A toe driving technique was developed to install the empty FRP shells into the soil, and SCC is subsequently cast into the shells. Driving tests using this new technique were carried out on large-scale model FRP and steel pipe piles installed in dense dry sand enclosed in a pressure chamber. FRP–SCC and steel closed-end piles were also driven using conventional piling at the pile head. Static load tests were conducted on the various pile specimens under different vertical and horizontal confining pressures. The pile specimens were instrumented to investigate their dynamic behaviour under driving and their response to static compressive, uplift, and lateral loading. It is shown that the toe driving technique is very suitable for installing FRP piles in dense soils. Results from the driving tests and static load test indicate that FRP–SCC hybrid piles are a very competitive and attractive option for the deep foundations industry.Key words: FRP, self-consolidating concrete, piles, pile drivability, toe driving, axial load, uplift load, lateral load, large-scale modeling, shaft resistance, dense sand.

scholarly journals Experimental Study on the Behavior of X-Section Pile Subjected to Cyclic Axial Load in Sand

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Yiwei Lu ◽  
Hanlong Liu ◽  
Changjie Zheng ◽  
Xuanming Ding
Keyword(s):  
Axial Load ◽  
Large Scale ◽  
Cross Sectional Area ◽  
Load Test ◽  
Dynamic Responses ◽  
Scale Model ◽  
Loading Frequency ◽  
Sectional Area ◽  
Cross Sectional ◽  
Shaft Friction

X-section cast-in-place concrete pile is a new type of foundation reinforcement technique featured by the X-shaped cross-section. Compared with a traditional circular pile, an X-section pile with the same cross-sectional area has larger side resistance due to its larger cross-sectional perimeter. The behavior of static loaded X-section pile has been extensively reported, while little attention has been paid to the dynamic characteristics of X-section pile. This paper introduced a large-scale model test for an X-section pile and a circular pile with the same cross-sectional area subjected to cyclic axial load in sand. The experimental results demonstrated that cyclic axial load contributed to the degradation of shaft friction and pile head stiffness. The dynamic responses of X-section pile were determined by loading frequency and loading amplitude. Furthermore, comparative analysis between the X-section pile and the circular pile revealed that the X-section pile can improve the shaft friction and reduce the cumulative settlement under cyclic loading. Static load test was carried out prior to the vibration tests to investigate the ultimate bearing capacity of test piles. This study was expected to provide a reasonable reference for further studies on the dynamic responses of X-section piles in practical engineering.

scholarly journals First results of pipe pile static load test in small laboratory scale

2018 ◽  
Vol 251 ◽  
pp. 04038 ◽  
Author(s):  
Michal Baca ◽  
Jaroslaw Rybak
Keyword(s):  
Static Load ◽  
Axial Loading ◽  
Laboratory Scale ◽  
Load Test ◽  
Scale Model ◽  
Small Scale ◽  
Small Laboratory ◽  
Static Load Test ◽  
First Results ◽  
Load Tests

Presented laboratory testing program of tubular steel piles is a part of a bigger research program which contained static load tests in full scale and numerical simulations of conducted research. The main goal of the research is to compare static load tests with different working conditions of a shaft. The presented small scale model tests are the last part of the research. The paper contains the testing methodology description and first results of model pile axial loading. The static load tests in a small laboratory scale were conducted in a container filled with uniformly compacted medium sand (MSa). The first results of the investigation are presented in this paper, with the comparison of two pile capacities obtained for different roughness of the pile shaft (skin friction). The results are presented as load-displacement curves obtained by means of the Brinch-Hansen 80% method.

The Subsidence Analysis of Experimental Post-Tensioned Concrete Slab Model in the Course of the Static Load Test

2015 ◽  
Vol 744-746 ◽  
pp. 1556-1559
Author(s):  
Petr Mynarcik
Keyword(s):  
Large Scale ◽  
Static Load ◽  
Concrete Slab ◽  
Base Plate ◽  
Load Test ◽  
Slab Model ◽  
Static Load Test ◽  
Research Activity ◽  
Load Effect ◽  
Post Tensioned

This article presenting results of subsidence measurement on experimental post-tensioned concrete slab model during static load test. This subsidence measurement was realized on the large scale concrete slab model and brought important data for computer modeling by FEM (finite element method). The experiment simulated the load effect of the base plate of heavy rack. In the course of the static load test subsidence was measured by set of potentiometric gauges at the particular points in real time. The experiment continue on research activity focused on problematic of interaction between concrete structures and subsoil and was realized at the Faculty of Civil Engineering, VSB – Technical University of Ostrava, Czech Republic.

