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.

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 Experimental Study on Improvement of Marine Soft Soil with Alkali Residue

2018 ◽  
Vol 53 ◽  
pp. 04021
Author(s):  
SHAO Yong ◽  
LIU Xiao-li ◽  
ZHU Jin-jun
Keyword(s):  
Experimental Study ◽  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Void Ratio ◽  
Soft Soil ◽  
Compressive Modulus ◽  
Engineering Properties ◽  
Test Results ◽  
Use Of Resources ◽  
One Year

Industrial alkali slag is the discharge waste in the process of alkali production. About one million tons of alkali slag is discharged in China in one year. It is a burden on the environment, whether it is directly stacked or discharged into the sea. If we can realize the use of resources, it is a multi-pronged move, so alkali slag is used to improve solidified marine soft soil in this paper. The test results show that the alkali residue can effectively improve the engineering properties of marine soft soil. Among them, the unconfined compressive strength and compressive modulus are increased by about 10 times, and the void ratio and plasticity index can all reach the level of general clay. It shows that alkali slag has the potential to improve marine soft soil and can be popularized in engineering.

An Experiment for Effects of Different Additives on Strength of Sediment Solidification

2013 ◽  
Vol 357-360 ◽  
pp. 1235-1240 ◽  
Author(s):  
Guan Huan Chen ◽  
Jian Zhong Zhu
Keyword(s):  
Compressive Strength ◽  
Electron Microscope ◽  
Unconfined Compressive Strength ◽  
Scan Electron Microscope ◽  
Dredged Sediment ◽  
Comparative Tests ◽  
Cement Based Materials

The solidification method is a significant and resultful method for the disposal of dredged sediment. Solidified agents can be employed to improve the unconfined compressive strength (UCS) of sediment solidification. In this work, considering of economy and practicability, three kinds of optimized compound additives are selected and investigated on the effects of UCS of sediment solidification. 7d., 14d.and 28d. solidification stadium were taken to test the UCS of samples. Results showed that the activator had the best effect on increasing the UCS. The comparative tests also indicated that adding any kind of additive into the cement-based materials could improve the UCS of sediment solidification, the highest value of UCS was 11.02MPa (SCAHR). By means of scan electron microscope (SEM) technology, the microstructure images of the raw sample and solidified sample were obtained, which help to understand the development of UCS of the solidified sediments.

Research on mechanical behavior of L-shaped multi-cell concrete-filled steel tubular stub columns under axial compression

2018 ◽  
Vol 22 (2) ◽  
pp. 427-443 ◽  
Author(s):  
Jiepeng Liu ◽  
Hua Song ◽  
Yuanlong Yang
Keyword(s):  
Finite Element ◽  
Compressive Strength ◽  
Bearing Capacity ◽  
Thickness Ratio ◽  
Steel Plates ◽  
Test Results ◽  
Finite Element Program ◽  
Element Program ◽  
Compressive Strength Of Concrete ◽  
Stub Columns

A total of 11 L-shaped multi-cell concrete-filled steel tubular stub columns were fabricated and researched in axial compression test. The key factors of width-to-thickness ratio D/ t of steel plates in column limb and prism compressive strength of concrete fck were investigated to obtain influence on failure mode, bearing capacity, and ductility of the specimens. The test results show that the constraint effect for concrete provided by multi-cell steel tube cannot be ignored. The ductility decreases with the increase of width-to-thickness ratio D/ t of steel plates in column limb. The bearing capacity increases and the ductility decreases with the increase in prism compressive strength of concrete fck. A finite element program to calculate concentric load–displacement curves of L-shaped multi-cell concrete-filled steel tubular stub columns was proposed and verified by the test results. A parametric analysis with the finite element program was carried out to study the influence of the steel ratio α, steel yield strength fy, prism compressive strength of concrete fck, and width-to-thickness ratio D/ t of steel plates in column limb on the stiffness, bearing capacity and ductility. Furthermore, the design method of bearing capacity was determined based on mainstream concrete-filled steel tubular codes.

Correlation between Unconfined Compressive Strength and Penetration Index Obtained from DCP Tests for Cemented Lateritic Soils

2019 ◽  
Vol 814 ◽  
pp. 399-403
Author(s):  
Anuchit Uchaipichat
Keyword(s):  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Cement Content ◽  
Lateritic Soil ◽  
Test Results ◽  
Cone Penetration ◽  
Penetration Index ◽  
Curing Period ◽  
Cemented Soils ◽  
The Relationship

This paper presents the relationship between the dynamic cone penetration (DCP) test results and the unconfined compressive strength of lateritic cemented soils. A series of DCP tests and unconfined compressive strength was performed on lateritic cemented soil. The soils sample used in this study was lateritic soil. The test results for the DCP tests are presented in terms of penetration index. It can be observed that the penetration index decreased with increasing curing period and cement content. Moreover, the unconfined compressive strength of cemented soils increased with curing period and cement content. The relationship between unconfined compressive strength and penetration index is presented. A unique relationship for unconfined compressive strength can be obtained.

