KR20110121003A - Safety evaluation method for soil shearing work - Google Patents

Abstract

PURPOSE: A method for evaluating safety on a retaining wall work field is provided to perform an accurate evaluation through the correction of a management standard value in which a safety coefficient and a damage weight index are applied. CONSTITUTION: The horizontal displacement data of a retaining wall is collected in a construction field. The horizontal displacement management standard value of the retaining wall is calculated from the horizontal displacement data. The axial force data of a support and the horizontal displacement data of the retaining wall are obtained. A level of collapse risk is calculated from the tendency according to correlation of the horizontal displacement and axial displacement. The index of a collapse weight is calculated from the calculated level of the collapse risk. Through comparing the horizontal displacement data and modified horizontal displacement management value, a collapse risk is calculated.

Description

Safety evaluation method for soil shearing work

The present invention relates to a method for evaluating the collapse safety of the construction site, and more specifically, to prevent collapse accidents that may occur at the construction site in the construction site from the various measuring instruments installed in the construction site walls, ground, various structures, etc. It is about the collapse safety evaluation method that can evaluate the collapse safety of the construction site and accurately predict the signs of collapse from the measurement information obtained after obtaining the information about the site.

In general, the earthquake construction is the most basic work in the construction work, most of the construction work includes the earthquake construction including the ground excavation process. In deciding the underground excavation method for the earthquake construction, the most suitable construction method is selected by considering the ground characteristics, surrounding conditions, expected air, and construction cost for the construction of the structure on the basis of safety and economic feasibility.

As the excavation and clogging method, according to the shape of the excavation surface, it is roughly classified into a slope attachment method and an attachment method using an earth wall. The slope attachment method is a method for excavating a state in which a slope slope can be secured without using an earth wall. The soil wall construction method is applied when it is difficult to apply the slope attachment method. H-pile + soil plate (earth plate), CIP (Cast-In Placed Pile), SCW (Soil Cement Wall), sheet pile, Diaphragm Wall (D / W).

In addition, as a typical soil support method according to the excavation is divided into struts and earth anchors, in addition, there is excavation by the Soil nailing method or raker (raker) support method. Rock bolts are sometimes used instead of earth anchors. In addition, when constructing a continuous wall as an underground continuous wall to support the wall by the slab, it is also possible to apply a top-down to complete the structure from the top to the bottom.

On the other hand, underground structures such as retaining walls, retaining walls, board pile walls, underground hollow spheres are all structures that support the pressure of the original or fill soil. At this time, the pressure of the soil is called earth pressure (meaning the stress generated inside the ground, and all forces generated between the contact between the soil and the structure), and the size or direction of the earth pressure should be determined for the design of the underground structure.

Therefore, the theory of earth pressure has been studied for a long time, and the representative ones are the earth pressure theory of Coulomb and Rankine. Based on this, many earth pressure theories have been studied and presented and used for the design of underground structures and the development of underground spaces.

In earth pressure, active earth pressure (P _a ) is the earth pressure acting when the retaining wall tries to conduct forward by the backfill soil pressure, and passive earth pressure (P _p ) is the earth pressure Earth pressure at rest (P ₀ ) is divided into earth pressure without causing yield to earth block structure and no horizontal displacement.

And, in most ground excavation, although there is a difference in size depending on the size and depth of the ground excavation will necessarily cause the behavior and settlement of the surrounding ground. Ground behavior and settlement are most affected by ground conditions and groundwater changes, but they are also affected by complex types of masonry structure, stiffness, construction method, construction technology level, surrounding topography and conditions.

In the case of settlement that can occur during the construction of the earthquake, it can be settled by the pre-excavation process, by the main excavation, or by the dismantling of the support. In the process of using, the most widely used types of support materials are struts and earth anchors.

In the case of strut jibo, it is necessary to install the intermediate pile for mounting the strut. To install the intermediate pile, drill the auger in advance with an auger, insert the intermediate pile into this hole, and type the pile to the required depth with a vacuum hammer. In addition, the drilling and vibration hammer work affects the adjacent ground, causing settlement. In addition, because heavy heavy equipment is placed on site for the construction, settlement occurs due to the floor load.

If the earth wall type is a continuous wall (D / W, slurry wall), since the exterior wall of the building is installed in advance, a lot of work is required in advance.For accurate trench excavation, a guide wall is installed and the excavation proceeds. In this case, the slurry is put in the excavated place so that the hollow wall is not torn down, the excavation is carried out to the required depth, and after the excavation, the pre-manufactured steel is put and concrete is poured. At this time, although there is a slurry in the hollow wall, displacement inevitably occurs due to the stress relaxation of the adjacent ground due to the excavation, and settlement occurs in the adjacent ground due to the equipment for excavation and slurry replenishment.

When the earth wall is CIP, processes such as perforation, casing insertion, rebar and steel insertion, and concrete placement are required. In each case, considerable vibration and load are generated.

When forming the earth wall with the thumb pile and the earth plate, it is necessary to insert the H-pile (H-pile) in the same way as the installation of the intermediate pile, which causes settlement in the adjacent ground. In addition to the preparation work for the installation of earth walls and supporting materials, there are cases in which work for reinforcing the ground is necessary in advance. Ground reinforcement works are usually performed to increase the stiffness of the earth walls or to increase the rigidity of the earth walls. Accompanying the high pressure, low pressure reinforcement insertion process, the disturbance and settlement of the adjacent ground is made.

Settlement by this excavation is the process that causes the most displacement when considering settlement by excavation, and as the excavation progresses, the soil which acts as a restraint is removed, and the stress of adjacent ground is relaxed and redistributed, so the movement of ground This is caused. In addition, when an anchor is constructed with earth walls or supports with poor water quality when excavation proceeds in the ground state with high groundwater level, inflow of groundwater into the site cannot be avoided, which causes the groundwater level of the adjacent ground to fall. It causes an increase in stress, which causes additional ground subsidence.

In addition, the jibo installed for temporary purposes is generally dismantled while constructing the underground structure in order to build the actual structure or to secure more space, which is not supported until the structure to replace the existing support role is constructed in this process. Since the state is dismantled, the ground displacement due to the support gap is inevitable until the outer wall of the basement or the basement floor slab is installed to replace the disassembled support.

In addition, the dismantling of the jibo, because the position of the actual structure overlaps with the position of the jibo can not be avoided excessive disassembly, which is the case that the position of the jibo to be dismantled interferes with the construction of the actual structure, making it difficult to proceed with construction. Excessive support dismantling in this case results in large ground displacements.

And, after the earthquake is installed during the excavation construction and the support for restraining the movement of the ground is installed, a large displacement is caused at the intermediate position by the arch effect generated when the movement of the ground is restrained. This general earth pressure distribution, that is, static earth pressure, main earth pressure, and manual earth pressure are different from each other, many studies have been conducted.

