(d) (1) (i) Observe soil samples being excavated and soil on the sides of the excavation. Estimate the range of particle sizes and the relative quantities of particle sizes. Soil, which consists mainly of fine-grained materials, is a cohesive material. Soil consisting mainly of sand or coarse-grained gravel is a granular material. (3) Excavations 20 feet deep or less that have vertical lateral underparts shall be shielded or supported at a height of at least 18 inches above the top of the vertical side. All these excavations must have a maximum permissible inclination of 1:1. (a) (1) Scope. This annex describes a method for classifying soil and rock deposits based on site and environmental conditions and the structure and composition of terrestrial deposits. The appendix provides definitions, establishes requirements, and describes acceptable visual and manual tests for use in soil classification. A visual test is a qualitative assessment of the conditions around the site.
In a visual test, the entire excavation site, including adjacent soil and excavated soil, is observed. If the soil remains in clumps, it is cohesive; If it appears to be sand or coarse-grained gravel, it is considered grainy. The evaluator also checks for signs of vibration. (1) The information is presented in tabular form in tables D-1.1, D-1.2, D-1.3 and E-1.4. Each table shows the maximum vertical and horizontal distances that can be used with different sizes of aluminum elements and different sizes of hydraulic cylinders. Each table contains data only for the specific type of soil in which the excavation or part of the excavation will be carried out. Tables D-1.1 and D-1.2 refer to vertical banks in type A and B soils. Tables D-1.3 and D1.4 refer to horizontal roller systems of types B and C. (b) (2) Option (2) – Determination of pitches and configurations on the basis of Appendices A and B. The maximum permissible inclinations and permissible configurations for inclined and bench systems shall be determined in accordance with the conditions and requirements set out in Appendices A and B to this Subsection. Recognized engineering practices are those requirements that meet the standards of practice required by a Chartered Professional Engineer.
Distress means that the ground is in a state where collapse is imminent or likely to occur. Distress is evidenced by phenomena such as the development of cracks before or next to an open excavation; sinking the edge of an excavation; the subsidence of face materials or the swelling or lifting of materials from the bottom of an excavation; chipping materials at the front of a construction pit; and ravelling, which is small amounts of materials such as pebbles or small pieces of material that suddenly separate from the surface of a construction pit and trickle or roll into the excavation. (e) (2) Additional requirements for trench support systems. (l) Gangways shall be provided when personnel or equipment are to or may pass through excavations. Gurardrails corresponding to 1926.502(b) must be present when the gangways are 6 feet (1.8 m) or more above the lower levels. (d) (1) Visual inspections. Visual analysis is performed to obtain qualitative information about the excavation site in general, the soil adjacent to the excavation, the soil that forms the sides of the open excavation, and the soil taken as samples of excavated material. 2 A maximum short-term inclination of 1/2H:1V (63 degrees) is permitted for excavations in Type A soils with a depth of 12 forages (3.67 m) or less. The maximum short-term slope allowed for excavations over 3.67 m (12 feet) is 3/4H:1V (53 degrees). (a) Scope. This appendix contains information that can be used for shoring wood is provided as a method of protection against collapse in trenches not exceeding 20 feet (6.1 m) deep.
This Appendix shall be used if the design of timber shoring protection systems is to be carried out in accordance with § 1926.652(c)(1). Other wood shoring configurations; other support systems such as hydraulic and pneumatic systems; and other protective systems such as inclined systems, inclined systems, shielding systems and freezing systems shall be designed in accordance with the requirements of paragraphs 1926.652(b) and 1926.652(c). Slope protection systems, benches or other approved collapse protection systems must be used in excavations 5 feet or deeper. For excavations more than 20 feet deep, the slope or bench must be designed by a licensed engineer. Input and output mean „input“ and „exit“ respectively. In excavation and excavation operations, they refer to the provision of safe means for employees to enter or exit a construction pit or trench. (c) the design of launchers, shield systems and other protective systems. The designs of beam, shielding and other protective systems shall be selected and constructed by the employer or his designate and shall conform to the requirements of subsection (c)(2) as follows: (i)(2)(iii) a registered professional engineer has approved the determination that the structure is sufficiently distant from the excavation pit not to be affected by excavation activities; or This figure illustrates the different types of slope excavation in stratified soils.
These include type A, B and C soils in single-slope excavations and various permutations such as: type A soil on types B and C individually, type B soil on types A and C individually, and type C soil on types A and B individually. Lower bell pillar hole refers to a type of well or foundation excavation whose bottom is larger than the cross-section above to form a bell shape. (b) soil classification. In order to use the data contained in this Annex, it is first necessary to determine the soil type(s) for which excavation will be carried out using the soil classification method described in Annex A to Subdivision P of this Part. (1) Vertical shoreline rails and horizontal cetaceans are those that meet the section module requirements of Tables D-1. The aluminum material is 6061-T6 or a material of equal strength and properties. (e) (1) (v) The distance begins at the bottom of the excavation and continues from there. The elements should be released slowly to notice signs of possible failure of the remaining elements of the structure or possible collapse of the sides of the excavation. Overburden should be placed to divert rainwater and other runoff away from the excavation. Overburden must be placed in such a way that it cannot accidentally hit the excavation, slip or fall back. (d) (2) (iii) penetration of the thumb. The thumb penetration test can be used to estimate the unlimited compressive strength of cohesive soils.
(This test is based on the thumb penetration test described in the American Society for Testing and Materials (ASTM) Standard Recommended Practice for Description of Soils (Visual – Manual Procedure).“) Type A floors with an unlimited compressive strength of 1.5 ctf can easily be sunk with the thumb; However, they can only be penetrated by the thumb with great effort. Type C floors with an unlimited compressive strength of 0.5 ctf can easily be penetrated several centimeters by the thumb and shaped by a slight pressure of the fingers.
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