Slope retaining structure horizontal load test method and system

Abstract

The invention provides a slope retaining structure horizontal load test method and system, and belongs to the field of geotechnical engineering in-situ test. The method comprises the following steps: sinking a retaining structure to a test elevation by utilizing a controlled sinking construction method, dynamically designing a window period before permanent foundation construction, arranging a detachable temporary vertical support member to ensure the stability of the retaining structure, switching to a test mode, providing rock-soil counterforce through the retaining structure, and carrying out test on the retaining structure. And the controllable loading supporting rod is used for applying graded horizontal test loads and synchronously monitoring displacement, parameters such as horizontal foundation bed coefficients distributed along the depth are obtained, a design scheme (such as built-in depth) is optimized, and follow-up construction is guided. According to the method, retaining structure construction equipment and test equipment are integrated, the construction process is converted into a large-scale in-situ test field with direct drive design optimization, the overall performance is verified through tests firstly, then time sequence reconstruction of a design scheme is decided, a dynamic design closed loop is achieved from the source of design decision information, and the design efficiency is improved. And data support is provided for advanced identification and control of slope engineering risks.

Description

Technical Field

[0001] This invention belongs to the field of in-situ testing technology in geotechnical engineering, and relates to a method and system for conducting horizontal load tests on retaining structures in slope engineering. In particular, it is an in-situ testing method and system used to optimize the design scheme and guide subsequent construction when the permanent foundation of the retaining structure has not yet been constructed and the design scheme of the retaining structure is yet to be determined. Background Technology

[0002] In slope engineering, the horizontal subgrade coefficient and horizontal bearing capacity of retaining structures (such as anti-slide piles) are important design parameters. Currently, obtaining these parameters mainly relies on two methods: one is to determine the values ​​based on geological survey reports and empirical formulas, but this method has significant uncertainties, often leading to conservative designs or inherent risks; the other is to conduct traditional horizontal load tests on retaining structures separately near the engineering site. This method requires the construction of independent reaction systems (such as anchor piles and reaction beams), which is not only time-consuming and labor-intensive, but also the representativeness of the test results is affected by geological spatial variability and differences in construction disturbances, impacting the accuracy of design parameters and potentially leading to design risks or waste.

[0003] To overcome the aforementioned shortcomings, the industry has begun to explore technical approaches that combine construction and exploration. For example, increasing the width of anti-slide piles can form anti-slide walls. Patent document CN109898520B discloses a "sinking wall construction method," which, through a controllable sinking wall construction method, can construct a stable trench space, providing a construction solution for the efficient construction of retaining structures (such as anti-slide walls). Chinese patent application CN202410789073.7A describes a "construction and exploration method for the horizontal subgrade coefficient of the passive zone of a foundation pit." This method combines the aforementioned sinking wall construction with in-situ testing. After the permanent foundation of the retaining wall in the foundation pit is constructed, the horizontal subgrade coefficient of the soil in the passive zone of the foundation pit is tested by loading the retaining structure on the inner side of the foundation pit. Although this method achieves a combination of construction and exploration, its testing, like the aforementioned traditional tests, occurs after the permanent foundation of the retaining structure has been constructed and the boundary conditions at the bottom of the foundation have been fixed. This results in the loss of the possibility of using the test results to optimize the foundation design of the retaining structure (such as the embedment depth). Therefore, how to obtain reliable design parameters before the construction of the permanent foundation of the slope retaining structure remains a technical problem that urgently needs to be solved.

[0004] At a deeper level, these limitations reflect a more fundamental dilemma in the field of geotechnical engineering: the information upon which design decisions rely is uncertain at its source (which can be simply referred to as uncertainty in the source of design decision information). For a long time, the acquisition of design parameters has heavily relied on limited and discrete exploration points (such as boreholes) conducted before construction, using indirect inference—"from point to surface, from borehole to volume"—to grasp the characteristics of large-scale, heterogeneous soil and rock masses. This cognitive path inevitably contains "blind spots between boreholes" and the resulting parameter uncertainties. In recent years, the development of measurement-while-drilling technology and geophysical exploration methods has provided new avenues for improving the resolution and continuity of exploration. However, these methods essentially still fall into the category of "indirect inference." To address this uncertainty, the engineering community has developed various design methodologies: (1) deterministic methods introduce safety factors to accommodate the unknown, but often lead to conservative design schemes; (2) probabilistic methods attempt to quantify uncertainty, but their reliability is limited by the accuracy of the input parameter probability model, which in turn originates from the incomplete geological survey information; (3) the observation method regards the construction process as a verification and learning phase, dynamically adjusting the design through monitoring feedback, thus achieving a dynamic closed loop between design and construction, representing a significant advancement in engineering methodology. However, the adjustment of the observation method is essentially a passive feedback after the risk manifests (such as significant displacement development), and the initial geological model on which its decisions are based still originates from incomplete geological survey information. Therefore, how to alleviate the fundamental bottleneck of "uncertainty at the source of design decision information" has become a key issue in improving the reliability of the entire geotechnical engineering technology system. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a test method and system that can conduct horizontal load tests before the construction of permanent foundations for slope retaining structures, and dynamically optimize the design scheme based on the test results to guide subsequent construction.

[0006] To address the aforementioned technical problems, this invention is based on the "a method for constructing a sinking wall" disclosed in patent document CN109898520B. By introducing two synergistic technical features, namely "detachable temporary vertical support components" and "dynamic design window period," the traditional "survey-design-construction" process for slope retaining structures is reconstructed.

[0007] The "dynamic design window" is a crucial stage in the construction of the retaining structure. During this stage, the retaining structure has reached the test elevation under the control of the sinking support system and independently bears its entire vertical load by installing detachable temporary vertical support components, thus switching it from "controlled sinking construction mode" to "in-situ testing mode." Simultaneously, the permanent foundation of the retaining structure has not yet been constructed, and the bottom boundary conditions have not yet solidified, making it possible to optimize the design scheme of the retaining structure using in-situ test data.

[0008] The core of this invention lies in systematically incorporating horizontal load testing as an in-situ verification method within the dynamic design window. At this time, the retaining structure is in a critical state where the permanent foundation boundary conditions are undetermined and the design scheme can be optimized. To ensure the safety and accuracy of the test in this state, this invention introduces a "detachable temporary vertical support component" as a dedicated stabilization measure during the test period. During the dynamic design window, horizontal load tests are conducted on the actual slope retaining structure to obtain its test load and displacement response data, thereby transforming the construction process into a large-scale in-situ test field. The resulting comprehensive test results provide a direct and reliable basis for optimizing the retaining structure design scheme. Thus, the construction process is no longer limited to a single sinking operation but simultaneously integrates the pre-construction in-situ verification function, and can drive the optimization of the design scheme in real time based on the verification results.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides a method for testing the horizontal load of a slope retaining structure. The method is performed in a construction trench formed by excavation, wherein retaining structures are provided on the sides of the trench, and a retaining structure is located within the trench between the retaining structures. The retaining structure is controlled by a sinking support system to sink to the test elevation with its bottom suspended, forming a working space between itself and the trench bottom. The sinking support system consists of support columns erected at the trench bottom and jacks installed on top of the support columns. The method is characterized by including the following steps:

[0011] S1. Initiating a dynamic design window: After the retaining structure is lowered to the test elevation by the sinking support system, detachable temporary vertical support members are spaced apart at the bottom of the retaining structure within the working space, so that the detachable temporary vertical support members replace the sinking support system and bear all the vertical loads of the retaining structure. The dynamic design window refers to the stage in which all the vertical loads of the retaining structure are borne by the detachable temporary vertical support members. During the dynamic design window, the permanent foundation of the retaining structure has not yet been constructed.

[0012] S2. Graded Loading and Synchronous Monitoring: The reaction force is provided by the soil and rock behind the retaining structure. A graded horizontal test load is applied to the retaining structure using a controllable loading support rod located between the loading side of the retaining structure and the retaining structure. The test load is transferred to the retaining structure using a force transmission rod located between the retaining structure and the retaining structure, and then transferred from the retaining structure to the soil and rock behind the retaining structure. The load applied by the controllable loading support rod, the load transmitted by the force transmission rod, and the displacement response of the retaining structure under the test load are monitored synchronously. The loading and unloading of the test are controlled according to a preset safety criterion.