In addition, there have been studies on the influence factors and analysis of the wall behavior, for example, the behavior of ground and wall walls according to the rigidity of the wall, the behavior of the wall wall according to the preceding load of the struts, and the behavior of the wall wall according to the excavation step by step. Various studies on the phenomenon have been conducted.

In addition, studies have been conducted on the flexural stiffness of the wall, the deformation and strut stiffness of the wall, the temporal delay of the wall, the indentation depth of the wall and the preceding load of the strut.

On the other hand, in the earthquake construction, the earth and sand collapse, because the excavation of the foundation, road, subway, underground, water and sewage, power line, gas pipelines and ground for the construction of the ground, excavates invisible ground, which is difficult to predict change. Many industrial accidents are caused by falling rocks, underground buried materials and falling construction equipment.

In particular, earthquake construction in urban areas can cause many lives and economic losses due to collapse and explosion by water and sewage and gas pipelines. This kind of thinking has become a big social problem.

Underground block construction in the vicinity of a large building requires careful attention and advanced technology from design to construction because a small error in design can cause great human and material damage during construction.

On-site measurement for safety construction in underground masonry construction is the best way to predict hazards in adjacent structures and masonry construction. Although it has been considered insignificant compared to construction, in the present age, all construction work in urban centers is carried out by underground excavation, so measurement must be accompanied.

However, without sufficient knowledge and experience in the measurement can not prevent the damage caused by the error of the instrument or inexperienced use of the user, can lose the trust as a technician and can cause a major accident.

Therefore, in order to effectively detect the collapse of the construction site in advance, it is necessary to clearly understand the characteristics of each construction method of the construction site, and also need a technique for comprehensively analyzing various analysis items by installing a suitable measuring instrument at an optimal location.

Disintegration accidents that occur during excavation at the construction site of the earthquake are characterized by the sudden occurrence of signs of collapse, and even if the signs of collapse are detected, the damage caused by the collapse is more severe because the construction is not stopped and evacuated at the appropriate time. Larger cases are often reported.

As excavation proceeds in the construction of the detachable earthquake, various conditions such as load, external force, and support conditions due to earth pressure, hydraulic pressure, and load loading of adjacent structures in each construction phase affect the stability of the temporary earthquake structure.

In particular, the working earth pressure is redistributed with the displacement of the wall during construction and changes from time to time depending on the construction method and the support state. Attention should be paid to ensuring stability and minimizing the impact on adjacent structures.

In order to prevent accidents due to the construction of the earthquake, it is necessary to conduct a sufficient preliminary investigation of the ground to determine the excavation method and excavation time, and during the work, carry out continuous safety review and safety check by applying a reliable measurement system to eliminate the risk in advance. do. There is also a need to minimize damage through preparation and training in case of accidents.

However, predicting the behavior of structures and foundations and determining the stability are the main tasks to be performed by the technician, but in reality it is not easy to solve the problem satisfactorily. This is due to the scattering of many unknown factors throughout the planning, design and construction process, so that the behavior of the structure and the ground will be different from the design expectations, and in some cases the structure will be destroyed. Can be reached.

Uncertainty in design and construction of structures and grounds is related in detail to uncertainty in terms of strength of materials, members and structures, grounds, uncertainty about loads, irregular changes in external forces, and the weight of soil, and design calculations. Can be distinguished by uncertainty.

In order to overcome such uncertainty, it is necessary to obtain new information through observations during construction to predict future behavior in different ways, or to modify the parameter values used in the initial prediction, to re-predict and to check the safety, and to proceed with construction. . In addition, there is a need for a method for updating the information on the parameter with new information (information construction) to enable construction. This presupposes accurate on-site measurement, and presupposes efficient use of the measurement information and accurate diagnosis using the measurement information.

However, in the field measurement, the techniques related to measurement, such as the purpose of measurement, the type of measurement, the method and method of selecting the instrument, the installation method, the installation location, the quantity, the installation structure, the maintenance and maintenance of the instrument, are well known. However, there is no accurate information on how to use the information obtained from the measuring instrument to obtain accurate safety diagnosis results on the site, and what management should be reflected to reflect the safety diagnosis results.

In particular, it is a level that evaluates the stability of a construction site and predicts collapse by simply comparing the measurement result with the management standard value derived by the technician, and thus it is difficult to obtain accurate predictions and diagnosis results, and thoroughly Difficulties in implementing preventive and effective construction management. It is known that the reliability of actual field technicians is low for the existing management standard value.

In addition, in the management of construction sites based on measurement results, inefficient management through simple experiences of technicians is being carried out. It is true that it is not done properly and always carries the risk of accidents such as collapse.

Therefore, the present invention has been invented to solve the above problems, it is an object of the present invention to provide a method for evaluating the collapse safety of the earthquake construction site that can obtain accurate safety diagnosis results on site by using the information obtained from the measuring instrument.

In particular, the present invention can be carried out without a lot of experience and skilled manpower, accurate stability assessment, high reliability level results in the construction of masonry construction site to enable thorough prevention of safety accidents such as collapse and effective construction management The objective is to provide a method for evaluating collapse safety.

In addition, the aim is to provide a method for evaluating collapse safety that can be used as useful data at various construction sites and to prevent accident risks such as collapse through effective management according to the results of safety diagnosis.

In order to achieve the above object, the present invention,

a) collecting and accumulating the horizontal displacement data of the retaining wall measured by the underground slope meter at another construction site and making a database, and calculating the horizontal displacement management standard value of the retaining wall according to the retaining method from the accumulated horizontal displacement data; ;

b) acquiring the horizontal displacement data of the retaining wall measured by the ground slope system and the axial force data of the support material measured by the axial system at each excavation stage at the construction site to be subjected to the collapse safety evaluation;

c) analyzing a correlation between the horizontal displacement data and the axial force data acquired at the corresponding construction site in real time, and calculating a collapse risk level indicating a collapse risk from a trend according to the correlation between the horizontal displacement and the axial force;

d) estimating the collapse weighting index β from the estimated collapse risk rating;

e) using the collapse weighting index β to modify the horizontal displacement management standard value of the soil barrier method calculated in step a);

f) determining collapse safety by comparing the horizontal displacement data measured in step b) with the modified horizontal displacement management value of step e);

Provides a method for evaluating the collapse safety of the construction site including a.

Accordingly, according to the method for evaluating the collapse safety of the earthquake construction site according to the present invention, it is possible to more accurately evaluate the management standard value by applying the safety factor and the decay weighting index, while more effectively preventing the collapse risk. have.

In addition, by using the information obtained from the instrument, accurate safety diagnosis results can be obtained on-site, accurate safety assessment can be performed without many experiences and highly skilled personnel, and thorough prevention of safety accidents such as collapse by obtaining high reliability results And effective construction management.

In addition, the measured data can be used as useful data in various construction sites, and in particular, effective management according to the results of safety diagnosis can prevent accidents such as collapse in advance.

