CN-121976523-A - Roadbed slide-resistant pile hierarchical jump trench excavation and support construction method

CN121976523ACN 121976523 ACN121976523 ACN 121976523ACN-121976523-A

Abstract

The application belongs to the technical field of roadbed construction, and particularly relates to a method for excavating and supporting a roadbed slide-resistant pile in a hierarchical jump way. According to the method, based on the distribution characteristics of the pile groups of the anti-slide piles and the geological data of the pile position areas, a jump-groove excavation sequence and a stepped excavation amplitude adjustment rule are determined, stepped excavation of pile holes is sequentially carried out, the stepped amplitude is adjusted in an adaptive mode, supporting structures adaptive to excavation depth and stratum types are synchronously constructed step by step, and all anti-slide pile construction is completed in a circulating mode. According to the application, through optimizing the excavation time sequence and arranging the stepped amplitude and the supporting structure in a grading manner, different stratum working conditions are adapted, the soil disturbance is effectively reduced, the stratum instability risk is reduced, the adaptability and the construction stability of the supporting structure are improved, and the construction quality and the safety of the construction process of the slide-resistant pile are improved.

Inventors

LI JINYOU
WANG HAIHUA
YANG JIANHUA
DENG HAO
QI SHICHAO
MIAO YI
SONG XINYU
FAN FUQIANG
LIU HAO
LONG BING

Assignees

中铁贵州工程有限公司
中国铁建昆仑投资集团有限公司
贵州黔中高速公路开发有限公司

Dates

Publication Date: 20260505
Application Date: 20260408

Claims (10)

1. The construction method for the stepped jump trench excavation and support of the roadbed slide-resistant pile is characterized by comprising the following steps of: S1, determining an adjustment rule of a jump trench excavation sequence and a stepped excavation amplitude based on pile group distribution characteristics of the anti-slide piles and pile position area geological distribution data, wherein the adjustment rule corresponds to stratum types; s2, performing pile hole hierarchical excavation according to the jump trench excavation sequence, and adjusting the hierarchical excavation amplitude according to the adjustment rule according to the stratum type revealed in real time; s3, synchronously constructing a supporting structure matched with the current accumulated excavation depth and the stratum type revealed in real time when the first-order pile hole excavation is completed; s4, repeating S2 to S3 after completing all the step excavation and corresponding supporting construction of the single pile hole, and completing all the construction of the anti-slide pile.
2. The method of claim 1, wherein the jump trench excavation sequence is determined based on the pile group distribution characteristics, single row piles are excavated at intervals, and group piles are excavated diagonally alternately; And the construction time sequence interval of the adjacent anti-slide pile bodies is larger than an interval threshold value.
3. The method of claim 1, wherein the anti-skid piles comprise a probe pile and a main force pile, and the jump trench excavation sequence is: Finishing the hierarchical excavation and supporting construction of the exploratory pile; correcting the adjustment rule of the hierarchical excavation amplitude through the stratum type revealed in real time in the heuristic pile excavation process; and carrying out the hierarchical excavation and supporting construction of the main force pile based on the corrected adjustment rule.
4. The method of claim 1, wherein the adjustment rule for the stepped excavation magnitude is: The stratum type is stabilized correspondingly, and the stepped excavation amplitude adopts a first stepped amplitude; The stratum type corresponding to loosening, crushing or water enrichment is adopted, and the step excavation amplitude adopts a second step amplitude; The second stepped amplitude is smaller than the first stepped amplitude.
5. The method of claim 1, wherein the rules for constructing the support structure adapted to the currently accumulated excavation depth, the formation type revealed in real time, are: The supporting structure adopts a basic retaining wall structure corresponding to the stable stratum type; When the stratum type corresponding to loosening, crushing or water enrichment or the current accumulated excavation depth exceeds a depth threshold value, the supporting structure adopts a reinforced wall protection structure additionally provided with a reinforced rib net; and the supporting structure adopts a composite supporting structure combining a retaining wall and an isolation protective layer corresponding to the extremely unstable stratum type.
6. The method according to claim 1, wherein in the pile hole step excavation process, when exposing the water-rich stratum type, adopting a corresponding precipitation mode according to the stratum water-rich range, specifically comprising: When the water-rich range of the stratum is lower than the water-rich threshold, adopting an in-hole water collection and discharge mode; And when the water-rich range of the stratum reaches or exceeds the water-rich threshold, adopting a multi-pile hole dewatering mode to reduce the underground water level below the current excavation surface.
7. The method according to claim 4, wherein in the pile hole step excavation process, when the stratum type of the quicksand or silt is revealed, a corresponding excavation and support mode is adopted, which specifically comprises: wrapping the hole wall of the corresponding pile hole by adopting an isolation protection structure; the stepped excavation amplitude adopts a third stepped amplitude, the third stepped amplitude is smaller than the second stepped amplitude; And synchronizing Shi Zuodui the support structures with the required orders after the first-order pile holes are excavated.
8. The method of claim 5, wherein in the pile hole staged excavation process, when the formation type of karst cave or broken rock is revealed, a corresponding treatment and support mode is adopted, which specifically comprises: the composite supporting structure is applied after the filling material is adopted to be densely filled corresponding to the karst cave without the filler; and (3) removing loose fillers in the karst cave or broken rock stratum corresponding to the fillers, then reinforcing and filling, and then applying the reinforced retaining wall structure or the composite supporting structure according to the stability of the stratum.
9. The method according to claim 5, wherein during the pile hole staged excavation and support construction, the method further comprises adjusting ventilation mode according to the current accumulated excavation depth, and specifically comprises: When the current accumulated excavation depth is lower than the depth threshold value, adopting a natural ventilation mode; And when the current accumulated excavation depth reaches or exceeds the depth threshold value, continuously replacing air in the pile hole by adopting a forced ventilation mode.
10. The method according to claim 9, wherein during the pile hole staged excavation and support construction process, the method further comprises synchronously performing gas monitoring, specifically comprising: And (3) monitoring the concentration of toxic and harmful gases in the pile hole in real time, and triggering early warning and strengthening ventilation intensity when the concentration of the gases exceeds a concentration threshold value.