[0013] S3. Parameter Acquisition and Design Optimization: Based on the test data of the horizontal test load and displacement response, determine the horizontal bearing design parameters of the retaining structure, and generate an optimized design scheme for the retaining structure to guide subsequent construction based on the horizontal bearing design parameters;

[0014] S4. End the dynamic design window: Stop loading and unload the horizontal test load, use the sinking support system to lift the retaining structure so that the sinking support system bears all the vertical load of the retaining structure, and then remove the detachable temporary vertical support components.

[0015] It should be noted that, in this application, the portion of the support structure located below the potential sliding surface is referred to as the "embedded section" (i.e., the anchored section); the portion located above the potential sliding surface is referred to as the "non-embedded section" (i.e., the loaded section).

[0016] Specifically, the retaining structure can be constructed in segments along its depth. For example, in the non-embedded section of the retaining structure, the retaining structure can be made of sheet piles; in the embedded section of the retaining structure, the retaining structure should preferably be made of wet-mixed shotcrete or wet-mixed shotcrete with steel mesh; the retaining structure is an anti-slide wall or anti-slide pile; the retaining structure has an internal cavity structure; the loading side is the side of the retaining structure that bears the horizontal test load, which is determined according to a preset loading scheme; the force transmission rod can be made of steel structural members, or a self-locking hydraulic jack in a hydraulically locked or mechanically locked state; the controllable loading support rod is located between the loading side of the retaining structure and the retaining structure, wherein the controllable loading support rod is located in the non-embedded section of the retaining structure; the force transmission rod is located between the retaining structure and the retaining structure, wherein the force transmission rod is located in the non-loaded side of the non-embedded section and the embedded section of the retaining structure.

[0017] The controllable loading support rod includes a drive unit, an actuator, and a force sensor. The drive unit receives control signals and adjusts energy output; the actuator is connected to the drive unit and is driven by the drive unit to generate thrust to apply the test load; the force sensor monitors the applied load in real time.

[0018] The actuator, drive unit, and force sensor of the controllable loading support rod can be implemented in various forms:

[0019] (1) Actuator and drive unit: The actuator can be implemented in the form of a hydraulic cylinder or a screw jack driven by a servo motor and a reducer. Preferably, when a hydraulic cylinder is used as the actuator, the drive unit has an oil pump, a motor for driving the oil pump, an oil tank and an electro-hydraulic control valve. By working in conjunction with a high-precision pressure sensor, stable control of the supporting shaft force can be achieved. When the pressure drops due to creep in the rock and soil, oil is added to maintain a constant pressure, which meets the requirements of the slow sustained load method test.

[0020] (2) Force sensor: A high-precision hydraulic pressure sensor or a high-precision strain load sensor can be used. The sensor is directly connected in series in the loading path to measure the test load applied by the controllable loading support rod in real time and accurately.

[0021] The force transmission rod is a rigid rod with a force sensor. The force sensor can be a high-precision strain gauge load cell. The sensor is directly connected in series in the load transmission path to measure the test load transmitted by the force transmission rod in real time and accurately.

[0022] In a preferred embodiment of the present invention, the controllable loading support rod and the force transmission rod are multifunctional support rods with rollers, hydraulic pins, and self-locking hydraulic jacks. During the controlled sinking of the support structure, the multifunctional support rod is located between the support structure and the retaining structure, used to transmit and balance the lateral pressure of the soil and rock and control the sinking friction. During the dynamic design window, it functions as the controllable loading support rod and the force transmission rod, respectively. The hydraulic jack of the controllable loading support rod is in an unlocked state allowing extension and retraction, the roller of the controllable loading support rod is in a free-rotating state, the hydraulic jack of the force transmission rod is in a locked state prohibiting extension and retraction, and the roller of the force transmission rod is in a locked state. The self-locking hydraulic jack integrates an oil pump, a motor for driving the oil pump, an oil tank, an electro-hydraulic control valve, a hydraulic cylinder, and a hydraulic lock. The hydraulic pin is used to lock the roller.

[0023] Specifically, the jacks in the sinking support system are bidirectional jacks, or a system composed of unidirectional jacks that control the lifting and lowering of the support column respectively; the detachable temporary vertical support component is set independently of the sinking support system that controls the sinking of the retaining structure, so that the sinking support system is in an unloaded state during the test, thereby protecting the sinking support system from the influence of the horizontal test load; the detachable temporary vertical support component is a hydraulic support or a temporary support structure composed of multiple rigid blocks stacked together; the rigid blocks are steel blocks or precast concrete blocks; the detachable temporary vertical support component is arranged according to the estimated horizontal test load and the self-weight of the retaining structure.

[0024] Specifically, the displacement response of the retaining structure in step S2 under the test load includes the top displacement of the retaining structure, the rotation angle, and the horizontal displacement of the retaining structure along the depth.

[0025] The test method controls the loading and unloading of the test according to preset safety criteria. These safety criteria aim to protect the safety of the support structure and the surrounding environment, ensuring the test is conducted within a controllable range. One or more safety criteria are rationally selected and set based on the engineering safety level, the sensitivity of the surrounding environment, and the test objectives; for example, including but not limited to:

[0026] (1) Preset displacement response threshold criterion: The displacement response of the support structure (such as the displacement response of a specific monitoring point) reaches the preset allowable value;

[0027] (2) Stiffness characteristic criterion: The load-displacement response curve of the retaining structure shows an inflection point;

[0028] (3) Load instability criterion: The test load cannot maintain stability;

[0029] (4) Preset load threshold criterion: The applied horizontal test load reaches the preset limit value;

[0030] (5) Comprehensive judgment criteria: Judgment is made based on the combination logic of multiple parameters such as displacement response change rate and load change rate.

[0031] As a preferred embodiment of the aforementioned safety criteria, the preset displacement response threshold criterion, stiffness characteristic criterion, load instability criterion, and preset load threshold criterion are adopted. Specifically, when any of the following conditions are detected, the controllable loading support rod is immediately stopped from loading and the test load is unloaded in stages:

[0032] (1) The displacement response of the support structure reaches the preset allowable value;

[0033] (2) The load-displacement response curve of the retaining structure shows an inflection point;

[0034] (3) The test load could not be maintained stably;

[0035] (4) The test load reaches the preset limit value.

[0036] Specifically, the horizontal bearing design parameters mentioned in step S3 include the horizontal subgrade coefficient distributed along the depth of the retaining structure's embedded section and the critical load of the retaining structure.

[0037] Specifically, the step S3 of generating an optimized design scheme for the retaining structure to guide subsequent construction refers to determining technical parameters to guide subsequent construction, thereby optimizing the design scheme of at least one of the foundation system, main structure system, and anchoring system of the retaining structure, including:

[0038] (1) Foundation System: Determine the embedment depth and / or determine the technical parameters for reinforcing the soil and rock mass in the embedded section of the retaining structure. When the horizontal subgrade coefficient does not meet the design requirements, grouting reinforcement can be carried out on the soil and rock mass in the embedded section of the retaining structure;

[0039] (2) Main structural system: Based on the horizontal bearing design parameters, determine whether to implement post-reinforcement measures for the main structural system and their technical parameters. The post-reinforcement measures include: when the main structural system has an internal cavity structure, placing a post-reinforcement structure (such as a steel cage or steel section) or applying vertical prestress within the internal cavity;

[0040] (3) Anchoring system: Determine whether to install anchoring components, and determine the location, angle and design tonnage technical parameters of the anchoring components.

[0041] The main structural system is pre-installed with ducts for grouting and reinforcing the foundation after the test, as well as ducts for installing anchoring components after the test.