Scale Model Test Research on Cable Supported Barrel Vault Structure

2010 ◽  
Vol 163-167 ◽  
pp. 465-470
Author(s):  
Wen Tao Qiao ◽  
Zhi Hua Chen
Keyword(s):  
Model Test ◽  
Static Load ◽  
Single Layer ◽  
Steel Structure ◽  
Load Test ◽  
Scale Model ◽  
Static Load Test ◽  
Static Behavior ◽  
Prototype Structure ◽  
First Time

By setting cables and struts in place in the single-layer cylindrical latticed shell, a new-style prestressed spatial steel structure--cable supported barrel vault structure is constructed, the static load test research on which is carried out for the first time in this paper. Based on the prototype building, a scale model with the scale of 1:15 is designed and manufactured for the test. The research results indicate, the static behavior of the prototype structure can be reflected approximately by this scale model. The static behavior of the single-layer cylindrical latticed shell is improved significantly by adding cables and struts, i.e., the cable supported barrel vault structure is a kind of highly efficient prestressed spatial steel structure. Compared with the case of full-span load, the half-span load makes the cable supported barrel vault structure unsafer.

Research on the Effect of Injury Beams Strengthened with Carbon Fiber Reinforced Polymer (CFRP) of the Unloading Degree

2010 ◽  
Vol 163-167 ◽  
pp. 3713-3717
Author(s):  
Shao Wei Zhao ◽  
Shi Feng Fu ◽  
Zeng Zhao Xu
Keyword(s):  
Carbon Fiber ◽  
Concrete Beam ◽  
Static Load ◽  
Reinforced Concrete Beam ◽  
Load Level ◽  
Load Test ◽  
Fiber Reinforced Polymer ◽  
Carbon Fiber Reinforced Polymer ◽  
Static Load Test ◽  
Reinforced Polymer

The static load test is done on 5 concrete beams. One beam is loaded to the destruction as a contrast specimen, and the other 4 are loaded to the predetermined damage load (80kN), then unloaded to the different load level separately, keeping the load invariable, and tested the improvement in flexing resistance after structural strengthening by CFRP.The research indicates: The ultimate capabilities of the reinforced concrete beam specimens reinforced by carbon fiber sheets can increase 20.93%~39.80% compared with the specimen without CFRP.

scholarly journals Research on Bearing Characteristics of Open-Ended Pipe Piles under Static Load

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Haibao Feng ◽  
Xingke Dai ◽  
Shuiyue Chen ◽  
Jianwei Chen
Keyword(s):  
Bearing Capacity ◽  
Large Scale ◽  
Static Load ◽  
Vertical Direction ◽  
Load Test ◽  
Scale Model ◽  
Silty Clay ◽  
Single Pile ◽  
Tip Resistance ◽  
Lateral Friction

The accurate estimate of the ultimate bearing capacity of a single pile in the vertical direction is an important issue in the design of the pile foundation. This paper presents a static test on a single-pile model. The test was performed through a large-scale model casing test equipment that is independently developed. Various factors that affect the different test soil samples have been taken into account. In addition, the test has measured the pile’s internal stress and displacement through the sensors that were installed on the pile. What is more, a series of studies on the settling character of the single pile, pile lateral friction, changing nature of tip resistance, and its development with settling have been carried out. Finally, this paper analyzes the bearing capacity behavior and load transfer mechanism in the compressive static load test on the single pile in the vertical direction. The test results show that, under the same static load, the lateral friction of a pile in the sand is bigger than that in the silty clay, and with the increasing load at the pile tip, the increment speed of tip resistance in the silty clay is much faster than that in the sand, while pile’s bearing capacity in the sand is much bigger than that in the silty clay.

Sign in / Sign up

Export Citation Format

Share Document