1 is a schematic diagram showing the configuration of a system for performing a safety assessment according to the present invention.
2 is a diagram showing the relationship between the horizontal displacement and the axial force in the trend 1.
3 is a view showing a shape in which both the horizontal displacement and the axial force increases.
4 is a diagram showing the relationship between the horizontal displacement and the axial force in tendency 2. FIG.
5 is a diagram showing an increase in horizontal displacement but a decrease or constant shape in axial force.
6 is a diagram showing the relationship between the horizontal displacement and the axial force in the trend 3.
7 is a view of a shape in which the horizontal displacement is reduced or constant but the axial force is increased.
8 is a diagram showing the relationship between the horizontal displacement and the axial force in the trend 4.
9 is a diagram in which both horizontal displacement and axial force are reduced or uniform.
10 to 15 are diagrams of various examples shown by dividing the maximum horizontal displacement amount δ _hmax by digging depth H and normalizing them.
16 is a flowchart illustrating a process for evaluating the safety of the construction site using the collapse weighting index based on actual measurement data according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

The present invention relates to a method for evaluating the collapse safety of the construction site, and to evaluate the collapse safety of the construction site from the site measurement information and to accurately predict the signs of collapse collapse safety evaluation method to effectively prevent the collapse of the construction site It is about.

As is well known, ground excavation and earthquake construction in urban areas with high density of buildings and populations have a great impact on the surrounding environment as well as enormous human and economic damage in case of accidents. Therefore, a thorough inspection for each stage of design and construction is required. Should be done.

In particular, an accurate safety assessment of the construction site should be carried out using the measurement information during the construction process.For this purpose, an accurate analysis of the cause of the collapse of the construction site, the setting of measurement items to predict the collapse of the construction site in advance, and the safety of each measurement item The research has been reported by several researchers about the measurement management technique to evaluate the results.

In addition, various measurement management techniques have been proposed by various researchers to evaluate the safety of earthquake construction sites based on the measurement results, and compare and review the pre-set management standard values and measurement results (actual values). There is an absolute value management technique for evaluating and a technique for determining safety against a next stage predicted value and a management standard value predicted by the measurement result of the previous stage.

On the other hand, the present inventors have carefully analyzed the characteristics of the earthquake construction and the measurement system applied to the earthquake construction, and also analyzed the optimum method of using the instrument according to the collapse characteristics. It is appropriate to use the ground inclinometer to measure the horizontal displacement of the retaining wall and the axial system to measure the axial force of the support material (strut, etc.) as the optimum measuring device to detect the collapse in advance. It was confirmed.

In addition, it is necessary to confirm the necessity of correcting and supplementing the existing management standard value, and to analyze the measurement data at home and abroad by the earthquake method in order to correct the management standard value, based on the horizontal displacement of the wall, which is the most reliable item in detecting signs of collapse By statistically analyzing the horizontal displacement measurement data according to the drilling depth, safety can be corrected for the first and second horizontal displacement management standard values corresponding to the significance level L1% and L2% (L1> L2) based on the actual measurement data. Coefficient α was derived.

In addition, the existing management standard value is used to further analyze the correlation between the actual measurement data of the measuring instrument at the construction site of the evaluation target, and the collapse risk is quantified based on the trend of the measured data and applied as a weight to the management standard value. Index β was derived.

In particular, it is possible to further analyze the horizontal displacement (measured by underground slope) and the axial force data (measured by the accelerometer) of the earthquake wall measured at the actual construction site to effectively predict the collapse signs in advance. A study was conducted to investigate the correlation between the horizontal displacement and the axial force.

In addition, the measurement results of horizontal displacement and axial force are divided into four categories, and the decay risk indexes for each measurement trend are classified into four categories. A management technique was derived.

First, Figure 1 is a schematic diagram showing the configuration of a system for performing a safety assessment according to the present invention.

As shown, the collapse safety evaluation system of the masonry construction site, a measurement system including a plurality of measuring instruments 11 installed to measure in real time the state of the site of the masonry construction site, the state of the wall, ground, various structures, etc. (10), a transmission / reception unit 14 for transmitting wirelessly or wired measurement data obtained by the respective measurement units 11, and measurement data of each measurement unit transmitted through the transmission / reception unit 14 in a database ( 21) and a monitoring computer 20 for performing a collapse safety assessment on the construction site based on the measured data.

In the above configuration, the measurement system 10 may be composed of a plurality of measuring instruments for detecting the state of the wall, the measuring instrument that is usually used for the detection of the collapse of the wall, such as underground slope meter, groundwater level meter, floor settler , Strut stress gauge, strut axial force gauge, band stress gauge, pore water pressure gauge, surface water pressure gauge, surface sedimentation system, earth pressure gauge, and so on.

-Underground Gradient: Deformation monitoring of earth wall

-Groundwater Level Monitor: Earth pressure increase environment monitoring by groundwater level rise

-Floor settling system: Monitoring of settlement surface by layer of earth wall

-Strut stress gauge: monitors the stress of supporting material

-Strut Aximeter: External force monitoring transmitted from the retaining wall to the support

-Band stress gauge: monitoring the stress transmitted from the earth wall to the band

-Pore water pressure gauge: Change of effective stress of ground

Surface subsidence: Surface subsidence monitoring

-Earth pressure gauge: Ground pressure monitoring

In addition, the transceiver 14 is a component for transmitting the data measured in real time from the measuring instrument to the monitoring computer 20, may be a normal commercial communication module, for example, a communication module capable of wireless LAN (WLAN) communication Can be.

The monitoring computer 20 converts and receives data received from each measuring instrument through the transmission and reception unit 14 into collected measurement data, and stores the collected measurement data in the database 21 by classifying the applied method. It is a component that performs safety evaluation of construction site in real time using collected measurement data.

Of course, the monitoring computer 20 is provided with its own transmission / reception unit (not shown) for receiving or transmitting measurement data wirelessly or by wire (transmitted to an integrated monitoring server or a monitoring computer at another construction site). The transmission and reception unit of the monitoring computer 20 may be a known commercial communication module, for example, may be a communication module capable of wireless LAN (WLAN) communication.

The monitoring computer 20 processes data such as horizontal displacement and axial force received from the transmission / reception unit 14 into data usable for the collapse safety evaluation, and stores the data in the database 21. Safety assessment through the analysis of trends of horizontal displacement and axial force, calculation of collapse risk level, calculation of collapse weighting index, calculation of management standard value (correction of management standard value) by each method, comparison of measured data and management standard value, risk alarm, etc. do.

In addition, the monitoring computer 20 may be connected to the alarm system 22, in which the alarm system 22 generates a danger alarm by a signal output from the monitoring computer 20 according to the safety evaluation result and outputs the danger alarm. You will be alerted.

In addition, the monitoring computer 20 may be communicatively connected to the integrated monitoring server 30 that receives the measurement data of the other construction site from the monitoring computer 40 of the other construction site, and monitors the measurement data of the construction site. Transmission to the server 30, or receives the measurement data of the other construction site from the integrated monitoring server (30). At this time, the monitoring computer 20 stores the measurement data of the other construction site received from the integrated monitoring server 30 in the database 21 for each construction method.