[0042] Secondly, the present invention also provides a test system for implementing the above-described method. The test system includes a construction trench formed by excavation, a retaining structure disposed on the side of the construction trench, a support structure located within the trench between the retaining structures and for which permanent foundations have not yet been constructed, a sinking support system for the support structure, a controllable loading support rod located between the loading side of the support structure and the retaining structure, a force transmission rod located between the support structure and the retaining structure, and a displacement monitoring system for monitoring the displacement response of the support structure. The sinking support system consists of a support column erected at the bottom of the trench and a jack installed on the top of the support column. The sinking support system is used to control the support structure. The system is lowered to the test elevation, creating a working space between the bottom of the retaining structure and the bottom of the trench. The loading side is the side of the retaining structure that bears the horizontal test load. The controllable loading support rod is used to apply the test load using the reaction force provided by the soil and rock behind the retaining structure. The force transmission rod is used to transfer the test load to the retaining structure, and then from the retaining structure to the soil and rock behind the retaining structure. The displacement monitoring system has a displacement sensor. The controllable loading support rod has a drive unit, an actuator, and a force sensor. The force transmission rod is a rigid rod and has a force sensor. The test system also includes:

[0043] (1) A detachable temporary vertical support component is located at intervals between the bottom of the support structure and the bottom of the trench within the working space, and is used to replace the sinking support system to bear all the vertical loads of the support structure;

[0044] (2) The control and analysis module is communicatively connected to the drive unit and force sensor of the controllable loading support rod, the force sensor of the force transmission rod, and the displacement sensor of the displacement monitoring system. It is used to control the controllable loading support rod to apply graded horizontal test loads to the retaining structure, synchronously acquire displacement response data, load data collected by the force sensor of the controllable loading support rod and the force sensor of the force transmission rod, control the loading and unloading of the test according to the preset safety criteria, and calculate and output the horizontal bearing design parameters for the dynamic design of the retaining structure based on the horizontal test load-displacement response data.

[0045] Specifically, the retaining structure is one of sheet piles, wet-mixed shotcrete, or wet-mixed shotcrete with reinforced mesh; the retaining structure located in the non-embedded section of the retaining structure is sheet piles; the retaining structure located in the embedded section of the retaining structure is wet-mixed shotcrete or wet-mixed shotcrete with reinforced mesh; the retaining structure is an anti-slide wall or anti-slide pile; the retaining structure has an internal cavity structure; the retaining structure has channels for installing anchoring components; the retaining structure has channels for grouting reinforcement of the foundation; the jacks at the top of the support column are bidirectional jacks, or a system composed of unidirectional jacks that control the lifting and lowering of the support column respectively; the drive unit has an oil pump, a motor for driving the oil pump, an oil tank, and an electro-hydraulic control valve, or a servo motor and a reducer; the actuator is a hydraulic cylinder or a screw jack driven by the servo motor and reducer; the force sensor of the controllable loading support rod is a pressure sensor or a load sensor; the force sensor of the force transmission rod is... The load sensor is present; the force transmission rod has a self-locking hydraulic jack in a hydraulically locked or mechanically locked state; the controllable loading support rod is located between the loading side of the retaining structure and the retaining structure, wherein the controllable loading support rod is located in the non-fixed section of the retaining structure; the force transmission rod is located between the retaining structure and the retaining structure, wherein the force transmission rod is located in the non-loaded side and the fixed section of the non-fixed section of the retaining structure; the displacement monitoring system has a displacement sensor for monitoring the top displacement and rotation angle of the retaining structure and a fixed inclinometer for monitoring the horizontal displacement of the retaining structure along the depth, wherein the fixed inclinometer is located in an inclinometer tube rigidly connected to the retaining structure; the detachable temporary vertical support component is a hydraulic support or a temporary support structure composed of multiple rigid blocks stacked together; the rigid block is a steel block or a precast concrete block; the horizontal bearing design parameters include the horizontal subgrade coefficient distributed along the depth of the fixed section of the retaining structure and the critical load of the retaining structure.

[0046] In a preferred embodiment of the present invention, the controllable loading support rod and the force transmission rod are multifunctional support rods with rollers, hydraulic pins, and self-locking hydraulic jacks. The hydraulic pins are used to lock the rollers. In the locked state, the rollers form rigid contact with the support structure and the retaining structure to transmit loads. The multifunctional support rod is used to load test loads when the self-locking hydraulic jack is in an unlocked state that allows extension and retraction and the rollers are in a free rotation state. The multifunctional support rod is used to transmit test loads when the self-locking hydraulic jack is in a locked state that prohibits extension and retraction and the rollers are all locked.

[0047] Specifically, the control and analysis module is a distributed control system consisting of an industrial control computer and a field controller connected via a wireless communication network. The field controller is connected via a wired connection to the drive unit, force sensor, and force sensor of the controllable loading support rod. The field controller is also connected via a wired connection to the displacement sensor of the displacement monitoring system. Both the industrial control computer and the field controller have executable programs. The control and analysis module is used for:

[0048] (1) The industrial control computer is used to receive displacement response data collected by the displacement sensor of the displacement monitoring system, load data collected by the controllable loading support rod force sensor and the force transmission rod force sensor through the wireless communication network.

[0049] (2) The industrial computer is used to send control commands to the field controller through the wireless communication network according to the preset loading scheme;

[0050] (3) The field controller is used to perform closed-loop control according to the received instructions, and drive the controllable loading support rod to perform graded loading and load maintenance;

[0051] (4) The industrial control computer is used to draw load-displacement response curves and determine the critical load of the retaining structure based on the load data collected by the load sensor of the controllable load support rod at each depth and the displacement response data of the retaining structure obtained by the displacement monitoring system at the corresponding depth.

[0052] (5) The industrial control computer is used to calculate and output the horizontal subgrade coefficient distributed along the depth of the retaining structure based on the load data collected by the load sensor of the force transmission rod at each depth of the retaining structure and the displacement response data of the retaining structure at the corresponding depth obtained by the displacement monitoring system.

[0053] It should be noted that a wireless communication network is used to adapt to the complex environment, difficult wiring, and easily damaged cables at the construction site of the slope retaining structure. The wireless communication network is used to transmit high-level control commands (such as target load values) and monitoring data, while real-time low-level closed-loop control (such as pressure regulation and sampling) is executed by the field controller. This architecture utilizes the flexibility of wireless technology while ensuring real-time control and security through field closed-loop control. The horizontal subgrade coefficient distributed along the depth of the retaining structure's embedded section is directly calculated based on the Winkler elastic foundation beam model.

[0054] Specifically, the preset safety criteria are used to control the controllable loading support rod to immediately stop loading and remove the test load in stages when the displacement response of the support structure reaches a preset allowable value, or the load-displacement response curve of the support structure shows an inflection point, or the test load cannot be maintained stably, or the test load reaches a preset limit value.

[0055] The beneficial effects of this invention are as follows:

[0056] (1) Technical effect: Achieve efficient, low-cost, and highly reliable in-situ testing

[0057] This invention utilizes a construction trench built using a controllable sinking wall construction method. By deeply integrating horizontal load tests on slope retaining structures and temporary stabilization measures with this construction method, and using the retaining structure as a force transmission medium, the underlying soil and rock mass provides the reaction force. This eliminates the need for a separate dedicated reaction system (such as anchor piles and reaction beams), significantly saving time and cost. Based on this, horizontal load tests are conducted on the actual retaining structure of the slope engineering. Unlike traditional retaining structure horizontal load tests that obtain the horizontal subgrade coefficient through inversion analysis, this invention directly calculates the horizontal subgrade coefficient distributed along the depth of the retaining structure's embedded section using load data collected by force sensors on the force transmission rods at various depths of the embedded section and displacement response data obtained by a displacement monitoring system at the corresponding depths. This significantly improves the amount and reliability of the test data, providing important guidance for the optimized design of subsequent construction.

[0058] (2) Design effect: Achieve dynamic design closed loop from the source of design decision information, and proactively identify and control potential risks in slope engineering.

[0059] This invention establishes a "dynamic design window" and introduces "removable temporary vertical support components" as a stability guarantee during testing, systematically placing horizontal load testing as an in-situ verification method before the construction of the permanent foundation of the retaining structure. This temporal reconstruction transforms the information source upon which design decisions rely from discrete, inferred geological survey data to directly acquired in-situ verification data of the engineering entity and its revealed overall bearing capacity. Based on the reliable design decision information source of the actual overall horizontal bearing capacity design parameters obtained from the tests, designers can scientifically and dynamically optimize and determine key design schemes such as the embedment depth of the retaining structure, the main structure, and the anchoring system. This effectively alleviates the over-reliance on incomplete and indirect geological survey information in design decisions, avoids over-design while ensuring safety, and achieves the direct driving of design optimization by obtaining holistic in-situ response data from the design decision information source, thus proactively identifying and controlling potential risks in slope engineering.

