Experimental Research on the Pile-Base Post-Grouting Effects of Piles of Liao River Bridge

2011 ◽  
Vol 243-249 ◽  
pp. 2389-2394
Author(s):  
Ying Lu Diao ◽  
Guo Liang Dai ◽  
Wei Ming Gong
Keyword(s):  
Bearing Capacity ◽  
Frictional Resistance ◽  
Geological Structure ◽  
Test Results ◽  
Base Resistance ◽  
Grouting Pressure ◽  
Before And After ◽  
Load Tests ◽  
Bridge Bearing ◽  
Bearing Behavior

Static load tests were carried out with Osterberg method on 3 bored piles formed in Liao River Bridge. Bearing capacity, base resistance and frictional resistance were obtained before and after base grouting. Based on the test results, the ultimate bearing capacities of piles were increased for 14.74%~43.87%, that of pile bases were increased for 89.57% ~ 163.49% and the frictional resistances were most increased for 31.20%. The pile bearing behavior was improved. Not only base resistances were improved after grouting, but also frictional resistances were improved by bettering the characteristics of soils and interfaces between piles and soils. After grouting, pile base resistance ratio of pile bearing capacity increased, and some frictional piles changed into end-bearing frictional piles. The frictional resistance of lower pile increased more than that of upper pile after grouting. The slurry penetration height of base grouting had a certain range, which was affected by quantity of mortar intrusion, grouting technology, grouting pressure and geological structure.

scholarly journals STUDY ON REINFORCEMENT OF FABRICATED HOLLOW SLAB BRIDGE BY POLYURETHANE-CEMENT COMPOSITE (PUC)

2021 ◽  
Vol 30 (2) ◽  
Author(s):  
Kexin Zhang ◽  
Tianyu Qi ◽  
Zhimin Zhu ◽  
Xingwei Xue
Keyword(s):  
Mechanical Properties ◽  
Surface Treatment ◽  
Bearing Capacity ◽  
Failure Mode ◽  
Concrete Structures ◽  
Cement Composite ◽  
Test Results ◽  
Before And After ◽  
Load Tests ◽  
Short Time

In this paper, a new polyurethane-cement composite (PUC) material is used to reinforce a 25-year hollow slab bridge. PUC material is composed of polyurethane and cement, which has good mechanical properties. After pouring PUC material at the bottom of the hollow slabs, the traffic can be restored in a short time. Ultimate bearing capacity was discussed based on the concrete structures. The failure mode of the reinforced beam depends on the PUC material. The strengthening process includes surface treatment of concrete, formwork erection and polyurethane cement pouring. In order to verify the effectiveness of PUC reinforced bridges, load tests were carried out before and after reinforcement. The test results showed that PUC could remove the bridge load and increase the stiffness of the hollow slabs.

scholarly journals Improvement of bearing capacity of soil by using natural geotextile

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
B. Panigrahi ◽  
P. K. Pradhan
Keyword(s):  
Bearing Capacity ◽  
Single Layer ◽  
Reinforced Soil ◽  
Test Results ◽  
Increase With Increase ◽  
Optimum Placement ◽  
Soil Media ◽  
Optimum Depth ◽  
Load Tests ◽  
Materials Used

Abstract An experimental study has been carried out to improve the bearing capacity of soils by using geotextile. In the present study geojute (gunny bags) is used as geotextile, whereas sand is used as soil media. This research presents the results of laboratory load tests on model square footings supported on reinforced sand beds. A total of 32 load tests are conducted to evaluate the effects of single layer reinforcement placed below square model footings. Parameters of testing programme of the research are the depth of reinforcement, the plan area of reinforcement and the footing size. The test results indicated that the maximum gain in ultimate bearing capacity (UBC) of footings on reinforced soil (by using geojute) is found to be increased by a factor of 3.37 as compared to soil without geojute. Also, the optimum size of reinforcement is found to be 3.5B × 3.5B irrespective of the type of reinforcing materials used. The optimum placement position of geotextile is found to be 0.5B from the base of the footing. At low settlement rates, the study on the values of BCR reveals almost the same results with regard to optimum depth and size of reinforcement mentioned above. It is found that with increase in the settlement rate, BCR increases. Also, the improvement in bearing capacity is found to increase with increase in footing size.

