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Latest progress and development direction of foundation pile dynamic test technology
Release time: 2018-06-23

"" Han   bright


100062 (Europe and America Dadi Instrument and Equipment Co., Ltd., Beijing 100062 )


””” 本文概括了高应变法、低应变法和声波透射法等基桩动测技术在近年来的最新进展,归纳了各方法中存在的显著问题以及指出今后基桩动测技术的发展方向。Abstract : This article summarizes the latest developments in the dynamic testing technology of foundation piles such as high strain method, low strain method and acoustic transmission method in recent years, summarizes the significant problems existing in each method and points out the future of dynamic testing technology of foundation piles. Direction of development. "

Keywords: high strain method, low strain method, acoustic transmission method, dynamic measurement of foundation piles

The latest developments and future research of pile dynamic testing technology

Han Liang

(Earth Products China Limited, Beijing 100062)

The latest progress of pile foundation dynamic testing technology in recent years, such as high strain method, low strain integrity method and cross-hole ultrasonic wave method, etc., were summarized in this paper; some significant issues in various method above were also discussed to hope for future deep study of pile dynamic testing. Abstract: The latest progress of pile foundation dynamic testing technology in recent years, such as high strain method, low strain integrity method and cross-hole ultrasonic wave method, etc., were summarized in this paper; some significant issues in various method above were also discussed to hope for future deep study of pile dynamic testing.

low strain integrity method; high strain method; cross-hole ultrasonic wave method; foundation pile; dynamic testing technology Key words: low strain integrity method; high strain method; cross-hole ultrasonic wave method; foundation pile; dynamic testing technology

 

前言 1 Preface


Foundation pile dynamic measurement technology is a multi-disciplinary and complex interdisciplinary. Because the test object is a pile foundation with hidden engineering properties, many influencing factors, and high uncertainty in construction quality, practitioners need to have comprehensive knowledge in pile foundation engineering, rock and soil mechanics, wave dynamics, vibration theory, and dynamic signal processing.

The widespread application of modern foundation pile dynamic measurement technology is undoubtedly closely related to the development of electronic computers. 1932 年以前科学家 St.Venant DVIsaacs ENFox 等人就明确指出打桩作用是应力波在桩身内的传播过程,并将桩周土体阻力参数引入到经典的一维波动方程中求解 [1] As early as 1932 , scientists St. Venant , DVIsaacs , ENFox, etc. clearly pointed out that the piling action is the propagation of stress waves in the pile body, and introduced the resistance parameters of the soil around the pile into the classic one-dimensional wave equation to solve [1 ] . 60 年代, EALSmith 借助计算机采用差分法求解波动方程,获到解析解,解决了应力波理论在打桩过程中的桩土性状。 Until the 1960s , EALSmith used the computer to solve the wave equation by using the difference method, and obtained an analytical solution, which solved the pile-soil behavior of the stress wave theory during the piling process. Smith 法或波动方程分析法 [2] ,用于计算桩身应力、单桩竖向承载力和可打性分析。 This is called the Smith method or wave equation analysis method [2] , which is used to calculate the pile body stress, vertical bearing capacity of single pile, and scorability analysis. 年美国 CASE 西储大学的 Goble GG 教授领导的科研小组受联邦公路局委托,开发了一种实用的监控打桩过程的全新方法。 In 1964 , a research team led by Professor Goble GG of Case Western Reserve University in the United States was commissioned by the Federal Highway Administration to develop a practical new method for monitoring the piling process. It is to collect the dynamic response such as the force and acceleration of a section near the top of the pile, and then use the closed solution of the one-dimensional wave equation to calculate the actual static bearing capacity of the pile under a series of assumptions. CASE 法,它将现场量测技术与波动方程求解有机地结合起来。 This is the famous CASE method, which combines on-site measurement technology with wave equation solving. 70 年代 Goble 等人创立了桩基动力学公司(简称 PDI 公司)以后,在政府的资助下和借助计算机技术迅猛发展,开发了动力试验仪器以及以实测桩顶力和速度为边界条件的曲线拟合数值解法 CAPWAP 程序,不但可以获得桩承载力,而且可以获得土阻力沿桩身分布和模拟静载试验曲线 [3] The foundation pile dynamic measurement technology is really put into engineering application. After Goble and others founded the pile foundation dynamics company ( PDI company for short ) in the 1970s , with the help of government funding and the rapid development of computer technology, they developed dynamic test instruments and The curve fitting numerical solution CAPWAP program with the measured pile top force and speed as the boundary conditions can not only obtain the pile bearing capacity, but also obtain the distribution of soil resistance along the pile body and the simulated static load test curve [3] . TNO )也先后推出了以反射波法为理论基础的基桩低应变测试仪和波动方程拟合计算程序 TNOWAVE The Netherlands Institute of Applied Science Building Materials and Structures ( TNO for short ) has also launched a low-strain tester for foundation piles based on the reflected wave method and a wave equation fitting calculation program TNOWAVE .