In addition, the monitoring computer 20 may be directly connected to the monitoring computer 40 of the other construction site, and at this time to receive the measurement data of the other construction site directly to separate the corresponding method and stored in the database 21, The measurement data transmitted from other construction sites is continuously accumulated and utilized in the database 21.

Hereinafter, the collapse safety evaluation process performed in the monitoring computer will be described in detail.

The process of evaluating the collapse safety according to the present invention includes: a) collecting and accumulating the horizontal displacement data of the earthquake wall measured by the ground slope system at another construction site and making a database, and storing the earthquake wall by the earthquake method from the accumulated horizontal displacement data of the earthquake wall. Calculating a horizontal displacement management reference value of the; b) acquiring the horizontal displacement data of the retaining wall measured by the ground slope system and the axial force data of the support material measured by the axial system at each excavation stage at the construction site to be subjected to the collapse safety evaluation; c) analyzing a correlation between the horizontal displacement data and the axial force data acquired at the corresponding construction site in real time, and calculating a collapse risk level indicating a collapse risk from a trend according to the correlation between the horizontal displacement and the axial force; d) calculating a predetermined collapse weighting index from the real-time calculated collapse risk rating; e) using the collapse weighting index β to modify the horizontal displacement management standard value of the soil barrier method calculated in step a); and f) comparing the horizontal displacement data measured in step b) with the modified horizontal displacement management value of step e) to determine the collapse safety.

Here, the horizontal displacement management reference value modified in step e) is obtained by the horizontal displacement management reference value calculated in step a) and the collapse weighting index β calculated in step d).

First, the present inventors have derived through the continued research that the important instruments for evaluating the collapse safety of the construction site of the above-mentioned measuring instrument can be a ground slope and an axial force meter. The underground inclinometer is installed to measure the deformation (horizontal displacement) of the wall, and the axial system is installed to measure the axial force of the support. These instruments are the most effective instruments to directly grasp the behavior of the retaining wall, and it is confirmed that the signs of collapse in the retaining construction site are shown directly by the underground slope and the axial force meter.

In more detail, representative methods applied to the earthquake construction include H-pile + earth plate, CIP, SCW, board pile, underground continuous wall, and slurry wall. In these methods, the earthquake wall is due to the characteristics of the earthquake process. There is a difference in the composition of the struts, that is, struts, or support materials, are used in all construction methods. The support material is an essential member for controlling the deformation of the retaining wall, and thus, the common main members constituting the retaining wall regardless of the retaining method are the retaining wall and the retaining material.

At this time, the ground inclinometer and the axial system are the most basic ground measuring instruments to monitor the destruction of the support materials and the collapse of the retaining wall, and the signs of collapse can be detected by the ground inclinometer and the axial system. The displacement and the resulting increase in external force allow for a more accurate quantitative assessment of the behavior of the structure compared to the strain. In addition, the instrument for measuring the axial force of the ground slope and the support material is relatively accurate than the instrument for measuring the strain, and can reflect the overall behavior of the structure.

Therefore, it is desirable to install the ground slope meter and the load bearing axial system using the load gauge at the construction site. Since the response from each sensor has a close relationship with each other, the measurement results can be analyzed at the same time. Have In addition, the accident at the construction site of the earthquake construction site is caused by the destruction of the support material and the collapse of the retaining wall, and the measuring instruments that can directly monitor the destruction of the support material and the collapse of the retaining wall are the underground inclinometer and the axial system.

Of course, in order to predict the signs of collapse of the construction site in advance, it is most accurate and desirable to perform the integrated analysis by combining all the measurement results of the various measuring instruments described above, but considering the reality of the construction site, various measuring instruments are appropriate for all sites. It is a well-known fact that it cannot be arranged.

The collapse accident at the construction site starts with the collapse of the retaining wall and the support material, which can be measured by the underground inclinometer and the axial force meter, and considering the importance of the measurement, the ground slope, that is, the earthquake, It is desirable to measure the horizontal displacement of the wall and the axial force of the support. In particular, since the collapse accident is necessarily caused by the collapse of the retaining wall, it is reasonable to select the underground slope meter as the most important analysis measurement item.

However, if additional instruments are available, the results can be used as indirect data to analyze the factors that increase ground slope and axial force from the point of view of collapse detection. The strut stress gauge and the band stress gauge can be categorized as the instruments that directly monitor the collapse.However, the vibration strain gauges commonly used to measure stress can vary the measurement results according to various external environmental factors. Because of its relatively low reliability, it is not advisable to use the strain gauge as the main measuring instrument to predict collapse accidents at the construction site, and it is desirable to use it as an auxiliary data when analyzing the measurement results of underground inclinometers and axial meters.

The underground slope system 12 can be installed on the back ground or incision slope of the earth wall 1 as in the usual case, and the axial meter 13 shows the state of change of the support material, that is, the strut axial force according to the stepwise excavation. It is possible to attach a load gauge between the strut 2 and the jack so that the measurement can be made so that the axial force can be measured (see FIG. 3). In the case of using additional measuring instruments in addition to the underground inclinometer 12 and the accelerometer 13, each measuring instrument is installed by selecting the installation method and location in accordance with the general field measurement as in the case of the inclinometer and the accelerometer.

As described above, it is most effective to estimate the collapse of the earthquake construction site by the horizontal displacement of the earthquake wall measured using the ground slope system and the axial force of the strut measured using the axial system. Accordingly, the present inventors analyzed the horizontal displacement and axial force data actually measured at a number of construction sites, and analyzed the actual displacement values of the horizontal displacement and axial force, and confirmed that there is a close correlation between the data of the ground slope system and the axial force system. In other words, the horizontal displacement of the retaining wall appears as an increase in the axial force of the support material supporting it.

However, depending on the site and the ground characteristics, the increase in the horizontal displacement often does not appear as an increase in the axial force of the support. In such unusual cases, the risk of collapse should be carefully assessed by comprehensive analysis of the data from the ground slope and axial force meters in determining signs of collapse at the construction site. Therefore, in the present invention, in order to accurately predict the collapse of the earthen construction site, a method of reassessing the collapse risk according to the data trend of the underground slope system and the axial system is applied.

First, the data trends between horizontal displacement and axial force are divided into four cases as follows. These four data trends are basically based on the fact that the increase in horizontal displacement entails an increase in axial force. It is based on the point at which the trend changes in the pattern of horizontal displacement and increase in output.

Trend 1: When both horizontal displacement and axial force increase

Trend 2: When the horizontal displacement increases but the output decreases or is constant

Trend 3: The horizontal displacement decreases or is constant but the axial force increases

Trend 4: When both horizontal displacement and axial force are reduced or constant

The above four trends will be described in more detail as follows.