Model Test Studies of the Vertical Bearing Behavior of Bored Piles with Breakage Defects

2012 ◽  
Vol 256-259 ◽  
pp. 65-70
Author(s):  
Cheng Hua Wang ◽  
Juan Su ◽  
Gan Wang
Keyword(s):  
Bearing Capacity ◽  
Model Test ◽  
Great Influence ◽  
Test Results ◽  
Sudden Drop ◽  
Bored Piles ◽  
Vertical Bearing ◽  
Vertical Bearing Capacity ◽  
Bearing Behavior

In order to study the vertical bearing behavior of bored piles with breakage defects, a series of methods for simulation of normal piles and broken piles in laboratory was developed and used to investigate the vertical bearing behavior of these piles. The load-settlement curves of normal piles and broken piles were measured and analyzed. The tests revealed that the upper part of a broken pile works alone as a short pile before it contact with the lower part of the pile at the end of the first sudden drop stage.The analysis of the test results showed that the position of the breakage defect has a great influence on the lost in vertical bearing capacity of the pile.

Field Plate Load Tests on Dredged Sediment Dump Pond with Cement Solidified Crust Above

2011 ◽  
Vol 255-260 ◽  
pp. 2751-2755
Author(s):  
Chun Lei Zhang ◽  
Qing Song Liu ◽  
Jin Bao Liu
Keyword(s):  
Compressive Strength ◽  
Bearing Capacity ◽  
Failure Mode ◽  
Double Layer ◽  
Unconfined Compressive Strength ◽  
Test Results ◽  
Dredged Sediment ◽  
Field Plate ◽  
Failure Angle ◽  
Load Tests

In order to improve the bearing capacity of dredged sediment dump pond for succeeding foundation reinforcement construction, upper layer was placed with a layer of cement solidified crust (CSC). For the special double layer foundation, field plate load tests were conducted to study the behaviors of failure mode, deformation and ultimate bearing capacity. Test results show the failure mode of the double layer foundation takes punch failure mode, the settlement around 10-15cm, the failure angle around 33-36 degree, the ultimate bearing capacities have a lineal relationship with the unconfined compressive strength and thickness of CSC, respectively.

The bearing capacity of rigid piles and pile groups under inclined loads in clay

1981 ◽  
Vol 18 (2) ◽  
pp. 297-300 ◽  
Author(s):  
G. G. Meyerhof
Keyword(s):  
Bearing Capacity ◽  
Ultimate Bearing Capacity ◽  
Test Results ◽  
Pile Groups ◽  
Free Standing ◽  
Previous Theory ◽  
Inclined Loads ◽  
Load Tests ◽  
Batter Piles ◽  
Piled Foundations

The ultimate bearing capacity of rigid vertical and batter piles and pile groups in clay has been determined under various inclinations of the load, varying from the vertical to horizontal directions. The results of load tests on single model piles of different lengths and inclinations and on free-standing groups and piled foundations are compared with theoretical estimates. The influence of load inclination on the bearing capacity can be represented by simple interaction relationships between the axial and normal components of the ultimate load. The effect of eccentricity of the load on the ultimate bearing capacity of pile groups is discussed on the basis of previous theory and model test results.

scholarly journals Analytical Model for the End-Bearing Capacity of Tapered Piles Using Cavity Expansion Theory

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Suman Manandhar ◽  
Noriyuki Yasufuku
Keyword(s):  
Bearing Capacity ◽  
Cavity Expansion ◽  
Test Results ◽  
End Bearing Capacity ◽  
Proposed Model ◽  
Expansion Theory ◽  
Cavity Expansion Theory ◽  
Bearing Behavior ◽  
Spherical Cavity Expansion ◽  
Real Type

On the basis of evidence from model tests on increasing the end-bearing behavior of tapered piles at the load-settlement curve, this paper proposes an analytical spherical cavity expansion theory to evaluate the end-bearing capacity. The angle of tapering is inserted in the proposed model to evaluate the end-bearing capacity. The test results of the proposed model in different types of sands and different relative densities show good effects compared to conventional straight piles. The end-bearing capacity increases with increases in the tapering angle. The paper then propounds a model for prototypes and real-type pile tests which predicts and validates to evaluate the end-bearing capacity.

scholarly journals Experimental Study of the Bearing Capacity of Stiff Clay Overlying Sand with and without Geotextile Inclusion

