Author: KR. Reddy Publisher: ISBN: Category : Cementation Languages : en Pages : 17
Book Description
A stress-controlled, flexible boundary, true (or cubical) triaxial apparatus has been developed to investigate the behavior of cemented sand under various stress paths which are not achievable using conventional axisymmetric triaxial apparatus. The apparatus components, specimen preparation, and test procedure are described. Tests were performed on cemented sand along different stress paths which included hydrostatic compression, conventional triaxial compression, and along different directions on octahedral planes. The test results indicate that stress-strain and volumetric response of cemented sand depends on stress path.
Author: LR. Hoyos Publisher: ISBN: Category : Axis-translation technique Languages : en Pages : 9
Book Description
A servo-controlled, true triaxial (cubical) testing apparatus has been modified to test 10-cm cubical specimens of unsaturated soil under suction-controlled conditions and for a wide range of stress paths. The equipment is a mixed-boundary type of device, with the specimen seated on top of a saturated high-air-entry disk and between five flexible membranes on the remaining sides of the cube. This paper describes the development of the device, including details of main apparatus components, specimen preparation, step-by-step assembling procedure, and the corresponding validation of its suitability for testing unsaturated soils. The device features two independent pore-air pressure and pore-water pressure control/monitoring systems. Matric suction states in the specimens are induced and maintained constant during testing by using the axis-translation technique. A companion paper (Macari and Hoyos Jr. 2001) presents the results from a comprehensive experimental study of the stress-strain response of a recompacted silty sand following simple-to-complex stress paths under suction-controlled conditions.
Author: Marek Kwasniewski Publisher: CRC Press ISBN: 0415687233 Category : Technology & Engineering Languages : en Pages : 386
Book Description
This is the first book ever published on the problems of true triaxial testing of rocks addressing all aspects of true triaxial testing of rocks, including: (i) true triaxial testing techniques and procedures; (ii) test results: strength, deformability, failure mode, permeability, acoustic emission, and elastic wave velocity; (iii) constitutive laws and failure criteria; and (iv) applications to geoengineering and geosciences. Recent developments in the field of true triaxial testing of rocks are presented, as well as a thorough review of the most important achievements in the whole history of true triaxial testing of rocks. Almost all researchers from around the world engaged in the true triaxial testing of rocks over the last three decades have contributed to this work. The authors originate from different branches of geoengineering and geosciences, including civil engineering, engineering geology, geotechnical engineering, mining engineering, petroleum engineering, seismology, and tectonophysics.
Author: Marek Kwasniewski Publisher: CRC Press ISBN: 0203138104 Category : Technology & Engineering Languages : en Pages : 384
Book Description
This is the first book ever published on the problems of true triaxial testing of rocks addressing all aspects of true triaxial testing of rocks, including: (i) true triaxial testing techniques and procedures; (ii) test results: strength, deformability, failure mode, permeability, acoustic emission, and elastic wave velocity; (iii) constitutiv
Author: Changho Choi Publisher: ISBN: Category : Coarse-grained soil Languages : en Pages : 13
Book Description
This paper presents a recently developed true triaxial apparatus and a series of verification studies. The apparatus is capable of handling 241-mm cubical specimens providing the means for testing specimens under a wide variety of stress paths under drained and undrained conditions. It uses flexible boundaries to apply three independently controlled principal stresses with back pressure. The apparatus also uses a fully computer-controlled electro-pneumatic loading system with advanced technology for data control. A testing program is presented for the purpose of verification. Pea-gravel specimens with D50=6.6 mm were tested under fully stress-controlled loading conditions. Stress paths used in this verification study include undrained and drained constant total mean stress paths and conventional triaxial compression and extension stress paths. Results from this study indicate that the newly developed apparatus is capable of capturing the stress-strain characteristics of coarse-grained soils.
Author: JS. Welsh Publisher: ISBN: Category : Axial loads Languages : en Pages : 15
Book Description
An electromechanical testing facility capable of applying any combination of tensile and/or compressive forces to three mutually orthogonal axes of a thickness-tapered composite cruciform specimen was designed, fabricated, assembled, and evaluated. Any stress ratio in biaxial (?1 - ?2) or triaxial (?1 - ?2 - ?3) stress space can be explored using this computer-controlled test facility. A brief description of the testing machine and its capabilities as well as the present test specimen design is included. Once fully assembled, uniaxial and biaxial tests were performed on 6061-T6 aluminum using this facility. The excellent agreement between the uniaxial and biaxial results obtained in the present study for this material, with accepted handbook values and applicable failure theories, confirmed the performance of several aspects of the testing facility. These aspects included the intra-axis alignment, machine compliance, specimen fabrication and testing procedures, automated computer testing algorithms, data acquisition algorithms, and calibration values. In addition, biaxial and triaxial tests were performed on an AS4/3501-6 carbon/epoxy cross-ply laminate. While most of these tests are considered valid, they revealed aspects of the present thickness-tapered cruciform specimen design that could be improved. More specifically, an undesirable failure mode was encountered in some biaxial tension tests, and triaxial tension tests were not performed successfully. Nevertheless, the overall acceptable performance of the triaxial testing facility is believed to have been demonstrated.
Author: Jae Hyun Park Publisher: ISBN: 9780542226946 Category : Civil engineering Languages : en Pages :
Book Description
A stress-controlled, flexible boundary, true triaxial (cubical) testing apparatus has been developed to test 3-inch cubical specimen of partially saturated soil under different moisture contents and for a wide range of multiaxial stress paths. A series of HC, CTC, TC, TE, and SS tests were conducted in order to perform a thorough performance and check-out verification testing of the newly developed device by investigating the multiaxial stress-strain response of partially saturated silty sand specimens artificially prepared in the laboratory. The development of the apparatus, specimen preparation process, test procedure, and the corresponding validation of its suitability for testing partially saturated sandy soils are described. In this work, specimens were prepared using a dual-mesh pluviation technique at four different moisture contents: w = 2.0, 4.5, 5.3, and 6.1%. In all cases, initial total soil suction was induced and found to exert a paramount influence on the stress-strain-strength behavior of partially saturated silty sand.
Author: KR. Reddy
Author: Heath S. Williams
Author: Kirsten Hendrik Albertus Daniel
Author: LR. Hoyos
Author: Marek Kwasniewski
Author: Marek Kwasniewski
Author: Kirsten Hendrik Albertus Daniel
Author: Changho Choi
Author: JS. Welsh
Author: Jae Hyun Park