Trend 1

FIG. 2 is a diagram illustrating a relationship between horizontal displacement and axial force in Trend 1, and FIG. 3 is a diagram illustrating a shape in which both horizontal displacement and axial force increase. Reference numeral 1 denotes an earth wall, and reference numeral 2 denotes a support member, that is, a strut. Reference numeral 12 denotes an underground inclinometer installed in the ground, and reference numeral 13 denotes an axial system installed in the strut.

Trend 1, which is a case where both the horizontal displacement and the axial force increases, is the case in which the load on the support member 2 supporting the retaining wall increases due to the displacement generated in the retaining wall 1, as shown in FIG. Corresponds to the data correlation between horizontal displacement and axial force. As shown in Figure 3 due to various factors such as rising groundwater level or increase in the load of the back ground, the main earth pressure is increased to act on the retaining wall, the earth retaining wall was not installed at the appropriate time or due to problems in the construction side When the horizontal displacement of the wall occurs due to a decrease in the rigidity, the support material installed at a position close to the horizontal displacement occurrence position bears more load than before the displacement occurs. Therefore, it appears that the data in the axial force meter 13 which measures the load which the support material bears increases. This measurement tendency is a general phenomenon according to the occurrence of horizontal displacement, and can be said to be an index for evaluating the reliability of measurement data. If the horizontal displacement and the axial force are below the management standard due to this tendency, it can be estimated that extremely normal data are being measured. Therefore, in the present invention, when the horizontal displacement and the axial force tend to increase within the management standard value, the risk of collapse of the construction site is set to 2 (II) in the present invention.

Trend 2

4 is a view showing the relationship between the horizontal displacement and the axial force in the trend 2, Figure 5 is a view showing the horizontal displacement increases but the axial force is reduced or constant shape.

Trend 2 is a case where both the horizontal displacement and the axial force increases as shown in FIG. 4, but at one point the horizontal displacement continues to increase until the management reference value, but the axial force decreases or is constant. This tendency 2 occurs due to the phenomenon that the displacement of the retaining wall transitions due to insufficient rigidity or excessive displacement of the retaining wall 1. This arching phenomenon is caused by the structural failure of the retaining wall in the part where the displacement of the retaining wall 1 occurs, and can be judged as a very important sign of collapse. As can be seen in the plan view of FIG. 5, the displacement of the retaining wall 1 can no longer handle the displacement and the displacement is transferred to the surrounding wall. In this case, it may be determined that the scene situation is very dangerous. On the other hand, when analyzing based on the measured data, the axial force may decrease or become constant tendency 2 as the displacement increases at the time when a very small horizontal displacement and axial force are generated according to the excavation process according to the excavation process. Therefore, in order to determine the signs of collapse, not only the data of a simple time point should be analyzed, but also the trend analysis of the measurement data should be carried out in the excavation stage. In other words, if the horizontal displacement and axial force increase to a value similar to the management standard value and the horizontal displacement continues to increase from a certain point, but the axial force decreases or maintains a constant value, there is a trend for a certain period of time. Check the wall deformation shape and support material deformation at the location. Also, even if the displacement and axial force data at the time when this tendency occurs is smaller than the control standard value, the horizontal displacement continues to increase, but if the output decreases or if the constant tendency continues for a certain period of time, the structure inspection, groundwater level and ground subsidence And analyze the data of various measuring instruments such as strain gauges to determine whether to stop construction, reinforcement measures and design changes. As such, the tendency of increasing horizontal displacement and decreasing axial force load due to wall function loss is a dangerous case in which collapse is very likely. Therefore, in the present invention, in case of tendency 2, the risk of collapse of the construction site is evaluated based on the horizontal displacement. The risk level is set to the highest class 1 (Ⅰ).

Trend 3

6 is a diagram showing the relationship between the horizontal displacement and the axial force in the trend 3, Figure 7 is a view of a shape in which the horizontal displacement is reduced or constant but the axial force increases.

As shown in FIG. 6, the horizontal displacement decreases or is constant, but the increase in the axial force is a rare tendency in the actual site. The phenomenon caused by manual earth pressure or ground consolidation between the ground slope system 12 and the soil wall 1 as shown in FIG. It can be evaluated as being. As shown in FIG. 7, the ground slope system 12 is generally installed in the ground within 1m of the earth wall 1 in the vertical direction, and the data obtained from the installed ground slope system 12 is, in principle, of the ground wall of the earth wall. Although it is a variation, the data of the ground slope system 12 in the measurement of the wall construction generally ignores the gap between the wall 1 and the inclinometer 12, and the data of the ground slope system 12 is called the deformation of the barrier wall 1. Will be evaluated. In this case, when the soil condition between the retaining wall (1) and the ground slope system (12) is good and dense, the actual displacement and the displacement of the ground slope system will not change even if the displacement of the retaining wall is evaluated by a general evaluation method that assumes one rigid body. It looks very nice. However, if the ground condition between the retaining wall and the ground slope system is not poor and not dense, the deformation detected in the ground slope system may not be directly connected to the deformation of the retaining wall. In this case, as shown in FIG. 7, in the ground between the retaining wall 1 and the ground slope system 12, a phenomenon in which the deformation of the ground slope system is partially absorbed in the ground occurs, which is the retaining wall 1. While not appearing as a deformation of the support material (2) may appear as a load to bear. Even if this tendency occurs continuously, if it occurs within the horizontal displacement and axial force control ranges, the cause of horizontal displacement reduction is determined by using various instruments such as surface subsidence and groundwater level, rather than being a direct indication of collapse. It is important to carry out general measurement control in comparison with the control values of horizontal displacement and axial force. Therefore, in the present invention, the case of tendency 3 is set to risk class 3 (III) in evaluating the collapse risk of the construction site based on the horizontal displacement.

Trend 4

FIG. 8 is a diagram showing the relationship between the horizontal displacement and the axial force in the trend 4, and FIG. 9 is a diagram in which both the horizontal displacement and the axial force are reduced or uniform.

As shown in FIG. 8, the trend 4 when both the horizontal displacement and the axial force decreases or is constant is to secure the stiffness of the retaining wall 1 according to the increase in the number of installations of the supporting members 2 according to the excavation process, and to reduce the main earth pressure due to the lowering of the groundwater level. It can occur when the factors causing displacement on the retaining wall are reduced due to various causes such as manual earth pressure and increased rigidity due to the reinforcement of the retaining wall. In addition, when the horizontal displacement and the axial force is constant, it can be determined that the retaining wall and the supporting material bear appropriate constant earth pressure and load acting on the retaining wall 1 and the supporting material 2 at that time. On the other hand, when the manual earth pressure is large, as shown in FIG. 9, both the horizontal displacement and the axial force may suddenly decrease, but such cases are not many, and even in this case, the horizontal displacement and the axial force do not exceed the management standard value. Measurement management can be performed in the same manner as all trends 1 increase. In other words, the horizontal displacement and the axial force increase or decrease, or the tendency to return to a constant case, if the horizontal displacement does not turn to a negative value and the axial force does not turn to tension, the earthquake wall and support material are burdened by the increase of earth pressure in terms of measurement management. This is the case that the load is reduced, so it can be evaluated as the case with the least possibility of collapse. Therefore, in the present invention, in the case of the trend 4, the risk of collapse is set to the risk level 4 (IV) class having the lowest possibility of collapse in evaluating the collapse risk of the construction site based on the horizontal displacement.