2021 ◽  
Vol 9 (3) ◽  
pp. 119-126
Author(s):  
Bahga Mustafa ◽  
Ahmed M. Elsharief
Keyword(s):  
Bearing Capacity ◽  
Large Strain ◽  
Bottom Layer ◽  
Test Results ◽  
Dense Sand ◽  
Theoretical Approaches ◽  
Maximum Benefit ◽  
Potential Benefits ◽  
Load Tests ◽  
Stiff Clay

The objective of this study is to investigate the potential benefits of using reinforcement inclusion to improve the bearing capacity of stiff clay over very loose to medium dense sand. Model load tests were performed on two layered systems, namely stiff clay over very loose, loose, medium dense sand with and without geotextile inclusion between the two layers and on stiff clay only. The load-settlement curves were plotted from the experimental test results, and the ultimate bearing capacity was obtained using Log – Log (L-L), Tangent (TIM), 0.1B and Hyperbolic (HYP) methods. Theoretical approaches were used to compute the ultimate bearing capacities of the tests without and with reinforcement. The test results have shown an increase in the ultimate bearing capacities due to increase in the relative densities of the bottom sand layer. The bearing capacity increased significantly with the inclusion of geotextile layer. The bearing capacity ratio (BCR) for the case of very loose sand as bottom layer was the highest compared to loose and medium dense cases. Load - settlement curve of the pure clay test plots above or is identical to the load - settlement curve of stiff clay overlying medium dense sand with geotextile layer. The maximum benefit for the geotextile inclusion was gained at large strain when the sand was very loose. The analytical methods were generally in good agreement with the experimental model test results obtained by the 0.1B method.  

Assessing ballast cleaning as a rehabilitation method for railway masonry arch bridges by dynamic load tests

2017 ◽  
Vol 232 (4) ◽  
pp. 1135-1148 ◽  
Author(s):  
Saeed Mohammadzadeh ◽  
Amin Miri ◽  
Mehrdad Nouri
Keyword(s):  
Dynamic Load ◽  
Structural Changes ◽  
Dynamic Testing ◽  
Load Testing ◽  
Test Results ◽  
Masonry Arch ◽  
Rehabilitation Programs ◽  
Before And After ◽  
Load Tests ◽  
Arch Bridges

Dynamic load testing has become a common practice for condition assessment of masonry arch bridges and lays the foundation for their rehabilitation procedures; however, additional dynamic testing after rehabilitation is rare. Carrying out dynamic load tests before and after rehabilitation programs produces valuable results with regard to the structural changes of the bridge. This paper tries to assess the effects of ballast cleaning on the performance of railway masonry arch bridges by conducting dynamic load tests before and after the rehabilitation procedure. To do so, a 70-year-old masonry arch bridge is instrumented with deflection meters and accelerometers. Dynamic load tests are carried out before and after ballast cleaning and results are compared. According to the test results, vertical deflections of different spots on the bridge remain the same, with a deviation of less than 5%. On the other hand, vibrations on the structure are reduced significantly. On average, vibration levels are reduced by 35% in different spots of the structure.

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

2000 ◽  
Vol 37 (6) ◽  
pp. 1283-1294 ◽  
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.

The bearing capacity of rigid piles and pile groups under inclined loads in layered sand

1981 ◽  
Vol 18 (4) ◽  
pp. 514-519 ◽  
Author(s):  
G. G. Meyerhof ◽  
S. K. Mathur ◽  
A. J. Valsangkar
Keyword(s):  
Bearing Capacity ◽  
Ultimate Bearing Capacity ◽  
Test Results ◽  
Pile Groups ◽  
Free Standing ◽  
Previous Theory ◽  
Inclined Loads ◽  
Load Tests ◽  
Batter Piles ◽  
Theory And Model

The ultimate bearing capacity of rigid vertical and batter piles and pile groups in layered sand has been determined under various inclinations of the load varying from the vertical to horizontal directions. The results of load tests on single model piles of different inclinations and on free-standing groups are compared with theoretical estimates. The influence of load inclination on the bearing capacity can be represented by simple interaction relationships between the axial and normal components of the ultimate load. The effect of eccentricity of the load on the ultimate bearing capacity of pile groups is discussed on the basis of previous theory and model test results.

Sign in / Sign up

Export Citation Format

Share Document