The excavated tunnel zone, without a defined interface, that contains soil and coarse fractions of gravels, cobbles, and boulders (i.e., silt with boulders). This term is not currently defined by ASTMAmerican Society of Testing and Materials; technical organization formed for the development of standards on characteristics and performance of materials, products, systems and services, and the promotion of related knowledge. or USCS.
Refers to a significant change in ground type, characteristics, or behavior along the excavated tunnel between the jacking and receiving shafts. This term is not currently defined by ASTM or USCS.
(1) A written amendment of the contract documents signed by both parties. (2) A change order. (c) A written clarification or interpretation issued by the engineer in accordance with the terms of the contract. (d) A written order for a minor change or alteration in the work issued by the engineer pursuant to the terms of the contract. A modification may only be issued after execution of the agreement.
A range of techniques in which the liner is reduced in cross sectional diameter before insertion into the Carrier PipePipe for conveyance of water, gas, sewage, or other products and services. Some carrier pipe can be installed by direct jacking (i.e. one-pass microtunneling).. It is subsequently restored to close to its original diameter, generally forming a close fit with the original pipe. Methods of cross sectional area reduction include squeezing, folding into a U-shape or stretching. See LiningA rehabilitation process where a length of material is introduced to extend the life of the existing sewer. The lining may or may not utilize some structural strength from the existing sewer, and it may or may not function as a structural enhancement within the existing sewer, or an internal non-structural coating or lining material applied to a pipe. with Close-fitDescription of a lining system in which the new pipe makes close contact with the defective pipe at normal or minimum diameter. An annulus may occur in sections where the diameter of the defective pipe is in excess of this. Pipes.
The stress required to produce strain, which may be a change of length (Young’s modulus); a twist or shear (modulus); a twist or sheat (modulus or rigidity); or a change of volume (bulk modulus), expressed in dynes per square centimeter.