Application method of multi-ellipse and ring-shaped composite braces in deep and large mud foundation pit engineering

Abstract

The invention discloses an application method of a multi-elliptical annular composite brace in a deep and large mud foundation pit project, comprising: setting the number of layers of a multi-elliptical annular composite brace according to the depth of the foundation pit; performing outer cement mixing water stop piles and supports Pile construction; start the excavation of the first layer of earthwork in the foundation pit, and then build the first layer of multi-elliptical annular composite braces; when the first layer of multi-elliptical annular composite braces is completed and the strength reaches 85% of the design strength and above, start the second layer of earthwork Excavation; and by analogy, when each layer of multi-elliptical annular composite support is completed and the strength reaches 85% of the design strength and above, the excavation of the lower layer of earthwork will start until the bottom layer of the foundation pit is dug. The invention effectively shortens the waiting time for hardening of multi-elliptical annular composite braces, speeds up the progress of the project, and can ensure the safety and stability of the foundation pit. By observing the displacement of the foundation pit, the axial force of the support, and the surrounding settlement during the construction of the foundation pit, all the indicators within the safe value.

Description

technical field [0001] The invention relates to the technical field of foundation pit engineering construction, and more specifically, the invention relates to an application method of a multi-elliptical ring-shaped combined brace in deep and large mud foundation pit engineering. Background technique [0002] In recent years, with the gradual increase of underground projects, deep and large foundation pit projects under various complex geological conditions are also common. Especially in the process of underground construction in southern coastal cities, how to ensure deep and large foundation pits in advance before being safe, fast and economical? The construction of muddy foundation pit has become the top priority in engineering construction. [0003] As the main support system of deep and large foundation pits, the internal support has more and more forms, and the force is more and more reasonable. For different shapes of foundation pits, choosing a reasonable support for...

AI Technical Summary

Problems solved by technology

[0004] For special-shaped foundation pits with extremely poor geological conditions, the commonly used support method of corner braces + cross braces greatly increases the volume of the support system, and the long distance in the length and width directions directly leads to large cross-bracing sections.

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