Experiment study on bearing capacity of large-diameter long pile in large thickness backfill loess site

This paper introduced construction method for deep pile of Zishui bridge through karst region and the checking results of the pile bearing capacity. Firstly, main structure of Zishui bridge was simply introduced. Secondly, according to the special geological conditions, construction methods for bored piles in water and drilling platform were described. The discussion focused on the problem of boring and grouting in karst foundation and their solutions. Finally, to ensure that the pile capacity can meet the design requirements, load transfer method was used on the part of pile foundation to calculate the bearing capacity. Results showed that pile bearing capacity meet the requirements, and the feasibility and correctness of construction method of Zishui bridge was also verified,which provides references for the design and construction of the same civil engineering.

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Testing Study on Bearing Behavior of Belled Large-Diameter PHC Pipe Pile by NAKS (Nakabori Kakutei System) Construction Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.353-356.533 ◽

2013 ◽

Vol 353-356 ◽

pp. 533-539 ◽

Cited By ~ 2

Author(s):

Wen Xu ◽

Yu Bin Hou

Keyword(s):

Bearing Capacity ◽

Large Diameter ◽

Field Testing ◽

Construction Method ◽

Load Test ◽

Test Field ◽

Static Load Test ◽

Pipe Pile ◽

Bored Pile ◽

Bearing Behavior

Through field static load test and pile shaft axial force test, field testing study is conducted on bearing behavior of NAKS-construction-method belled large-diameter PHC pipe pile; besides, the test result is compared with that of hammering-method PHC pipe pile and bored pile with same pile length and diameter under the same site condition. The result shows that the ultimate bearing capacity of NAKS-construction-method belled large-diameter PHC pipe pile is slightly inferior to hammering-method PHC pipe pile but obviously superior to that of bored pile. Compared with traditional hammering-method pipe pile, the pile side resistance of NAKS-construction-method belled pipe pile is smaller; however, the higher toe resistance will give better play to bearing capacity of bearing stratum of pile toe; moreover, it is found that under the action of ultimate load and failure load, the maximum settlement and final settlement of NAKS-construction-method belled pipe pile tip are obviously lower than that of other test piles, which is conductive to lessening foundation settlement of upper structure.

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Experiment Study on Mechanical Characteristics Box Girder Bridge Considering Deck Pavement

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.90-93.1216 ◽

2011 ◽

Vol 90-93 ◽

pp. 1216-1219

Author(s):

Yan Zeng ◽

Guang Bin Zhang ◽

Zhi Yong Wang

Keyword(s):

Bearing Capacity ◽

Work Performance ◽

Mechanical Characteristics ◽

Load Test ◽

Experiment Study ◽

Box Girder ◽

Bonding Performance ◽

Girder Bridge ◽

Test Result ◽

Actual Stress

In order to understand the mechanical characteristics of shenqiu Zhidian Bridge considering the influence of pavement, On the basis of installing steel mesh in rigid bridge or consecution to enhance the bonding performance between the pavement and girder, the load test is conducted. According to the test result and the calculations result the bearing capacity and work performance of bridge are evaluated. The results show that in the design of bridge, by enhancing the bonding performance between the pavement and girder, considering the overlaid pavement participating in force corresponds with the actual stress structure.

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Ultimate Load Tests on Bearing Behavior of Large-Diameter Bored Piles in Weathered Rock Foundation

Advances in Civil Engineering ◽

10.1155/2020/8821428 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Xiaoyu Bai ◽

Xueying Liu ◽

Mingyi Zhang ◽

Yonghong Wang ◽

Nan Yan

Keyword(s):

Bearing Capacity ◽

Limit State ◽

Large Diameter ◽

Diameter Ratio ◽

Load Test ◽

Single Pile ◽

Rock Foundation ◽

Deformation Characteristics ◽

Lateral Resistance ◽

Bored Piles

Based on the vertical compressive static load test and pile mechanics test of three large diameter bored piles (one of the test piles was treated with postgrouting) in granite gneisses foundation, the bearing capacity, deformation characteristics, and influencing factors of the single pile under the limit state are analyzed and compared with the recommended values of survey report and the recommended values of current codes. By comparing the measured and theoretical values of pile axial force, the bearing capacity of cast-in-place pile under normal and limit conditions is analyzed. The experimental results show that the Q-s curve of large-diameter rock-socketed mud wall retaining bored pile with a length-diameter ratio of 25–33 and rock-socketed depth of 5–8 d shows a rapid growth. After grouting treatment, the ultimate compressive bearing capacity of single pile is improved, the maximum settlement is reduced by 6.6%, the rebound rate is reduced by 11.1%, and the settlement effect of controlling pile top is not significant. The bearing capacity and deformation characteristics of the three test piles are less affected by length-diameter ratio and rock-socketed depth. For postgrouting piles, the ratio of frictional resistance of rock-socketed segment and the ratio of pile lateral resistance are less affected by length-diameter ratio and rock-socketed depth, while, for postgrouting piles, the ratio of pile lateral resistance is more affected by rock-socketed depth. The pile end resistance ratio of the three test piles is significantly affected by the rock-socketed depth, whether or not the pile side postgrouting treatment is carried out.

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Experimental Study on Static Load of Large-Diameter Piles in Nonuniform Gravel Soil

Advances in Civil Engineering ◽

10.1155/2020/6291826 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Baoyun Zhao ◽

Xiaoping Wang ◽

Mijia Yang ◽

Dongyan Liu ◽

DongSheng Liu ◽

...

Keyword(s):

Bearing Capacity ◽

Pile Foundation ◽

Static Load ◽

Large Diameter ◽

Skin Resistance ◽

Geological Structure ◽

Load Test ◽

Pile Foundations ◽

Gradual Change ◽

Test Pile

With the development of tourism, the number of multistorey buildings in mountain areas is increasing gradually, and the requirements of the form and bearing capacity of foundation in landslide areas are getting more demanding than ever. In-situ testing of rock and soil mass in slope area has important practical significance for improving the stability of building foundation. Taking a project in Baishi Mountain located in southwest of China as an example, firstly, the geological structure and mechanical properties of soil are analyzed. Then, two types of pile foundations, i.e., empty-bottom pile foundations and solid-bottom pile foundations, are designed based on the characteristics of the geological structure for carrying out the static load test on pile foundation. The test results are as follows: (a) the load settlement curve (Q-S) of the empty-bottom test pile shows a steep drop, while the Q-S curve of the solid-bottom test pile shows a gradual change, showing that the end-bearing friction pile’s property and the ultimate bearing capacity of the solid-bottom pile are higher than those of the empty-bottom pile. (b) The maximum lateral friction of the four test piles is 139.158 kPa, 148.015 kPa, 150.828 kPa, and 154.956 kPa, respectively. (c) The shaft skin resistance under ultimate load is coming close to the maximum value, and the maximum values are 9.792 mm, 7.939 mm, 9.881 mm, and 14.97 mm, respectively. Research results can serve as design bases for the pile foundation of multistorey buildings located in landslide areas of Baishi Mountain in the southwest of China and also as references for the engineering application of pile foundation in similar geological fracture areas.

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