[0060] (3) Methodological effect: Relying on the innovation of construction methods, through verification, design and construction collaboration, the bottleneck of information source for design decision-making is effectively alleviated.

[0061] This invention is not only a specific experimental technique, but also an implementable example of the methodology of "transforming the construction process into a large-scale in-situ test field that directly drives design optimization." Based on innovations in construction methods, it proposes a systematic solution for dynamic design of slope retaining structures from the source of design decision information. It adopts an integrated design of construction and testing equipment, and through the efficient collaboration of in-situ verification, dynamic design, and the construction carrier, it transforms the construction trench environment formed by the controllable settlement wall construction method from a simple building space into an "in-situ test field" that directly serves design decisions. This makes in-situ verification testing a basis for verifying overall bearing capacity and design decisions during construction, rather than merely serving as post-construction design verification. Thus, it revolutionizes the traditional fragmented process of surveying, design, and construction, effectively alleviating the fundamental bottleneck of "uncertainty at the source of design decision information," and providing reliable data support for slope engineering risk control. Attached Figure Description

[0062] Figure 1 This is a schematic diagram of the construction environment on which the experimental method of this invention is based;

[0063] Figure 2 This is a side view of the construction environment on which the test method of this invention is based;

[0064] Figure 3 This is a schematic elevation view of the controllable loading support rod, force transmission rod, and inclination monitoring arrangement of the present invention.

[0065] Figure 4 This is a top view schematic diagram of the controllable loading support rod, force transmission rod, and inclination monitoring arrangement of the present invention.

[0066] Attached reference numerals: 1. Retaining structure; 2. Anti-slide wall; 3. Wall base plate; 4. One-way jack on top of support column; 5. One-way jack on side of support column; 6. Support column; 70. Multifunctional support rod (equipped with a self-locking hydraulic jack and lockable rollers, installed between the anti-slide wall 2 and the retaining structure 1 during construction to transmit and balance the lateral pressure of the soil and rock and control the settling friction; used as a controllable loading support rod 71 or a force transmission rod 72 during the test phase); 71. Controllable loading support rod (multifunctional support rod 70 that performs loading function during the test phase, self-locking hydraulic jack). 72. Force transmission rod (multi-functional support rod 70 that performs force transmission function during the test phase, with self-locking hydraulic jack in a locked state and roller in a locked state, located between the non-loaded side of the non-fixed section of the anti-slide wall 2 and the retaining structure 1, and between the fixed section of the anti-slide wall 2 and the retaining structure 1); 8. Cantilever reaction member; 9. Rock and soil reinforced under the support column; 10. Inclinometer tube; 11. Detachable temporary vertical support component. Detailed Implementation

[0067] The following detailed description of the test method and system of the present invention, with reference to the accompanying drawings, uses an application scenario of an anti-slide wall on a slope as an example. In this embodiment, the retaining structure is specifically the anti-slide wall body 2.

[0068] 1. Construction of the test environment

[0069] First, based on the test task sheet and design drawings, at the predetermined location on the slope, the construction method described in patent document CN109898520B, "A Method for Constructing a Sinking Wall," was employed. Figure 1 and Figure 2 The diagram shows the construction trench environment upon which the construction test was based. The specific steps are as follows:

[0070] (1) Along the design axis of the anti-slide wall 2, construct the retaining structure 1 on the side of the trench. The retaining structure 1 is constructed in the form of steel sheet piles in the upper soil layer. After the trench is excavated into the rock layer, the lower rock layer is constructed using reinforced mesh and wet shotcrete to form a tight contact surface with the rock mass, which is beneficial for subsequent testing. According to the design drawings, drill holes at the corresponding positions of the support column 6 to extract soil, and then backfill the holes with plain concrete to form the reinforced soil and rock mass 9 under the support column.

[0071] (2) The base slab 3 and initial wall sections of the anti-slip wall 2 are cast on-site (using reinforced concrete structure). The anti-slip wall 2 has an internal cavity structure, the size of which meets the construction requirements of small drilling and grouting machinery. To facilitate subsequent optimization design, the anti-slip wall 2 is pre-configured with conditions for implementing optimization design, including: reserved ducts for subsequent installation of anchoring components, construction ducts for grouting and reinforcing the soil and rock mass of the embedded section of the anti-slip wall 2 within the cavity, and reserved holes for installing vertical prestressing tendons on the base slab 3. An outlet is provided on the base slab 3, forming an outlet channel in conjunction with the cavity structure of the anti-slip wall 2. The cavity structure and various reserved ducts enable flexible implementation of optimization measures such as strengthening the main structure, reinforcing the foundation, or anchoring based on test results after the "dynamic design window period," providing the necessary physical conditions for achieving dynamic design optimization based on test results. For example, if the test reveals that the horizontal subgrade coefficient of the foundation in the embedded section of the anti-slide wall 2 does not meet the design requirements, grouting reinforcement of the foundation can be carried out in the cavity of the anti-slide wall 2 using a small drilling and grouting device through pre-reserved construction channels. A temporary steel truss and a no-roughening, no-removal template are installed inside the cavity. The template is a precast concrete slab with a roughened surface, and connectors are pre-embedded inside, which are fixed to the temporary steel truss by bolts. The temporary steel truss serves several purposes: providing lateral support for the template, replacing construction scaffolding, enhancing the strength and stiffness of the anti-slide wall 2 during testing, and serving as a construction platform for grouting reinforcement of the soil and rock mass in the embedded section of the anti-slide wall 2 within the cavity. Furthermore, the anti-slide wall 2 also has pre-embedded parts for installing the inclinometer tube 10. These pre-embedded parts have bolt holes for connecting to the inclinometer tube 10, providing conditions for the subsequent rigid installation of the inclinometer tube 10.

[0072] (3) A sinking support system is used, specifically a support column 6 erected at the bottom of the excavation trench and a one-way jack 4 and a one-way jack 5 installed on the top of the support column 6, to support the anti-slide wall 2, suspending the bottom of the anti-slide wall 2 in the air, forming a working space at the bottom of the wall, and controlling the sinking of the anti-slide wall 2. The self-weight of the anti-slide wall 2 is transmitted from the cantilever reaction member 8 to the support column 6 via the one-way jack 4 on the top of the support column, and is finally borne by the reinforced soil and rock mass 9 under the support column.

[0073] (4) In the working space at the bottom of the wall, remote-controlled excavation equipment is used to excavate the soil and rock in the trench layer by layer along the direction of the anti-slide wall 2, and transport it out through the excavation channel. When the excavation reaches a certain support column 6, the column is first lifted by the one-way jack 5 on the top side of the support column. After the bottom layer of soil and rock at the bottom of the column is excavated, the column is lowered. Then, the one-way jack 4 on the top of the support column presses down on the column until it settles and stabilizes.

[0074] (5) As the soil and rock mass is excavated, the unidirectional jacks 4 on the top of each support column and the unidirectional jacks 5 on the side of the support column are coordinated and controlled to ensure that the anti-slide wall 2 sinks uniformly and in a controlled manner to the test elevation (this elevation is preliminarily determined based on the geological survey report and experience), thereby creating conditions for entering the "dynamic design window period" and optimizing the design scheme through in-situ testing. Among them, the anti-slide wall 2 sinks a section under the control of the sinking support system and rises a section above the ground.

[0075] (6) During the sinking of the anti-slide wall 2, multi-functional support rods 70 are installed between the anti-slide wall 2 and the retaining structure 1 from bottom to top. During installation, adjacent multi-functional support rods 70 on the same side are connected with vertical connecting rods to form a vertical rod group. The self-weight of the vertical rod group is transferred to the anti-slide wall 2 through the wall base plate 3. During the sinking of the anti-slide wall 2, the installed multi-functional support rods 70 perform the following functions: using their built-in self-locking hydraulic jacks and rollers, they transmit and balance the lateral pressure of the soil and rock on the side of the trench, and control the frictional resistance during the sinking of the anti-slide wall 2. Among them, the self-locking function can improve the safety guarantee capability of the trench wall during construction.