Assesment of Main Models for Predicting Debonding Load-Bearing Capacity against Intermediate Crack-Induced Debonding Failure in FRP-Strengthened RC Beams

2011 ◽  
Vol 311-313 ◽  
pp. 1941-1944
Author(s):  
Gui Bing Li ◽  
Yu Gang Guo ◽  
Xiao Yan Sun
Keyword(s):  
Bearing Capacity ◽  
Failure Mode ◽  
Failure Modes ◽  
Rc Beams ◽  
Test Results ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Accuracy Test ◽  
New Models ◽  
Debonding Load

intermediate crack-induced debondingis one of the most dominant failure modes in FRP-strengthened RC beams. Different code models and provisions have been proposed to mitigateintermediate crack-induced debondingfailure.However, these models and provisions can not mitigate this failure mode effectively. Recnetly, new models have been proposed to solve this problem. Out of all the existing models, four typical ones are investigated in the current study. A comprehensivecomparison among these models is carried out in order to evaluate their performance and accuracy. Test results offlexural specimens with intermediate crack-induced debonding failurecollected from the existing literature are used in the current comparison. The effectivenessand accuracy of each model have been evaluated based on these experimental results. It is shown that the current modals are all conservative and inadequite to effectively mitigate intermediate crack-induced debonding in flexurally strengthened members.

Experimental Investigations on the Seismic Behavior of Precast Concrete Columns with Novel Box Connections

2019 ◽  
Vol 14 (02) ◽  
pp. 2050007
Author(s):  
Xizhi Zhang ◽  
Shengbo Xu ◽  
Shaohua Zhang ◽  
Gaodong Xu
Keyword(s):  
Energy Dissipation ◽  
Bearing Capacity ◽  
Failure Mode ◽  
Seismic Behavior ◽  
Load Transfer ◽  
Precast Concrete ◽  
Hysteretic Behavior ◽  
Experimental Investigations ◽  
Test Results ◽  
Energy Dissipation Capacity

In this study, two types of novel box connections were developed to connect precast concrete (PC) columns and to ensure load transfer integrity. Cyclic loading tests were conducted to investigate the seismic behavior of the PC columns with proposed connections as well as the feasibility and reliability of novel box connections. The failure mode, hysteretic behavior, bearing capacity, ductility, stiffness degradation and energy dissipation were obtained and discussed. The test results indicated that the all PC columns exhibited the ductile flexural failure mode and that the proposed connections could transfer the force effectively. The adoption of novel box connections could improve the deformation capacity and energy dissipation capacity of PC columns. A higher axial compression ratio could enhance the bearing capacity of PC column with proposed connection but would significantly deteriorate the ductility and energy dissipation capacity. Finite element models were developed and the feasibility of the models was verified by the comparison with the test results.

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.

Predicting the overall horizontal bearing capacity of jack-up rigs using deck–foundation–soil-coupled model

2020 ◽  
pp. 147509022092590
Author(s):  
Qilin Yin ◽  
Jinjin Zhai ◽  
Sheng Dong
Keyword(s):  
Bearing Capacity ◽  
Failure Mode ◽  
Double Layer ◽  
Soft Clay ◽  
Coupled Model ◽  
Single Layer ◽  
Horizontal Load ◽  
Foundation Soil ◽  
Failure Envelopes ◽  
Jack Up

The overall bearing capacity of a jack-up rig under horizontal load is conducted using finite element models that consider the deck–foundation–soil interaction. In these models, the simplified horizontal load acts on the deck and increases until the platform loses its stability. The effects of the self-weight of the platform W and load direction α on the ultimate horizontal bearing capacity Hult are investigated, and W- Hult failure envelopes under different α conditions are obtained. Two typical seabed types, including the double-layer seabed of sand overlying soft clay and the single-layer seabed of sand, are considered. The results show that a critical self-weight Wcritical exists in the double-layer seabed. Based on Wcritical, the failure of the platform presents two different modes. When W <  Wcritical, the windward leg is pulled up, and Hult increases with the increase in W. When W >  Wcritical, the failure mode is the leeward leg or legs puncturing the bearing sand layer, and Hult decreases with the increase in W. In the single-layer seabed, the failure mode is the windward leg being pulled up, and Hult increases with the increase in W throughout the whole range. The W- Hult envelopes in these two types of seabeds are basically the same when W <  Wcritical.

scholarly journals The Time Effect and Micromechanism of the Unconfined Compressive Strength of Cement Modified Slurries

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Ping Jiang ◽  
Yewen Chen ◽  
Lin Zhou ◽  
Tianhao Mao ◽  
Wei Wang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Cement Content ◽  
Raw Materials ◽  
Time Effect ◽  
Test Results ◽  
X Ray ◽  
Strength Change ◽  
Effect Model ◽  
Curing Age

This study investigated the unconfined compressive strength change law of cement modified slurries (CMS) under different curing ages. We conducted unconfined compressive strength tests using slurry and cement as raw materials. The cement contents were 5%, 10%, 15%, 20%, and 25%. The curing ages were 7, 14, 28, 56, 90, 120, 150, and 180 d. A time effect model of CMS strength was established based on the measured UCS strength-curing age and the strength-cement content curves. The test results proved that the UCS of the CMS increased significantly with an increase in the curing age, and after 90 days, the UCS gradually increased to a fixed value. The time effect model better characterized the relationship between the UCS of the CMS and the curing age and the cement content, as the predicted value had a high correlation with the measured value. We conducted scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) tests to analyze the microstructure and chemical composition of the CMS. The microscopic test results demonstrated that the increase of cement content and curing age increased the amount of gelling substances in the CMS and made the overall structure more compact, thereby increasing its macro strength.

Sign in / Sign up

Export Citation Format

Share Document