Description

Roadbed slide-resistant pile hierarchical jump trench excavation and support construction method Technical Field The application relates to the technical field of roadbed construction, in particular to a method for excavating and supporting a roadbed slide-resistant pile step-by-step jump. Background The roadbed anti-slide pile belongs to the category of geotechnical engineering foundation support, is a common construction technology for roadbed slope anti-slide reinforcement and ensuring roadbed foundation stability, and is widely applied to various roadbed foundation engineering. The traditional anti-slide pile excavation supporting construction mostly adopts a conventional continuous excavation mode, the excavation operation is easy to generate concentrated disturbance on soil around the pile, the excavation and the supporting construction are difficult to realize synchronous connection, the problems of wall soil instability, slippage and the like are easily caused, the continuity of the foundation construction of the anti-slide pile is affected, the integral anti-slide protection effect of the anti-slide pile is weakened, and the requirements on the stability and the reliability of the foundation construction of a roadbed under complex working conditions cannot be met. Disclosure of Invention In order to solve or at least partially solve the technical problems, the application provides a method for excavating and supporting a foundation slide-resistant pile step-by-step jump. The application provides a method for excavating and supporting a roadbed slide-resistant pile step-by-step jump, which comprises the following steps: S1, determining an adjustment rule of a jump trench excavation sequence and a stepped excavation amplitude based on pile group distribution characteristics of the anti-slide piles and pile position area geological distribution data, wherein the adjustment rule corresponds to stratum types; s2, performing pile hole hierarchical excavation according to the jump trench excavation sequence, and adjusting the hierarchical excavation amplitude according to the adjustment rule according to the stratum type revealed in real time; s3, synchronously constructing a supporting structure matched with the current accumulated excavation depth and the stratum type revealed in real time when the first-order pile hole excavation is completed; s4, repeating S2 to S3 after completing all the step excavation and corresponding supporting construction of the single pile hole, and completing all the construction of the anti-slide pile. Optionally, determining the jump trench excavation sequence based on the pile group distribution characteristics, wherein the single-row piles adopt an interval excavation mode, and the group piles adopt a diagonal alternate excavation mode; And the construction time sequence interval of the adjacent anti-slide pile bodies is larger than an interval threshold value. Optionally, the anti-slide pile comprises a probing pile and a main force pile, and the jump trench excavation sequence is as follows: Finishing the hierarchical excavation and supporting construction of the exploratory pile; correcting the adjustment rule of the hierarchical excavation amplitude through the stratum type revealed in real time in the heuristic pile excavation process; and carrying out the hierarchical excavation and supporting construction of the main force pile based on the corrected adjustment rule. Optionally, the adjustment rule of the stepped excavation amplitude is: The stratum type is stabilized correspondingly, and the stepped excavation amplitude adopts a first stepped amplitude; The stratum type corresponding to loosening, crushing or water enrichment is adopted, and the step excavation amplitude adopts a second step amplitude; The second stepped amplitude is smaller than the first stepped amplitude. Optionally, the construction rules of the support structure adapted to the stratum type disclosed in real time and the current accumulated excavation depth are as follows: The supporting structure adopts a basic retaining wall structure corresponding to the stable stratum type; When the stratum type corresponding to loosening, crushing or water enrichment or the current accumulated excavation depth exceeds a depth threshold value, the supporting structure adopts a reinforced wall protection structure additionally provided with a reinforced rib net; and the supporting structure adopts a composite supporting structure combining a retaining wall and an isolation protective layer corresponding to the extremely unstable stratum type. Optionally, in the pile hole step excavation process, when the stratum type rich in water is uncovered, adopting a corresponding precipitation mode according to the stratum water-rich range, and specifically including: When the water-rich range of the stratum is lower than the water-rich threshold, adopting an in-hole water collection and discharge mode; And when the