[0076] Thus, through the above steps (1) to (6), a construction tank environment suitable for subsequent horizontal load tests has been constructed.

[0077] 2. Enable the dynamic design window

[0078] After the anti-slide wall 2 has sunk to the test elevation, the sinking operation will be suspended, and the slag at the bottom of the trench will be cleared. If there is groundwater in the trench, drainage equipment must be installed to ensure the orderly conduct of the dynamic design window. The core task at this stage is to safely and reliably convert the anti-slide wall 2 from the "controlled sinking mode" to the "test mode," thereby opening the "dynamic design window."

[0079] (1) Installation of detachable temporary vertical support component 11

[0080] To prevent the sinking support system from becoming unstable under horizontal test loads, this invention specifically introduces a detachable temporary vertical support component 11, independent of the sinking support system. This component, under load, replaces the sinking support system and bears the entire vertical load of the anti-slip wall 2, thus ensuring the sinking support system is unloaded during the test.

[0081] The detachable temporary vertical support component 11 uses a large-tonnage, height-adjustable hydraulic prop with its lower end standing on the bottom of the trench. It is symmetrically spaced below the wall base plate 3 according to the estimated horizontal test load and the self-weight of the anti-slip wall 2. During installation, the hydraulic props are synchronously lifted to ensure their upper ends tightly support the wall base plate 3. During this process, the stress state of the sinking support system (such as the one-way jack 4 on top of the support column) is monitored. When the hydraulic prop has borne the entire vertical load and the sinking support system is completely unloaded, the hydraulic prop is locked, and a mechanical locking device (such as a pin) is used as secondary protection. At this point, the anti-slip wall 2 safely switches from the "controlled sinking mode" to the "test mode," marking the official start of the "dynamic design window." As another alternative implementation, the detachable temporary vertical support members 11 can be placed at predetermined positions at the bottom of the trench in advance. Then, by controlling the sinking support system (such as coordinating the operation of the one-way jacks 4 on the top of each support column), the anti-slip wall 2 can be lowered synchronously and slowly until the wall base plate 3 sits on the detachable temporary vertical support members 11, thereby realizing the transfer of vertical load from the sinking support system to the detachable temporary vertical support members 11.

[0082] (2) Pre-experiment status confirmation and initiation of dynamic design window experiment

[0083] After completing the installation of the detachable temporary vertical support component 11 and transferring the vertical load from the sinking support system to this component, it is necessary to further confirm that the anti-slip wall 2 has obtained stable vertical support. Check whether the reading of the one-way jack 4 on the top of the support column of the sinking support system has returned to zero, and at the same time obtain its positioning status feedback through the pressure sensor installed on the detachable temporary vertical support component 11. After confirming that the anti-slip wall 2 has obtained stable vertical support, mechanically lock the one-way jack 4 on the top of the support column in the retracted state, so that it is disengaged from the cantilever reaction component 8 under force. Figure 3 As shown, this was done to avoid interference with subsequent experiments. The graded loading and synchronous monitoring of the experiment were then initiated.

[0084] 3. Hierarchical loading and synchronous monitoring

[0085] This horizontal load test was conducted within the stated dynamic design window. Based on the preset loading scheme, the loaded and unloaded sides of the horizontal load test for the anti-slip wall 2 were determined. The specific test steps included:

[0086] (1) Installation and debugging of the test system

[0087] During the aforementioned dynamic design window, the experimental system was installed and debugged, as follows:

[0088] 1) Install a displacement monitoring system

[0089] Displacement monitoring points are arranged at the top of the anti-slip wall 2, and displacement sensors (such as high-precision inclinometers or large-range displacement gauges) are installed to monitor the displacement and rotation of the wall top. Inclinometer tubes 10 are fixedly installed in the wall body of the anti-slip wall 2 via bolts, forming a rigid connection between the inclinometer tubes 10 and the wall. A fixed inclinometer is installed inside the inclinometer tubes 10 to monitor the horizontal displacement of the anti-slip wall 2 along its depth. The inclinometer tubes 10 are arranged symmetrically (e.g., ...). Figure 4 As shown in the diagram, the inclinometer data from both sides can be used to verify each other, which helps improve the reliability of the data. After installation, read the initial readings.

[0090] The measurements from the wall-top displacement sensor are directly based on the reference beam as the physical reference; while the monitoring data from the fixed inclinometer are corrected by incorporating the measured values ​​from the wall-top displacement sensor as boundary conditions to obtain the absolute horizontal displacement of the anti-slip wall 2 along its depth. The reference beam is erected on a stable ground unaffected by the test, has sufficient rigidity, and is equipped with sunshade protection facilities.

[0091] 2) Debugging of the control and analysis module

[0092] In this embodiment, the control and analysis module adopts a distributed architecture, consisting of an industrial control computer and field controllers connected via a wireless communication network, to achieve data acquisition and precise control of the experimental process. The wireless communication network uses an industrial-grade wireless protocol.

[0093] a) Specify the controllable loading support rod 71 and the force transmission rod 72

[0094] After the anti-slide wall 2 enters the "dynamic design window period", the industrial control computer sends instructions to each field controller through the wireless communication network according to the preset loading scheme: designating the multi-functional support rod 70 located between the loading side of the non-embedded section of the anti-slide wall 2 and the retaining structure 1 as the "controllable loading support rod 71" to apply the horizontal test load, with its self-locking hydraulic jack in the unlocked state that allows extension and retraction, and the roller in the free rotation state; designating the multi-functional support rod 70 located between the non-loading side of the non-embedded section of the anti-slide wall 2 and the retaining structure 1 and between the embedded section of the anti-slide wall 2 and the side retaining structure 1 as the "force transmission rod 72", locking its self-locking hydraulic jack to the locked state that prohibits extension and retraction, and driving its built-in hydraulic pin to lock its roller, thus forming the force transmission rod 72. The roller in the locked state forms rigid contact with the anti-slide wall 2 and the retaining structure 1 to transmit the load. Thus, the multi-functional support rod 70 during the construction period was designated as the controllable loading support rod 71 and the force transmission rod 72 in the test system according to different instructions.

[0095] It should be noted that the controllable loading support rod 71 and the force transmission rod 72 are mechanically identical. They are labeled differently in the attached drawings to clearly distinguish their different functional roles during the horizontal load test. More importantly, the controllable loading support rod 71 and the force transmission rod 72 are the same physical equipment as the multi-functional support rod 70 installed during construction. This design allows the same equipment to maintain the stability of the trench wall during construction and to perform loading or force transmission functions through different commands during the test, thus achieving integration of construction and testing equipment without the need to reinstall the loading and force transmission equipment for the test.

[0096] b) Field controller: Embedded controller

[0097] In this embodiment, an embedded controller integrated within the multi-functional support rod 70 (i.e., the controllable loading support rod 71 and the force transmission rod 72) is used as the field controller. Each controllable loading support rod 71 and the force transmission rod 72 adopts an electromechanical-hydraulic integrated design. Each controllable loading support rod 71 and the force transmission rod 72 is equipped with rollers and independently includes: an embedded controller used as the field controller, a self-locking hydraulic jack, a high-precision hydraulic pressure sensor, a high-precision strain gauge load sensor, and a hydraulic pin for locking the rollers. They are interconnected through internal circuits and oil circuits and powered by an independent power supply. The self-locking hydraulic jack integrates a miniature oil pump and oil tank, a motor for driving the oil pump, an electro-hydraulic control valve, a hydraulic cylinder, and a hydraulic lock. The independent power supply uses an external battery installed nearby and connected by a wire, or a built-in battery pack. The electromechanical-hydraulic integrated design eliminates the need for external high-pressure oil pipe connections for the controllable loading support rod 71 and the force transmission rod 72, adapting to narrow and dense construction site spaces.

[0098] The hydraulic cylinder of the self-locking hydraulic jack constitutes the actuator; the miniature oil pump and oil tank within the self-locking hydraulic jack, the motor driving the oil pump, and the electro-hydraulic control valve together constitute the drive unit; the high-precision strain gauge load cell and the high-precision hydraulic pressure sensor serve as the force sensors, and the hydraulic lock of the self-locking hydraulic jack is used to lock the hydraulic jack. Alternatively, the actuator can also be a screw jack driven by a servo motor and a reducer. In this embodiment, the drive unit is a servo motor and a reducer, and the force sensor is a load cell.