As described above, according to the present invention, the measurement trend is divided into four types according to the correlation between the horizontal displacement data and the axial force data, the collapse risk level is set for each measurement trend, and then the horizontal level currently acquired at the construction site. By determining whether the correlation between the displacement data and the axial force data corresponds to any one of the four measurement trends, the collapse risk level is calculated.

Of the four measurement trends set out above, trend 2 is the highest risk of decay risk class 1, trend 1 is the decay risk level 2, which is lower than trend 2, and trend 3 is in trend 1. The risk of collapse is set to Grade 3, which has a lower risk of collapse, and Trend 4 is set to Grade 4, which has the lowest risk of collapse.

Table 1 below shows the collapse risk class (Ⅰ ~ Ⅳ) according to the measurement data trend.

On the other hand, the present invention by applying statistical analysis of the actual measurement data of the construction site of the earthquake construction method to apply the current management standard value 1/200, which is uniformly applied by the earthquake method more realistically. Although the control standard is set and managed for each instrument, the underground slope system that can detect the most reliable and most effective signs of collapse among the earthquake construction sites is the trend of measurement data due to the high correlation between the accelerometer and the data. Evaluate together. The four measurement trends of horizontal displacement and axial force are set to four as described above, and the collapse risk classes according to the above are set to four.

In addition, in the case of the trend 2 corresponding to the risk class 1 (Ⅰ) as shown in Table 1, in the present invention, in applying the control standard modified based on the actual measurement data, the more general measurement trend is collapse risk 2 (II). Since it is more likely to collapse than the grade, the weighting index β is introduced to lower the management standard so that the collapse of the retaining wall can be detected in advance. In other words, in case of tendency 2, which has a high risk of decay from the general tendency, the decay risk level is applied as the first level, and a more stable management standard value is applied by applying the preset weighting index β for the first level.

In conclusion, in the present invention, the collapse weighting index β is applied to the management standard value as the concept of safety factor as shown in the following equation (1).

Horizontal Displacement Management Standard × β = Final Collapse Risk Management Standard (1)

Here, the horizontal displacement management reference value (the horizontal displacement management reference value calculated in step a), which is divided into a primary management reference value and a secondary management reference value as described below), is based on the domestic and international measurement data. Statistical analysis as a function of the distribution, the control standard value based on the significance level L1% and L2%, for example, the significance level 5% (primary management baseline) and 1% (secondary management baseline).

In addition, the decay weighting index β is newly introduced in the present invention, after deciding the decay risk level according to the measurement trend derived from the correlation analysis between the horizontal displacement and the axial force, and setting it in advance for the application of the safety factor concept to each decay risk level. If the decay risk level is less than 2, β is 1.0, and if the decay risk level is 1, the value below 1.0 is applied. The final collapse risk management standard value is the final revised management standard value used in the present invention to determine the safety of collapse of the construction site.

In the equation (1), the horizontal displacement management standard value is a management standard value modified for the site construction method through statistical analysis using actual measurement data. By modifying the standard management method, the management standard values are classified by each. In this case, statistical analysis based on a large number of domestic field measurement data is carried out, and the safety factor α (less than 1) based on this is introduced. Using the safety factor α, the trend of measurement data, and the collapse weighting index β according to the risk level, the following equation (2) is obtained.

Original horizontal displacement management standard value 1/200 × α × β = final collapse risk management standard value (2)

The first and second horizontal displacement management reference values reflecting the first and second safety coefficients α by each construction method (0.5 × α because 1/150 = 0.5%), that is, the horizontal displacement management weights in Equation (1) The explanation is as follows.

The present inventors calculated the average and standard deviation of the horizontal wall displacements measured at a large number of domestic brick wall construction sites and assuming that it follows the normal distribution. Calculated. A single-sided test was performed at the 5% and 1% significance level using the t distribution for the population of these normal distributions.The 5% upper limit of the confidence interval was defined as the primary management reference value (= 0.5 × 1st safety factor α) and the confidence interval. The upper limit of 1% of was set as the secondary management reference value (= 0.5 × 1st safety factor α). Here, the primary management reference value is a standard that requires no attention to safety but requires construction, and the second management reference value means a criterion that indicates a dangerous state in excess of the degree of construction of the attention. 10 to 15 are normalized by dividing the maximum horizontal displacement (δ _hmax ) by the digging depth (H) for the results of one-sided test of the control reference value, which is the standard of safety judgment at each construction stage, to a significance level of 5% and 1%. This is an example shown.

The maximum horizontal displacement (δ _hmax ) of the retaining wall was normalized by digging depth (H) and then analyzed as shown in FIGS. 10 to 15, and H-pile + earth plate wall 1 The value of δ _hmax / H, which is the secondary and secondary management reference value, is in the range of 0.31 to 0.41%, and 0.22 to 0.30% in the SCW wall. In addition, the CIP wall shows 0.21 to 0.28%, the slurry month shows 0.23 to 0.36%, and the overall trend is within the range of 0.22 to 0.28%.

Table 2 below shows an example of the management reference value (δ _hmax / H) for the horizontal displacement according to the retaining wall, the primary management reference value is within the range of 0.21 ~ 0.31%, the secondary management reference value is within the range of 0.28 ~ 0.41% You can see that it can be set in.

If the displacement occurs because the normalized value δ _hmax / H of the maximum horizontal displacement exceeds 0.21 ~ 0.31% of the primary management standard, it may affect the structure and adjacent ground, and exceeds 0.28 ~ 0.41% of the secondary management standard. If you do, problems such as ground subsidence, cracks in neighboring roads and buildings appear, so intensive management is required.

The horizontal displacement management standard for each type of retaining wall shown in Table 2 is in the range of 0.21 to 0.41%, which is generally more precise than the control standard applied in the actual site. Disintegration can be detected, and in particular, by applying different management standard values according to the type of retaining wall, the actual phenomenon can be more faithfully reflected than the existing management standard values.

Conventionally, the management standard of the horizontal distance ratio with respect to the vertical distance generally used in actual sites is 1/500 of the primary management standard and 1/200 of the secondary management standard, which is the same percentage as δ _hmax / H. In other words, the 1/500 primary management standard value is 0.2% and the 0.500 second management standard value is 0.5%.

Here, in the case of the conventional absolute value management technique, the measurement result value is compared with the primary management reference value, and if it is less than that, the excavation and field measurement of the next step are performed again, and the measurement result value exceeds the primary management reference value. Construction (increasing the frequency of measurement, strengthening the monitoring system). The next level of excavation and field measurement are carried out in comparison with the 2nd management standard value, but if it exceeds the 2nd management standard value, construction suspension, reinforcement measures, and design changes are carried out.

