Situ Tests of Bearing Character on Large Diameter Deep Socketed Pile in Qingdao Gulf Bridge

With the development of long-span bridge engineering and increase of load on construction, the piles which socketed in rock more than 5 diameters have been used in some bridge engineering. Based on the technique of Anchored piles method, the static load tests of large diameter and deep socketed piles had been carried out in Qingdao Gulf Bridge. The bearing characteristics of large diameter pile were analyzed, including the load displacement curves of test pile; the axial force; the relationship between side friction and displacement and the sharing ratio of side resistance and end resistance. Finally, the test results were compared with specifications, The results showed that the bearing characteristic of deep socketed piles was as same as the friction piles in this area; from the results of test the side friction of pile could be estimated lower in strongly weathering breccia area while the friction in strong- weakly weathered breccia was relatively close to the value of exploration reports. At the bottom of the pile, because the relatively displacement of pile-rock was small, the pile side resistance is relatively small. It could be seen that the estimate of bearing capacity was less than the test result, and the pile foundation was safety enough.

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Field static load tests on drilled shaft founded on or socketed into rock

Canadian Geotechnical Journal ◽

10.1139/t00-048 ◽

2000 ◽

Vol 37 (6) ◽

pp. 1283-1294 ◽

Cited By ~ 16

Author(s):

Caizhao Zhan ◽

Jian-Hua Yin

Keyword(s):

Bearing Capacity ◽

Static Load ◽

Large Diameter ◽

Load Test ◽

Drilled Shaft ◽

Test Results ◽

Static Load Test ◽

End Bearing Capacity ◽

Side Resistance ◽

Load Tests

The Mass Transit Railway Corporation proposes to construct the Tseung Kwan O Depot (TKD) within Area 86 reclamation at Tseung Kwan O as part of the Tseung Kwan O Extension. The proposed foundation for the TKD comprises about 1000 large-diameter, bored, cast in situ, drilled shafts founded on or socketed into rock. To confirm the design allowable end bearing capacity and rock socket side resistance for the drilled shaft foundations, two test piles were constructed and tested. Both test piles were instrumented with strain gauges and rod extensometers. This paper presents the static compressive load test results on both test piles. The test results indicate that an end bearing capacity of 20.8 MPa (design allowable 7.5 MPa) and rock socket side resistance 2.63 MPa (design allowable 0.75 MPa) are achieved during the pile load tests with no sign of failure.Key words: drilled shaft, static load test, end bearing capacity, rock socket, rock socket side resistance, load transfer.

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Optimization Analysis of Settlement Parameters for Postgrouting Piles in Loess Area of Shaanxi, China

Advances in Civil Engineering ◽

10.1155/2019/7085104 ◽

2019 ◽

Vol 2019 ◽

pp. 1-16 ◽

Cited By ~ 10

Author(s):

Zhijun Zhou ◽

Shanshan Zhu ◽

Xiang Kong ◽

Jiangtao Lei ◽

Tong Liu

Keyword(s):

Compression Modulus ◽

Summation Method ◽

Cone Penetration ◽

Optimization Analysis ◽

Loess Area ◽

Elastic Compression ◽

Settlement Calculation ◽

Side Resistance ◽

Load Tests ◽

The Relationship

The settlement calculation of postgrouting piles is complex and depends on the calculation method and parameters. Static load tests were conducted to compare the settlement characteristics of nongrouting and postgrouting piles, and three vital parameters in the layer-wise summation method were revised to predict the settlement of postgrouting piles. The elastic compression coefficient was deduced based on the Mindlin–Geddes method by considering the influence of the change in the pile side resistance distribution and end resistance ratio on the elastic compression after grouting. The relationship between the compression modulus and soil gravity stress and cone penetration resistance were established, respectively, using experimental data. The optimum value of the settlement empirical coefficient was determined using regional data. Finally, we used the postgrouting pile of the Wuqi–Dingbian expressway as a practical example. The results obtained from the layer-wise summation method after parametric optimization were close to the measured values. The results of this study provide reference data and guidance for the settlement calculation of postgrouting piles in this area.

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The use of science in long span bridge engineering

IABSE Symposium Report ◽

10.2749/222137813808626614 ◽

2013 ◽

Vol 101 (23) ◽

pp. 1-11

Author(s):

Robin Sham

Keyword(s):

Bridge Engineering ◽

Long Span ◽

Long Span Bridge

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Intelligent Prediction for Side Friction of Large-Diameter and Super-Long Steel Pipe Pile Based on Support Vector Machine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.747 ◽

2012 ◽

Vol 170-173 ◽

pp. 747-750 ◽

Cited By ~ 2

Author(s):

Ming Yuan Zhang ◽

Li Liang ◽

Hua Zhu Song ◽

Yan Li ◽

Wen Tao Peng

Keyword(s):

Bearing Capacity ◽

Large Diameter ◽

Steel Pipe ◽

Support Vector ◽

Engineering Project ◽

Pipe Pile ◽

Vector Machines ◽

Load Tests ◽

Side Friction ◽

Steel Pipe Pile

In recent years, more and more large-diameter and super-long steel pipe piles are applied in engineering project. But people just know little about the bearing characteristics of super-long piles as it is very difficult to study such type of super-long piles in the laboratory and the accumulated test data of super-long piles in actual projects is very few restricted by test conditions and test cost. In engineering work, design value of bearing capacity of large-diameter and super-long piles is still referred to the calculation theory of ordinary pile that cannot take into account engineering security and economic simultaneously. In this paper, SVM-Q which is an intelligent algorithm based on Support Vector Machines is developed for predicting side friction of large-diameter and super-long steel pipe pile. Result shows that the side friction of longer large-diameter and super-long steel pipe piles with similar bearing characteristics can be effectively predicted by the SVM-Q algorithm after fully learning enough side friction data samples of the limited testing piles with gradually larger length, and boundary length of super-long steel pipe pile in this actual engineering could be qualitatively judged by comparing predictive data with the measured data. This method is very meaningful for initiative predicting the bearing capacity of large-diameter and super-long steel pipe piles in the case that there is no suitable calculation method. The predictive bearing capacity also can be adopted to verify the bearing capacity of large-diameter and super-long steel pipe piles that donot be field-tested by static load tests in actual projects.

