CN-122016486-A - UHPC wet joint interface crack resistance evaluation method and system

CN122016486ACN 122016486 ACN122016486 ACN 122016486ACN-122016486-A

Abstract

The invention discloses an assessment method and an assessment system for UHPC wet joint interface crack resistance, which particularly relate to the technical field of material mechanical property testing, and are used for solving the problem that the conventional assessment method cannot reveal interface bonding failure and UHPC internal crack competition mechanism, acquiring real-time strain data through strain sensors arranged in an interface and an internal area, generating a corresponding strain evolution curve, extracting characteristic points of sudden increase of strain change rate from the strain evolution curve, intercepting the strain evolution sequence based on the characteristic points, calculating a dynamic time warping distance to quantify evolution asynchronism, judging competition relation dominant mode according to the characteristic points, finally outputting quantitative assessment indexes, realizing the transformation from a macroscopic image to a microscopic damage mechanism, and providing scientific basis for optimizing interface design and construction technology.

Inventors

YANG SHENG
WANG JING
LIU YONGSONG
YU HONG
SHI JIAHENG
SHAN HAITAO
Tian Peixia
LI LIANG
LIN HUANSONG
WANG JINGQUAN
XIE WEIWEI
HU YUQING
WANG JIDONG

Assignees

中交路桥建设有限公司
中交路桥华东工程有限公司
宿迁市公路事业发展中心

Dates

Publication Date: 20260512
Application Date: 20260416

Claims (10)