Table 3 shows an example of setting the decay weighting index, and it can be seen that 0.8, which is a value smaller than 1.0, is applied only when the decay weighting index according to the decay risk level is 1 (Ⅰ). Here, if the collapse weighting index (β) of 0.8 less than 1.0 is multiplied by the control standard value reflected by the safety factor (α), the collapse safety is evaluated through a value corresponding to 80% of the control standard value applied in other trends. As the horizontal displacement increases, the collapse safety can be assessed on a more stable basis for the worst construction conditions where the axial force decreases or remains constant. The decay weighting index β is applied as 1.0 to the decay risk levels 2 to 4 (Ⅱ to Ⅳ), and the management standard for horizontal displacement is a modified management standard value reflecting the safety coefficient α for each construction method (horizontal displacement of equation (1)). The management standard value is applied as it is, and the management standard value reflecting the safety factor is compared with the measured value. In this case, as shown in Equation (2), since the control standard value is modified by the site analysis method through the statistical analysis using the actual measurement data (reflecting the safety factor for each method), it is a value to introduce the collapse safety factor by itself.

In this way, the management standard values for evaluating the safety of the construction site considering the collapse weighting index can be summarized in Table 4 and Table 5 below.

As can be seen from Table 4, the 1/200 horizontal displacement management standard, which was applied uniformly regardless of the earthquake method, was improved to set the management standard values separately for each typical earthquake method. The final management standard is based on the statistical analysis based on a large number of field measurement data in Korea and reflects the safety factor α based on this. In particular, the safety factor α and the collapse weighting index β according to the collapse risk level are additionally reflected. That is, the decay weighting index β according to the decay risk level is additionally reflected in the management standard value reflecting the safety factor α (1/200 = 0.5%, which is 0.5 × α, which is the primary and secondary management standard values in Table 4). Here, the collapse weighting index β is calculated from the collapse risk class based on the measurement trend derived from the correlation analysis between the horizontal displacement and the output.

In the case of Table 4, it corresponds to the collapse risk class 2 to 4, but Table 5 shows the management standard value of the collapse risk class 1 applied to the collapse weighting index of 0.8. In the case of the grade, it can be seen that the management standard value of the horizontal displacement ranges from 0.17 to 0.33% depending on the type of the retaining wall.

As described above, in the present invention, when the measurement trend corresponding to the risk level 1 level is continuously displayed for a predetermined period, the management standard value corresponding to 80% of the modified management standard value reflecting the safety factor is applied by applying the collapse weighting index 0.8, thereby constructing the earthquake construction. It is possible to more accurately reflect the actual phenomena of signs of collapse on site.

On the other hand, the collapse safety evaluation method according to the present invention is to improve the conventional safety evaluation method for evaluating the safety by comparing the measured data with the management reference value based on the absolute value management method, the actual site measurement It is studied in terms of analysis methodology through database of data. Therefore, the safety coefficient α and the decay weighting index β presented in the present invention can be modified and supplemented to a more reasonable value at any time through the continuous database of measurement data. Therefore, the management criteria to which the safety coefficient and the decay weighting index are applied are also changed. It is possible. That is, more accurate collapse safety evaluation criteria can be derived if the measurement data of the construction site including the actual collapse site is continuously accumulated and databased in order to detect and predict the collapse of the construction site more effectively in advance.

15 is a flowchart illustrating a process of calculating the safety coefficient α and the collapse weighting index β for evaluating the collapse safety according to the present invention. As shown, the most reliable horizontal displacement and axial force data for predicting the collapse risk is obtained through the measurement system built on the earthquake construction site, and the horizontal displacement data is arranged according to the excavation depth to analyze the data statistically. Is carried out. Statistical analysis should select an optimal statistical analysis according to the distribution of data and the number of samples.In this case, since a large number of data samples must be carried out on-site measurement at many construction sites, the distribution of t before long-term measurement data is accumulated in a database is accumulated. Calculate the probability density function of and the ratio of the maximum horizontal displacement (δ _hmax ) to the excavation depth corresponding to the significance level of 5% is the primary management reference value, and the maximum horizontal displacement according to the excavation depth corresponding to the significance level of 1% (δ). _hmax ) is set as the secondary management reference value. In this way, the 1st and 2nd management standard values are set for each mud-block method, and from the established 1st and 2nd management standard values, the management standard value of 1/200 (0.5%) and 1, 2, which were applied uniformly regardless of the method, It is possible to derive the first and second safety coefficients α corresponding to the ratios of the secondary management standard values, respectively. In addition, the relevant construction site, which is to be evaluated separately, analyzes the data trends of horizontal displacement and axial force measured by the underground inclinometer and the axial force, and then determines the collapse risk rating. Will be obtained. Subsequently, the first and second management standard values (or the existing management standard value 0.5% × α) and the decay weighting index β are used to re-define the horizontal displacement management standard values for each final mudstone method. The collapse safety is evaluated by comparing it with the horizontal displacement data measured at the construction site. In the present invention, the collapse weighting index β can be applied only to the case of the collapse risk class 1, which tends to increase the horizontal displacement but decreases the axial force or changes to a constant trend.

16 is a flowchart illustrating a process for evaluating the safety of the construction site using the collapse weighting index based on actual measurement data according to the present invention. As shown, the data of the instrument in the field can be obtained in units corresponding to the horizontal displacement and axial force through data conversion and correction, and the measured data is compared with the control reference value to evaluate the collapse safety. Once the primary control baseline is calculated, the measured data is compared with the primary control baseline, and if the measured data do not exceed the primary control baseline, the measurement results are output and the field measurement management is continued according to the next excavation. To perform. However, when the measurement data exceeds the primary management standard value, careful construction is required, and in this case, the measurement frequency is increased, and measurement management is performed with greater attention and precision than the initial measurement. Also, by analyzing the measurement trend of horizontal displacement and axial force continuously, the collapse risk level is calculated. If the grade change occurs, the collapse weighting index α is changed and the appropriate management standard value is modified and applied according to the measurement result. That is, since the measurement tendency may change from the time point at which the primary control reference value and the measurement data are compared to the time point at which the secondary control reference value and the measurement data are compared, the system is constructed to actively reflect the change in the management reference value accordingly.

If the measured data exceed the secondary management threshold, the system should be checked and managed immediately. Since the excess of the second management standard is directly related to the risk of collapse of the construction site, the overall soundness of the measurement system should be evaluated. After it is confirmed that there is no abnormality in the system from which the measurement data has been acquired, a real displacement may have occurred in the structure. Therefore, safety check is performed. Find a room.

In this way, in the present invention, the domestic and international measurement data for each earthquake method is analyzed to complement the maintenance standard, but based on the horizontal displacement of the earthquake wall, which is the most reliable item in detecting signs of collapse, By statistically analyzing the horizontal displacement measurement data, the first and second horizontal displacement management reference values corresponding to the 5% and 1% significance level based on the actual measurement data are corrected.