[0099] c) Data acquisition, transmission, and closed-loop control

[0100] Data Acquisition and Transmission: All sensors in the displacement monitoring system are connected via wired connection to the nearest field controller (i.e., the embedded controller integrated into the controllable loading support rod 71 and force transmission rod 72). The high-precision hydraulic pressure sensor in each controllable loading support rod 71 and force transmission rod 72 is connected to the oil circuit to measure pressure values. The high-precision strain gauge load cell is directly connected in series in the loading path to measure the load values ​​of the controllable loading support rod 71 and force transmission rod 72 in real time and accurately. The embedded controller processes the data collected by the displacement sensors and the high-precision hydraulic pressure sensor and high-precision strain gauge load cell, and then transmits the data in real time to the industrial control computer via a wireless communication network for safety monitoring during the test process and subsequent design parameter calculation and output. Simultaneously, the industrial control computer generates control commands (such as target load values) according to the preset loading scheme and transmits them to each embedded controller via the wireless communication network.

[0101] Closed-loop control: The embedded controller has a built-in control program that reads data collected by high-precision hydraulic pressure sensors and high-precision strain gauge load sensors, compares it with the target commands received from the industrial control computer, and automatically adjusts the pressure of the self-locking hydraulic jack according to the closed-loop control algorithm to achieve precise closed-loop pressure control and stable load maintenance. To ensure test safety, the embedded controller is designed with a communication fault tolerance mechanism. When the wireless communication network is interrupted, the embedded controller's built-in control program automatically identifies the communication fault and maintains the currently applied test load of the controllable loading support rod 71 constant according to the last valid command received before the interruption until communication is restored. Furthermore, the embedded controller has local storage capabilities, and can automatically resume the monitoring data during the interruption after communication is restored, thereby reducing potential safety risks caused by communication failures.

[0102] 3) Test system status verification

[0103] Start the industrial control computer and the embedded controller of the control and analysis module, and run the executable program stored in the industrial control computer and the embedded controller. Connect the industrial control computer to the embedded controller via a wireless communication network. Perform system debugging to confirm that each device is working properly. Check the force applied to the anti-slip wall 2 by the controllable loading support rod 71 and the force transmission rod 72, focusing on confirming that the force on both sides of the anti-slip wall 2 along the direction is in a balanced state, and record the initial axial force values ​​of the controllable loading support rod 71 and the force transmission rod 72 before the start of the test.

[0104] At this point, the test system is ready. The controllable loading support rods, force transmission rods, and inclinometer monitoring setup for the test phase are as follows: Figure 3 , Figure 4As shown, the working principle of the loading-force transmission system in this experiment is as follows: By controlling the controllable loading support rod 71 located between the loading side of the non-embedded section of the anti-slide wall 2 and the retaining structure 1, a horizontal test load is applied to the anti-slide wall 2, and the reaction force is provided by the soil and rock behind the retaining structure 1; the test load is transferred from the anti-slide wall 2 to the retaining structure 1 by using the force transmission rod 72 located between the non-embedded section of the anti-slide wall 2 and the retaining structure 1 and between the embedded section of the anti-slide wall 2 and the retaining structure 1, and then transferred from the retaining structure 1 to the soil and rock behind it, thus forming a complete loading-force transmission system.

[0105] (2) Graded loading of horizontal test load

[0106] Before starting the graded loading, the load-bearing capacity of the controllable loading support rod 71 and the force transmission rod 72 (especially the rollers and the hydraulic pins used to lock the rollers) must be finally checked according to the maximum test horizontal load in the preset loading scheme to confirm that they meet the test requirements. Then, through the control and analysis module program, the controllable loading support rod 71 in the selected test section is controlled to apply a horizontal test load to the anti-slip wall 2 according to the preset graded loading scheme (such as the slow sustained load method). The loading process should be slow and smooth. During the test loading process, the control and analysis module, based on the feedback values ​​of the high-precision hydraulic pressure sensor and the high-precision strain gauge load sensor, drives the hydraulic jack in real time to perform micro-amplitude expansion and contraction compensation to maintain a constant applied test load. During the graded loading process, the next level of loading can only be carried out after the displacement response of the anti-slip wall 2 under each load level meets the stability standard specified in the test task.

[0107] (3) Synchronous monitoring and data acquisition

[0108] During the hierarchical loading process, the following three aspects of data are collected simultaneously:

[0109] 1) Load data: Load values ​​collected by high-precision hydraulic pressure sensor and high-precision strain load sensor in controllable loading support rod 71, and load values ​​collected by high-precision strain load sensor in force transmission rod 72.

[0110] 2) Displacement response data of the top of anti-slip wall 2: including the displacement and rotation of the top of anti-slip wall 2;

[0111] 3) Horizontal displacement data of the anti-slip wall 2 along the depth: The horizontal displacement of the anti-slip wall 2 along the depth is monitored by a fixed inclinometer in the inclinometer tube 10 installed on the anti-slip wall 2.

[0112] The load and displacement response data collected above will be used for subsequent acquisition of horizontal bearing design parameters and design optimization.

[0113] (4) Test safety control and termination

[0114] During the test, the load and displacement data were monitored in real time by the industrial control computer to protect the safety of the anti-slip wall 2, which has not yet had its permanent foundation constructed, and the surrounding environment. To ensure test safety, loading was immediately stopped and the test load was gradually removed if any of the following conditions occurred:

[0115] 1) The displacement response of the anti-slip wall 2 reaches the preset allowable value;

[0116] 2) The load-displacement response curve of the anti-slip wall 2 shows an inflection point;

[0117] 3) The test load cannot be maintained stably;

[0118] 4) The test load reaches the preset limit value.

[0119] The preset allowable values ​​can be reasonably determined based on the safety level of the slope retaining structure, the protection requirements of the surrounding environment, the provisions of relevant specifications, and the purpose of the test. The appearance of an inflection point in the load-displacement response curve indicates a significant change in the stiffness of the anti-slide wall 2, suggesting that the anti-slide wall 2 may enter the yielding or instability stage. This is an important criterion for controlling test risks and preventing uncontrollable deformation of the anti-slide wall 2.

[0120] 4. Parameter Acquisition and Design Optimization

[0121] (1) Data Processing and Acquisition of Horizontal Bearing Capacity Design Parameters: The industrial control computer processes and analyzes the collected load-displacement response data to obtain horizontal bearing capacity design parameters for optimization design. Specifically, this includes:

[0122] 1) Determination of the critical load of the retaining structure: Based on the load data collected by the high-precision strain gauge load sensor inside the controllable loading support rod 71, and the displacement data of the top of the anti-slip wall 2 and the horizontal displacement along the depth obtained by the displacement monitoring system, for each controllable loading support rod 71, the relationship curve between its horizontal test load and the displacement at the contact point between the support rod and the anti-slip wall 2, as well as the corresponding load-displacement gradient curve, are plotted. Based on the characteristics of the above curves and with reference to relevant industry test specifications (such as the "Technical Specification for Testing of Building Foundation Piles" JGJ 106, etc.), the critical load of the anti-slip wall 2 is analyzed and determined.

[0123] 2) Direct calculation of the horizontal subgrade coefficient: Based on the load data collected by the high-precision strain gauge load sensor in the force transmission rod 72 of the anti-slip wall 2 embedded section and the horizontal displacement data of the anti-slip wall 2 along the depth obtained by the displacement monitoring system, a load-displacement relationship curve along the depth is plotted; according to the preset target design load value, the horizontal displacement value corresponding to the design load value is read on the load-displacement curve; according to the Winkler elastic foundation beam model, the target design load value is divided by its corresponding horizontal displacement value to directly calculate the horizontal subgrade coefficient at that depth, thereby obtaining the horizontal subgrade coefficient distributed along the depth of the anti-slip wall 2 embedded section.

[0124] The obtained critical load and the horizontal subgrade coefficient distributed along the depth are the horizontal bearing capacity design parameters that drive subsequent optimization design.