1. The UHPC wet joint interface crack resistance evaluation method is characterized by comprising the following steps of: S1, acquiring real-time strain data of an interface bonding area and an inner area of a UHPC body through a strain sensor arranged on a UHPC wet joint test piece; s2, respectively generating an interface bonding strain evolution curve and an UHPC internal strain evolution curve based on real-time strain data; s3, extracting a first characteristic point from the interface bonding strain evolution curve and extracting a second characteristic point from the UHPC internal strain evolution curve, wherein the first characteristic point and the second characteristic point correspond to the position of sudden increase of the strain change rate; s4, respectively extracting strain evolution feature sequences of an interface and an internal region based on the first feature points and the second feature points, quantifying evolution asynchronism of the two strain evolution feature sequences by calculating dynamic time warping distances of the two strain evolution feature sequences, and judging a competition relationship between interface bonding failure and UHPC internal cracking; s5, outputting quantitative evaluation indexes of the UHPC wet joint interface cracking resistance based on the competition relationship.
2. The method of evaluating crack resistance performance of a UHPC wet joint interface according to claim 1, wherein the acquiring of real-time strain data of the interface bonding region and the UHPC body interior region by strain sensors disposed on the UHPC wet joint test piece comprises: And arranging a first group of strain sensors in the interface bonding area in parallel with the interface direction, arranging a second group of strain sensors in the inner area of the UHPC body in a direction perpendicular to the potential cracking direction, and synchronously acquiring real-time strain data by the first group of strain sensors and the second group of strain sensors.
3. The method for evaluating the crack resistance of the wet joint interface of the UHPC according to claim 1, wherein the method for respectively generating the interface bonding strain evolution curve and the UHPC internal strain evolution curve based on the real-time strain data comprises the following steps: respectively carrying out time sequence alignment treatment on the real-time strain data, and eliminating high-frequency noise interference by adopting a moving average filtering method; Drawing real-time strain data of the interface bonding area after filtering into an interface bonding strain evolution curve; and simultaneously drawing real-time strain data of the inner area of the UHPC body after filtering into an UHPC inner strain evolution curve.
4. The method for evaluating crack resistance of a wet joint interface of a UHPC according to claim 1, wherein extracting a first feature point from an interfacial bonding strain evolution curve and extracting a second feature point from an internal strain evolution curve of the UHPC, the first feature point and the second feature point corresponding to positions where strain change rates suddenly increase, comprises: Respectively calculating first derivatives of the interface bonding strain evolution curve and the UHPC internal strain evolution curve to obtain a corresponding strain change rate curve; Identifying a first peak point and a second peak point which exceed a preset threshold in the strain change rate curve; and marking the position of the first peak point corresponding to the interface bonding strain evolution curve as a first characteristic point, and marking the position of the second peak point corresponding to the UHPC internal strain evolution curve as a second characteristic point.
5. The method for evaluating crack resistance of a wet joint interface of a UHPC according to claim 1, wherein the step of extracting the strain evolution feature sequences of the interface and the inner region based on the first feature point and the second feature point respectively, quantifying the evolution asynchronism by calculating the dynamic time warping distance of the two strain evolution feature sequences, and determining the competition relationship between the bonding failure of the interface and the internal crack of the UHPC comprises the steps of: Intercepting a set time window of an interface bonding strain evolution curve by taking a first characteristic point as a center as an interface strain evolution characteristic sequence; taking the second characteristic point as a center to intercept the same time window of the UHPC internal strain evolution curve as an internal strain evolution characteristic sequence; Quantifying the evolution asynchronism of the two strain evolution feature sequences by calculating the dynamic time warping distance of the two strain evolution feature sequences; And judging the competition relationship between the interface bonding failure and the UHPC internal cracking, wherein the competition relationship comprises a dominant competition relationship and a dominant synergistic relationship.
6. The method of claim 5, wherein quantifying evolution asynchronism comprises calculating a minimum regular path distance between an interface strain evolution feature sequence and an internal strain evolution feature sequence using a dynamic time warping algorithm.
7. The UHPC wet joint interface crack resistance assessment method of claim 5, wherein the relationship is determined to be dominant when the dynamic time warping distance is greater than a set threshold and the relationship is determined to be dominant when the dynamic time warping distance is less than or equal to the set threshold.
8. The UHPC wet joint interface crack resistance evaluation method according to claim 1, wherein outputting quantitative evaluation indexes of the UHPC wet joint interface crack resistance based on a competition relationship comprises: Mapping the numerical value of the dynamic time warping distance to a preset cracking performance grade division interval, and generating a corresponding cracking performance grade index according to the mapping result; the method comprises the steps of outputting a first grade index when the dynamic time warping distance is in a first numerical value interval, outputting a second grade index when the dynamic time warping distance is in a second numerical value interval, and outputting a third grade index when the dynamic time warping distance is in a third numerical value interval.
9. The method for evaluating the crack resistance of the UHPC wet joint interface according to claim 8, wherein mapping the value of the dynamic time warping distance to the preset crack resistance class division interval comprises establishing a corresponding relation between the value of the dynamic time warping distance and the crack resistance class, wherein a smaller dynamic time warping distance corresponds to a higher crack resistance class and a larger dynamic time warping distance corresponds to a lower crack resistance class, and converting the calculated value of the dynamic time warping distance into a corresponding crack resistance class index by inquiring the established corresponding relation.
10. A UHPC wet joint interface crack resistance evaluation system for implementing a UHPC wet joint interface crack resistance evaluation method according to any one of claims 1-9, comprising the following modules: the strain acquisition module is used for acquiring real-time strain data of the interface bonding area and the inner area of the UHPC body through a strain sensor arranged on the UHPC wet joint test piece; The curve generation module is used for respectively generating an interface bonding strain evolution curve and an UHPC internal strain evolution curve based on the real-time strain data; the characteristic extraction module is used for extracting a first characteristic point from the interface bonding strain evolution curve and extracting a second characteristic point from the UHPC internal strain evolution curve, wherein the first characteristic point and the second characteristic point correspond to the position of sudden increase of the strain change rate; The competition judging module is used for respectively extracting strain evolution characteristic sequences of the interface and the internal area based on the first characteristic points and the second characteristic points, quantifying the evolution asynchronism of the two strain evolution characteristic sequences by calculating the dynamic time regular distance of the two strain evolution characteristic sequences, and judging the competition relationship between the bonding failure of the interface and the internal cracking of the UHPC; the index evaluation module is used for outputting quantitative evaluation indexes of the UHPC wet joint interface cracking resistance based on the competition relation.