The primary management standard value and the secondary management standard value can be continuously updated as the horizontal displacement data of the retaining wall continuously collected at other construction sites is accumulated and databased.

In addition, prior to the direct comparison between the modified horizontal displacement management standard value and the actual horizontal displacement measurement result, the correlation between the horizontal displacement measured at the construction site and the axial force is analyzed and the collapse risk level is set according to the trend of the measurement data. The final horizontal displacement management standard is calculated by additionally reflecting the collapse weighting index of the safety factor concept to the revised horizontal displacement management standard according to the collapse risk level.

In addition, the final horizontal displacement management standard value calculated as described above is compared with the horizontal displacement of the earthquake construction site, which is measured in real time, and the collapse safety evaluation is carried out. Follow-up actions such as warning of danger.

In addition, in the case of utilizing the evaluation method of the present invention as described above while continuously using the measurement data of the domestic earthquake construction site as a database, through the real-time reflection of the measurement data and appropriate modification of the management standard value, Accurate collapse prediction and monitoring can be performed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. Modified forms are also included within the scope of the present invention.

1: retaining wall 2: support material (strut)
10 measuring system 11: measuring instrument
12: ground slope system 13: axial meter
14: transceiver 20: monitoring computer
21: Database 22: Alarm System
30: integrated monitoring server

Claims (13)

a) collecting and accumulating the horizontal displacement data of the retaining wall measured by the underground slope meter at another construction site and making a database, and calculating the horizontal displacement management standard value of the retaining wall according to the retaining method from the accumulated horizontal displacement data; ;
b) acquiring the horizontal displacement data of the retaining wall measured by the ground slope system and the axial force data of the support material measured by the axial system at each excavation stage at the construction site to be subjected to the collapse safety evaluation;
c) analyzing a correlation between the horizontal displacement data and the axial force data acquired at the corresponding construction site in real time, and calculating a collapse risk level indicating a collapse risk from a trend according to the correlation between the horizontal displacement and the axial force;
d) estimating the collapse weighting index β from the estimated collapse risk rating;
e) using the collapse weighting index β to modify the horizontal displacement management standard value of the soil barrier method calculated in step a);
f) determining collapse safety by comparing the horizontal displacement data measured in step b) with the modified horizontal displacement management value of step e);
Collapse safety evaluation method of earthquake construction site comprising a.
The method according to claim 1,
The horizontal displacement management reference value modified in the step e) is obtained by the horizontal displacement management reference value calculated in the step a) and the collapse weighting index β calculated in the step d) as shown in the following formula (E1). Method for evaluating the collapse safety at the construction site.
E1: Horizontal displacement management standard of step a) × collapse weighting index β = revised horizontal displacement management standard
The method according to claim 1,
According to the correlation between the horizontal displacement data and the axial force data, the measurement tendency is divided and set as shown in the following A, the collapse risk level is set for each measurement tendency, and the correlation between the horizontal displacement data and the axial force data acquired in step c) A method for evaluating the collapse safety of a masonry construction site comprising determining the collapse risk level by determining that the relationship corresponds to any one of the following measurement trends.
A) Trend 1: When both horizontal displacement and axial force increase
Trend 2: When the horizontal displacement increases but the output decreases or is constant
Trend 3: The horizontal displacement decreases or is constant but the axial force increases
Trend 4: When both horizontal displacement and axial force are reduced or constant
The method according to claim 3,
Of the measured trends of A, trend 2 is the highest risk of collapse risk class 1, trend 1 is the collapse risk class 2, which has a lower risk of collapse than trend 2, and trend 3 is the risk of collapse compared to trend 1. Low Collapse Hazard Level 3, Trend 4 sets the Collapse Risk Level 4 with the lowest risk of collapse.
The method according to claim 3 or 4,
After deciding the decay weighting index in accordance with each measurement trend and decay risk class, calculate the decay weighting index corresponding to the decay risk rating calculated in step d). Disintegration safety evaluation method of earthquake construction site characterized by setting to less than one.
The method according to claim 5,
In the case of the decay risk level of the trend 2, the decay weighting index is set to 0.8, characterized in that the construction site safety evaluation of decay.
The method according to claim 3 or 4,
After setting the decay weighting index in advance according to each measurement trend and decay risk class, calculate the decay weighting index corresponding to the decay risk rating calculated in step d), and the decay risk level of trend 1, trend 3, and trend 4. In the case of the decay weighting index, the decay safety evaluation method of the construction site, characterized in that set to 1.
The method according to claim 1,
The horizontal displacement management standard of step a) is characterized by calculating the primary and secondary management standard values for each mud method by statistically analyzing the horizontal displacement data of the mud wall collected by dividing method in other construction sites. Method of evaluating the decay safety of the construction site.
The method according to claim 8,
The level of horizontal displacement management in step a) is the significance level of L1% and L2% (here, L1> L2) for the population of the normal distribution with respect to the horizontal displacement data of the retaining wall collected by dividing method in other construction sites. One-sided test is performed, but the maximum horizontal displacement (δ _hmax ) is normalized by digging depth (H) for the one-sided test, and the ratio of the maximum horizontal displacement according to the excavation depth corresponding to the upper limit of the significance level L1% is determined. A method of evaluating the collapse safety of a construction site of a brick wall, characterized by setting the ratio of the maximum horizontal displacement according to the excavation depth corresponding to the upper limit of the significance level L2% as the primary management reference value.
The method according to claim 8,
The horizontal displacement management standard of step a) is statistically analyzed by analyzing the horizontal displacement data of the retaining wall collected by dividing method at other construction sites, and the first corresponding to the following equations (E2) and (E3) A method for evaluating the collapse safety of a masonry construction site characterized by calculating the management standard value and the secondary management standard value.
-E2: Horizontal displacement management standard value 1/200 (= 0.5%) x 1st safety factor (value less than 1) = 1st management standard value
-E3: Horizontal displacement control standard value 1/200 (= 0.5%) x 2nd safety factor (value less than 1) = 2nd management standard value
The method according to claim 8 or 9,
The first management standard value and the second management standard value is continuously updated in accordance with the accumulation and database of the horizontal displacement data of the retaining wall continuously collected at other construction sites, characterized in that the collapse safety site evaluation method.
The method according to claim 8,
In the step a), the first horizontal control standard value and the second management standard value are calculated by dividing the primary management standard value and the second management standard value into the first management reference value and the second management reference value by calculating the primary management reference value and the secondary management reference value. A method for evaluating the collapse safety of an earthquake construction site, characterized in that.
The method of claim 12,
In the step f), if the measured horizontal displacement data of the construction site exceeds the primary management standard value, the caution construction is performed to increase the measurement frequency, and if the secondary management value is exceeded, an alarm system at the construction site is exceeded. A method for evaluating the collapse safety of a masonry construction site, characterized by determining whether to stop construction, reinforcement measures, and design changes after alarming of a collapse risk situation.

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