[0125] (2) Design Optimization: Based on the obtained horizontal bearing capacity design parameters, the preliminary design scheme for the anti-slip wall 2 is checked and optimized to determine the technical parameters guiding subsequent construction. This includes the following:

[0126] 1) Foundation system: Based on the horizontal bearing design parameters obtained from the experiment, demonstrate and determine the embedment depth;

[0127] 2) Main structural system: Remove the temporary steel truss installed in the cavity of the wall, and based on the test results, take reinforcement measures such as placing a steel cage and pouring concrete in the cavity, determine the reinforcement parameters of the steel cage and the concrete strength grade, and realize the need to enhance the stiffness and strength of the wall.

[0128] 3) Anchoring system: Based on the test results, determine the anchoring system and, in conjunction with the location of the pre-reserved holes on the anti-slip wall 2 for installing prestressed anchor cables, determine the specific location, angle, and design tonnage technical parameters of the anchoring components.

[0129] 5. End the dynamic design window

[0130] After completing the tiered loading required by the preset loading scheme, the loading is stopped and the horizontal test load is removed in stages. Then, the detachable temporary vertical support components are dismantled, the dynamic design window ends, and the construction phase begins.

[0131] (1) Removal of Temporary Measures and End of Dynamic Design Window: First, the monitoring equipment used during the test is removed, including the inclinometer tube 10 fixed to the anti-slip wall 2 and its internal fixed inclinometer. Second, the industrial control computer sends instructions to each of the embedded controllers via the wireless communication network to restore the controllable loading support rod 71 and the force transmission rod 72 to the multi-functional support rod 70 used during the construction period. Finally, before removing the detachable temporary vertical support component 11, the one-way jack 4 on top of the support column needs to be unlocked to restore its working state, and the sinking support system needs to be functionally checked to ensure its normal operation. Subsequently, the wall base plate 3 is detached from the temporary support component 11 by re-lifting the one-way jack 4 on top of the support column, thereby transferring all the vertical load of the anti-slip wall 2 from the temporary support component 11 to the sinking support system. After confirming that the load transfer is correct, the detachable temporary vertical support component 11 is removed. At this point, the "dynamic design window" officially ends. The anti-slip wall 2 switches from "experimental mode" back to "controlled sinking construction mode" supported by the sinking support system.

[0132] (2) Construction execution design scheme: Based on the design scheme determined by dynamic design, carry out permanent foundation construction of anti-slip wall 2 (such as cleaning the bottom of the trench and backfilling the bottom concrete), main structure system adjustment construction, backfilling concrete construction between the embedded section and the retaining structure 1, backfilling sand and gravel construction between the non-embedded section and the retaining structure 1, and installation of prestressed anchor cables, etc.

Claims

1. A method for testing the horizontal load of a slope retaining structure, performed in a construction trench formed by excavation, wherein retaining structures are provided on the sides of the trench, and a retaining structure is located between the retaining structures within the trench. The retaining structure is controlled by a sinking support system to sink to the test elevation with its bottom suspended, forming a working space between itself and the trench bottom. The sinking support system consists of support columns erected at the bottom of the trench and jacks installed on top of the support columns, characterized by including the following steps: S1. Initiating a dynamic design window: After the retaining structure is lowered to the test elevation by the sinking support system, detachable temporary vertical support members are spaced apart at the bottom of the retaining structure within the working space, so that the detachable temporary vertical support members replace the sinking support system and bear all the vertical loads of the retaining structure. The dynamic design window refers to the stage in which all the vertical loads of the retaining structure are borne by the detachable temporary vertical support members. During the dynamic design window, the permanent foundation of the retaining structure has not yet been constructed. S2. Graded Loading and Synchronous Monitoring: The reaction force is provided by the soil and rock behind the retaining structure. A graded horizontal test load is applied to the retaining structure using a controllable loading support rod located between the loading side of the retaining structure and the retaining structure. The test load is transferred to the retaining structure using a force transmission rod located between the retaining structure and the retaining structure, and then transferred from the retaining structure to the soil and rock behind the retaining structure. The load applied by the controllable loading support rod, the load transmitted by the force transmission rod, and the displacement response of the retaining structure under the test load are monitored synchronously. The loading and unloading of the test are controlled according to a preset safety criterion. S3. Parameter Acquisition and Design Optimization: Based on the test data of the horizontal test load and displacement response, determine the horizontal bearing design parameters of the retaining structure, and generate an optimized design scheme for the retaining structure to guide subsequent construction based on the horizontal bearing design parameters; S4. End the dynamic design window: Stop loading and unload the horizontal test load, use the sinking support system to replace the detachable temporary vertical support member to bear all the vertical load of the retaining structure, and then remove the detachable temporary vertical support member.

2. The method for testing horizontal loads on slope retaining structures according to claim 1, characterized in that, The retaining structure is an anti-slide wall or anti-slide pile; the retaining structure has an internal cavity structure; in the non-embedded section of the retaining structure, the retaining structure is a steel sheet pile; in the embedded section of the retaining structure, the retaining structure is wet-mixed shotcrete or reinforced mesh wet-mixed shotcrete; the jacks at the top of the supporting column are bidirectional jacks, or a system composed of unidirectional jacks; the detachable temporary vertical support component is a hydraulic support or a temporary support structure composed of multiple rigid blocks stacked together; the detachable temporary vertical support component is set independently of the sinking support system that controls the sinking of the retaining structure; the detachable temporary vertical support component is arranged according to the estimated horizontal test load and the self-weight of the retaining structure; the controllable loading support rod has a drive unit, an actuator, and a force sensor. The force transmission rod is a rigid rod and has a force sensor; the loading side is determined according to a preset loading scheme; the controllable loading support rod is located between the loading side of the retaining structure and the retaining structure, wherein the controllable loading support rod is located in the non-fixed section of the retaining structure; the force transmission rod is located between the retaining structure and the retaining structure, wherein the force transmission rod is located in the non-loaded side and the fixed section of the non-fixed section of the retaining structure; the displacement response of the retaining structure under the test load in step S2 includes the top displacement, rotation angle, and horizontal displacement of the retaining structure along the depth; the control of the loading and unloading of the test according to the preset safety criteria in step S2 means that when any of the following situations occur, loading is immediately stopped and the test load is unloaded in stages: (1) The displacement response of the support structure reaches the preset allowable value; (2) The load-displacement response curve of the retaining structure shows an inflection point; (3) The test load could not be maintained stably; (4) The test load reaches the preset limit value.

3. The method for testing horizontal loads on slope retaining structures according to claim 2, characterized in that, The drive unit includes an oil pump, a motor for driving the oil pump, an oil tank, and an electro-hydraulic control valve, or includes a servo motor and a reducer; the actuator is a hydraulic cylinder or a screw jack driven by the servo motor and reducer; the force sensor of the controllable loading support rod is a pressure sensor or a load sensor; the force sensor of the force transmission rod is a load sensor; the force transmission rod has a self-locking hydraulic jack in a hydraulically locked or mechanically locked state; the controllable loading support rod and the force transmission rod have embedded controllers; the rigid block is a steel block or a precast concrete block.

4. The method for testing horizontal loads on slope retaining structures according to claim 3, characterized in that, The controllable loading support rod and force transmission rod are multifunctional support rods with rollers, hydraulic pins, and self-locking hydraulic jacks. During the controlled sinking of the retaining structure, the multifunctional support rod is located between the retaining structure and the earth-retaining structure, used to transmit and balance the lateral pressure of the soil and rock and control the sinking friction. During the dynamic design window, it functions as the controllable loading support rod and force transmission rod, respectively. The self-locking hydraulic jack of the controllable loading support rod is in an unlocked state allowing extension and retraction, the rollers of the controllable loading support rod are in a free-rotating state, the hydraulic jack of the force transmission rod is in a locked state prohibiting extension and retraction, and the rollers of the force transmission rod are in a locked state. The self-locking hydraulic jack integrates an oil pump, a motor for driving the oil pump, an oil tank, an electro-hydraulic control valve, a hydraulic cylinder, and a hydraulic lock. The hydraulic pin is used to lock the rollers.

