{"id":387003,"date":"2024-10-20T03:38:05","date_gmt":"2024-10-20T03:38:05","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/astm-d4506-2021\/"},"modified":"2024-10-26T06:38:51","modified_gmt":"2024-10-26T06:38:51","slug":"astm-d4506-2021","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/astm\/astm-d4506-2021\/","title":{"rendered":"ASTM-D4506 2021"},"content":{"rendered":"
Scope<\/strong><\/p>\n 1.1<\/span> This test method is used to determine the in situ modulus of deformation of rock mass by subjecting a test chamber in rock of a circular cross-section to uniformly distributed radial loading; the consequent rock radial displacements are measured at various locations, from which the deformation modulus may be calculated. The radial anisotropic deformability of the rock is taken at enough locations that it can also be determined from the differences between the extensometer readings taken at various locations along and around the test chamber as well with depth from each loading sequence. Information on time-dependent deformation may be obtained as well by holding the loads constant for selected time intervals.<\/p>\n Note 1:<\/span> Deformations caused by a cylindrical test chamber are not likely uniform even if each steel ring forming the jack is uniformly loaded. Theoretically, the deformations will vary along the cylinder such that it looks like a gaussian probability curve.<\/span><\/p>\n<\/p><\/div>\n<\/p><\/div>\n 1.2<\/span> This test method is based upon the procedures developed by the US Bureau of Reclamation, featuring long extensometers that provide a bottom anchor far enough away from the test zone to be used as a zero reference point (Fig. 1<\/span>)(1<\/span>)<\/span>.2<\/span><\/span> An alternative procedure, the New Austrian method, is also available and is based on a reference bar going down the middle to support posts outside the deflection zone due to the testing loads and shown in Fig. 2<\/span> (2<\/span>)<\/span>. Other than a different method of taking deformation readings, the two field tests are the same. Additional information on radial jacking and data analysis is presented in References (3-<\/span>8<\/span>)<\/span>.<\/p>\n FIG. 1<\/span> General Diagram and Scheme of a Radial Jacking Test Setup used by the US Bureau of Reclamation (1<\/span>, 9<\/span><\/span>)<\/b><\/p>\n<\/p><\/div>\n<\/p><\/div>\n FIG. 2<\/span> Longitudinal, Cross-section, and Close-up View of the Radial Jacking Test Setup (2<\/span><\/span>)<\/b><\/p>\n<\/p><\/div>\n