Description

UHPC wet joint interface crack resistance evaluation method and system Technical Field The invention relates to the technical field of mechanical property testing of materials, in particular to a UHPC wet joint interface crack resistance evaluation method and a UHPC wet joint interface crack resistance evaluation system. Background In the field of bridge engineering, ultra-high performance concrete is widely used for wet joint connection of composite beam structures due to its excellent mechanical properties and durability. The interfacial crack resistance of the part directly determines the structural integrity and long-term service life. Currently, for those skilled in the art, a conventional method for evaluating the crack resistance of a wet seam interface of UHPC mainly relies on performing a direct mechanical property test, such as an axial tensile or bending test, on a molded test piece, and evaluating the performance of the test piece by measuring its ultimate bearing capacity or observing its macroscopic damage morphology. However, such assessment methods are essentially focused on a final mechanical state result, and it is difficult to reveal a potential, competitive mechanism of damage evolution within the wet joint under load and constraints. Specifically, under the actual complex multidimensional constraint condition, the failure of the interface area may be caused by two distinct but competing mechanisms, namely debonding caused by interface bonding failure and cracking caused by stress concentration in the UHPC body, so that the prior art cannot effectively distinguish and quantify the dominant effect of the two failure modes in the failure process and the evolution rule thereof, and the evaluation conclusion stays in a macroscopic appearance, and cannot provide criteria reflecting the inherent mechanism for the targeted optimization of the interface treatment process or material design. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a UHPC wet joint interface crack resistance evaluation method and a UHPC wet joint interface crack resistance evaluation system, which are used for solving the problems in the prior art. In order to achieve the above purpose, the present invention provides the following technical solutions: A UHPC wet joint interface crack resistance evaluation method comprises the following steps: S1, acquiring real-time strain data of an interface bonding area and an inner area of a UHPC body through a strain sensor arranged on a UHPC wet joint test piece; s2, respectively generating an interface bonding strain evolution curve and an UHPC internal strain evolution curve based on real-time strain data; s3, extracting a first characteristic point from the interface bonding strain evolution curve and extracting a second characteristic point from the UHPC internal strain evolution curve, wherein the first characteristic point and the second characteristic point correspond to the position of sudden increase of the strain change rate; s4, respectively extracting strain evolution feature sequences of an interface and an internal region based on the first feature points and the second feature points, quantifying evolution asynchronism of the two strain evolution feature sequences by calculating dynamic time warping distances of the two strain evolution feature sequences, and judging a competition relationship between interface bonding failure and UHPC internal cracking; s5, outputting quantitative evaluation indexes of the UHPC wet joint interface cracking resistance based on the competition relationship. Further, acquiring real-time strain data of the interface bonding region and the UHPC body interior region by a strain sensor disposed on the UHPC wet joint test piece, comprising: And arranging a first group of strain sensors in the interface bonding area in parallel with the interface direction, arranging a second group of strain sensors in the inner area of the UHPC body in a direction perpendicular to the potential cracking direction, and synchronously acquiring real-time strain data by the first group of strain sensors and the second group of strain sensors. Further, generating an interface bonding strain evolution curve and a UHPC internal strain evolution curve based on the real-time strain data respectively, including: respectively carrying out time sequence alignment treatment on the real-time strain data, and eliminating high-frequency noise interference by adopting a moving average filtering method; Drawing real-time strain data of the interface bonding area after filtering into an interface bonding strain evolution curve; and simultaneously drawing real-time strain data of the inner area of the UHPC body after filtering into an UHPC inner strain evolution curve. Further, extracting a first feature point from the interfacial bonding strain evolution curve and extracting a second feature point from the UHPC internal strain e