5. The method for testing horizontal loads on slope retaining structures according to claim 1, characterized in that, The horizontal bearing capacity design parameters mentioned in step S3 include the horizontal subgrade coefficient distributed along the depth of the embedded section of the retaining structure and the critical load of the retaining structure; the use of the sinking support system to replace the detachable temporary vertical support member to bear the entire vertical load of the retaining structure in step S4 refers to using the sinking support system to lift the retaining structure, so that the sinking support system bears the entire vertical load of the retaining structure; the generation of an optimized design scheme for the retaining structure to guide subsequent construction in step S3 refers to determining the technical parameters used to guide subsequent construction, so as to optimize at least one system design scheme of the foundation system, main structure system, and anchoring system of the retaining structure, including: (1) Basic system: Determine the embedment depth and / or determine the technical indicators for reinforcing the soil and rock mass of the embedded section of the retaining structure; (2) Main structural system: Determine whether to implement post-strengthening measures for the main structural system, and determine the technical parameters of the post-strengthening measures; (3) Anchoring system: Determine whether to install anchoring components, and determine the location, angle and design tonnage technical parameters of the anchoring components.

6. The method for testing horizontal loads on slope retaining structures according to claim 5, characterized in that, The main structural system is pre-installed with ducts for grouting and reinforcing the foundation after the test, and / or ducts for installing anchoring components after the test; the post-reinforcement measures for the main structural system refer to: when the main structural system has an internal cavity structure, according to the horizontal bearing design parameters, a post-reinforcement structure is placed in the internal cavity, and / or vertical prestress is applied.

7. A horizontal load testing system for a slope retaining structure, the testing system comprising: a construction trench formed by excavation; a retaining structure disposed on the side of the construction trench; a retaining structure located within the trench between the retaining structures and whose permanent foundation has not yet been constructed; a sinking support system for the retaining structure; a controllable loading support rod located between the loading side of the retaining structure and the retaining structure; a force transmission rod located between the retaining structure and the retaining structure; and a displacement monitoring system for monitoring the displacement response of the retaining structure, wherein... The sinking support system consists of support columns erected at the bottom of the trench and jacks installed on top of the support columns. The sinking support system controls the sinking of the retaining structure to the test elevation, creating a working space between the bottom of the retaining structure and the trench bottom. The loading side is the side of the retaining structure that bears the horizontal test load. The controllable loading support rod applies the test load using the reaction force provided by the soil and rock behind the retaining structure. The force transmission rod transmits the test load to the retaining structure, and then from the retaining structure to the soil and rock behind it. The displacement monitoring system has a displacement sensor. The controllable loading support rod has a drive unit, an actuator, and a force sensor. The force transmission rod is a rigid rod and has a force sensor. The test system also includes: (1) A detachable temporary vertical support component is located at intervals between the bottom of the support structure and the bottom of the trench within the working space, and is used to replace the sinking support system to bear all the vertical loads of the support structure; (2) The control and analysis module is communicatively connected to the drive unit and force sensor of the controllable loading support rod, the force sensor of the force transmission rod, and the displacement sensor of the displacement monitoring system. It is used to control the controllable loading support rod to apply graded horizontal test loads to the retaining structure, synchronously acquire displacement response data, load data collected by the force sensor of the controllable loading support rod and the force sensor of the force transmission rod, control the loading and unloading of the test according to the preset safety criteria, and calculate and output the horizontal bearing design parameters for the dynamic design of the retaining structure based on the horizontal test load-displacement response data.

8. The horizontal load testing system for slope retaining structures according to claim 7, characterized in that, The retaining structure is one of sheet piles, wet-mixed shotcrete, or wet-mixed shotcrete with reinforced mesh; the support structure is an anti-slide wall or anti-slide pile; the support structure has channels for installing anchoring components; the support structure has channels for grouting reinforcement of the foundation; the jacks at the top of the supporting columns are bidirectional jacks, or a system composed of unidirectional jacks; the drive unit has an oil pump, a motor for driving the oil pump, an oil tank, and an electro-hydraulic control valve, or a servo motor and a reducer; the actuator is a hydraulic cylinder or is powered by the servo motor. The controllable loading support rod has a pressure sensor or a load sensor as its force sensor; the force transmission rod has a load sensor as its force sensor; the force transmission rod has a self-locking hydraulic jack in a hydraulically locked or mechanically locked state; the controllable loading support rod is located between the loading side of the support structure and the retaining structure, wherein the controllable loading support rod is located in the non-fixed section of the support structure; the force transmission rod is located between the support structure and the retaining structure, wherein the force transmission rod is located in the non-fixed section of the support structure. The retaining structure comprises an unloaded side of the non-embedded section and an embedded section; the displacement monitoring system includes displacement sensors for monitoring the top displacement and rotation angle of the retaining structure and a fixed inclinometer for monitoring the horizontal displacement of the retaining structure along its depth, the fixed inclinometer being located inside an inclinometer tube rigidly connected to the retaining structure; the detachable temporary vertical support component is a hydraulic prop or a temporary support structure composed of multiple rigid blocks stacked together; the control and analysis module is a distributed control system consisting of an industrial control computer and a field controller connected via a wireless communication network, the industrial control computer and the field controller having executable programs; the preset safety criteria are used to control the controllable loading support rod to immediately stop loading and gradually unload the test load when the displacement response of the retaining structure reaches a preset allowable value, or the load-displacement response curve of the retaining structure shows an inflection point, or the test load cannot be maintained stably, or the test load reaches a preset limit value; the horizontal bearing design parameters include the horizontal subgrade coefficient distributed along the depth of the embedded section of the retaining structure and the critical load of the retaining structure.

9. The horizontal load testing system for slope retaining structures according to claim 8, characterized in that, The retaining structure located in the non-embedded section of the retaining structure is a sheet pile; the retaining structure located in the embedded section of the retaining structure is wet-sprayed concrete or reinforced mesh wet-sprayed concrete; the retaining structure has an internal cavity structure; the rigid block is a steel block or a precast concrete block; the controllable loading support rod and force transmission rod have: an embedded controller used as the field controller, a self-locking hydraulic jack, a pressure sensor and a load sensor, and an independent power supply, wherein the self-locking hydraulic jack integrates an oil pump, a motor for driving the oil pump, an oil tank, an electro-hydraulic control valve, a hydraulic cylinder, and a hydraulic lock; the field controller in the control and analysis module is connected to the drive unit and force sensor of the controllable loading support rod and the force sensor of the force transmission rod via a wired connection, and the field controller is connected to the displacement sensor of the displacement monitoring system via a wired connection; the control and analysis module is used for: (1) The industrial control computer is used to receive, through the wireless communication network, the displacement response data collected by the displacement sensor of the displacement monitoring system, the load data collected by the controllable loading support rod force sensor and the force transmission rod force sensor, which are summarized and uploaded by the field controller; (2) The industrial computer is used to send control commands to the field controller through the wireless communication network according to the preset loading scheme; (3) The field controller is used to perform closed-loop control according to the received instructions, and drive the controllable loading support rod to perform graded loading and load maintenance; (4) The industrial control computer is used to draw load-displacement curves and determine the critical load of the retaining structure based on the load data collected by the controllable load support rod load sensor at each depth and the displacement response data of the retaining structure obtained by the displacement monitoring system at the corresponding depth. (5) The industrial control computer is used to calculate and output the horizontal subgrade coefficient distributed along the depth of the retaining structure based on the load data collected by the load sensor of the force transmission rod at each depth of the retaining structure and the displacement response data of the retaining structure at the corresponding depth obtained by the displacement monitoring system.

10. The horizontal load testing system for slope retaining structures according to claim 9, characterized in that, The controllable loading support rod and force transmission rod are multifunctional support rods with rollers, hydraulic pins, and self-locking hydraulic jacks. The hydraulic pins are used to lock the rollers. In the locked state, the rollers form rigid contact with the support structure and the retaining structure to transmit loads. The multifunctional support rod is used to load test loads when the self-locking hydraulic jack is in an unlocked state that allows extension and retraction and the rollers are in a free rotation state. The multifunctional support rod is used to transmit test loads when the self-locking hydraulic jack is in a locked state that prevents extension and retraction and the rollers are in a locked state.

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