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State-of-the-art of long-span bridge engineering in China

Frontiers of Architecture and Civil Engineering in China ◽

10.1007/s11709-007-0051-x ◽

2007 ◽

Vol 1 (4) ◽

pp. 379-388 ◽

Cited By ~ 2

Author(s):

Haifan Xiang ◽

Yaojun Ge

Keyword(s):

State Of The Art ◽

Bridge Engineering ◽

Long Span ◽

Long Span Bridge

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Innovative Method for Evaluating Drilled Shaft Foundations for St. Croix River Bridge

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1633-11 ◽

1998 ◽

Vol 1633 (1) ◽

pp. 84-93

Author(s):

Michael W. O’Neill ◽

Gary J. Person

Keyword(s):

Drilled Shafts ◽

Interface Roughness ◽

Design Parameters ◽

Lateral Stiffness ◽

Test Results ◽

Side Resistance ◽

Major River ◽

Load Tests ◽

Drilled Shaft Foundations ◽

A Site

To develop design parameters for axially loaded drilled shafts for the St. Croix River Bridge, a major river crossing at Oak Park Heights, Minnesota, load tests were conducted on half-scale sockets in the primary formation, the Franconia Sandstone, at a site on the west bank of the river. The test results were analyzed by using a procedure that considered dilatancy at the shaft-sandstone interface using the known normal, lateral stiffness of the rock, and several candidate interface roughness patterns. The normal stiffness was measured by splitting a short socket vertically with an Osterberg load cell, within the Franconia formation. The interface roughness patterns were varied until the load-deformation behavior of the axial socket test was matched. The production shafts will have larger diameters and will penetrate the formation to a shallower depth than the axial test socket. The lateral stiffness therefore was scaled to account for these effects, and the analytical method was used to determine values of side resistance that should be used for designing the production shafts.

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Load-Bearing Characteristics of Large-Diameter Rock-Socketed Piles Based on Ultimate Load Tests

Advances in Materials Science and Engineering ◽

10.1155/2020/6075607 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Xueying Liu ◽

Xiaoyu Bai ◽

Mingyi Zhang ◽

Yonghong Wang ◽

Songkui Sang ◽

...

Keyword(s):

Load Transfer ◽

Large Diameter ◽

Peak Load ◽

Internal Force ◽

Pile Diameter ◽

Maximum Loading ◽

Side Resistance ◽

Load Tests ◽

Resistance Performance ◽

Ultimate Resistance

As part of a large converter project in Shandong Province, vertical static load tests and internal force tests were conducted on three large-diameter rock-socketed piles, their load transfer mechanism was clarified, and the ultimate side resistance and ultimate resistance performance characteristics of the rock-socketed sections were analyzed. The test results showed that the three test piles were damaged under maximum loading, the Q-s curve exhibited a steep drop, the pile compression was around 1.2 times the pile diameter, and the bearing capacity of a single pile did not meet the design requirements. The side and end resistances of the three test piles all reached their ultimate values, but the ultimate side resistance was lower than the lower limit of the recommended value in the current technical code for building pile foundations. The end resistance under maximum loading accounted for 38.4–53.8% of the peak load, which was relatively high. By comparing it with other studies, there was no significant correlation between the coefficient of rock ultimate side resistance of the rock-socketed segment and the pile diameter of the rock-socketed segment. However, the coefficient of ultimate resistance increased gradually with the pile diameter. However, the latter correlation was not significant when the pile diameter was less than 1000 mm.

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Problematic Internet Use digunakan Ketika Kesepian pada Remaja

Jurnal Ilmiah Psyche ◽

10.33557/jpsyche.v14i1.983 ◽

2020 ◽

Vol 14 (1) ◽

pp. 45-60

Author(s):

Yashinta Yashinta ◽

Dwi Hurriyati

Keyword(s):

Internet Use ◽

Hypothesis Test ◽

Problematic Internet Use ◽

Coefficient Of Determination ◽

Test Results ◽

Research Subjects ◽

Significance Level ◽

Relationship Of ◽

The Relationship ◽

Effective Contribution

This study aims to determine the relationship of loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city. Research subjects numbered 220 people using random sampling methods. Data was collected using a 60 item problematic internet use scale and a 60 item loneliness. Realibility is generated on scale of problematic internet use of 0,955 and loneliness of 0,946.Hypothesis testing uses product moment correlation analysis techniques. Hypothesis test results showed a positive relationshif between loneliness with problematic internet use on boarding students on Silaberanti street in Siantan jaya Opposite Ulu 1 Palembang city r= 0,684 with a significance level of 0,000 (p<0,01). Loneliness in this study made an effective contribution of 46,8% to problematic internet use which can be seen from the coefficient of determination (r²) that is equel to 0,468.

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