China has introduced foundation pile dynamic measurement technology since the 1970s and 1980s. PDA 和桩身完整性测试仪 PIT ,开创了我国基桩动测技术的应用。 At first, only a small number of large scientific research units with abundant funds purchased the piling analysis instrument PDA and the pile integrity tester PIT , which created the application of the dynamic testing technology for foundation piles in China. 年代末期我国的一些科研院所和仪器生产商也着手开展了基桩动测软硬件的研制。 In the late 1980s , some scientific research institutes and instrument manufacturers in China also started the development of software and hardware for dynamic measurement of foundation piles. 1994 年我国颁布了桩基领域的第一本规范《建筑桩基技术规范》( JGJ 94-94 )以及随后出台了《基桩低应变动力检测规程》( JGJ/T 93-95 )和《基桩高应变动力检测规程》( JGJ 106-97 )。 Until 1994 , China promulgated the first specification of the pile foundation field, "Technical Specifications for Building Pile Foundations" ( JGJ 94-94 ), and subsequently issued the "Code for Low Strain Dynamic Testing of Foundation Piles" ( JGJ / T 93-95 ) and " High Strain Dynamic Testing Regulations for Foundation Piles "( JGJ 106-97 ). This period is the most active era for the application and discussion of pile foundation dynamic measurement technology in China. - 初速法、水电效应法、球贯法等。 Various dynamic test methods are constantly emerging, such as reflected wave method, mechanical impedance method (transient, steady state), frequency - muzzle velocity method, hydroelectric effect method, and ball penetration method. 2000 年前后,经过大量工程实践和激烈讨论,以反射波法为理论基础的高应变法 [4] 、低应变法以及声波透射法得到工程界的普遍接受,并纷纷进入各个省部级规范。 Around 2000 , after a lot of engineering practice and intense discussion, the high strain method [4] , low strain method, and acoustic transmission method based on the reflected wave method were widely accepted by the engineering community, and they have entered various provincial and ministerial standards. .

    In recent years, with the advancement of theoretical research, engineering practice, and modern communication technology, some new theories, new methods, and new instruments have been continuously introduced, which has also led to the development of the dynamic measurement of foundation piles. The following is a brief description of new technologies emerging in recent years.

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技术进展 2 technical progress


高应变法 2.1 High strain method

以求解一维波动方程为基础的扩展非线性土模型 2.1.1 Extended nonlinear soil model based on solving one-dimensional wave equation

辐射阻尼模型 a. Radiation damping model

模型只考虑了桩的运动来计算土阻力,即土体处于刚性支撑作用。 The Smith model only considers the movement of the pile to calculate the soil resistance, that is, the soil is under a rigid support. When the soil resistance is increased, such as a pile with a rough surface on the side of the pile is placed in non-cohesive soil or a rock-socketed pile, the movement of the pile becomes smaller, and the movement of the soil increases. At this time, the stress wave energy is radiated from the pile to the inside of the soil instead of being consumed by the shearing action of the soil. 2L /C 前侧摩阻力高而 2L /C 后总阻力低,且 Smith 阻尼系数超过 1.3 s/m The measured curve shows that the first 2L / C friction is high on the front side and the total resistance after 2L / C is low, and the Smith damping coefficient exceeds 1.3 s / m . In this regard, a radiation damping model is introduced. The mass of the soil participating in the movement (called the supporting mass) and the motion variable of the soil (called the radiation damping coefficient) are used to consider the case where the slip surface is not on the side surface of the pile.

桩身裂隙模型 b. Pile body crack model

The pile model may include a tension or fracture model to simulate a pile or crack. If the crack is opened, the compression wave will be totally reflected; if the crack is closed, the compression wave will be transmitted. When the crack is fully opened, a tensile wave will propagate. This model can not only simulate fully open cracks, but also simulate partial cracks. For example, if there is a steel bar connection in the pile body that is not fully opened or the cracks occupy only a part of the cross-sectional area, a part of the force wave is allowed to pass through the cracks or the pile-joining site. .

广义土塞模型 c. Generalized soil plug model

The traditional theory called the phenomenon of soil pouring into piles (concrete pipe piles, steel pipe piles) during the sinking process into the soil plug effect. The interaction between the soil plug and the inner wall of the pile pipe is very complicated, and it has a great influence on the sinking behavior and bearing capacity of the end opening driving pile. The soil plug has two effects: incomplete occlusion and complete occlusion. For large-diameter piles, the height of the soil plug is generally less than the depth of penetration into the soil layer, and the possibility of a complete occlusion effect of the soil plug is relatively small. In recent years, there has been a new perspective on soil plugging, which is to consider soil plugging as an additional mass of soil that pours into the pile body around the pile or sticks to the outside of the pile, forming inertial forces and the pile during the pile driving process. Moving together is called broad soil plug. The function of soil plug will make the soil resistance lag behind.

残余应力模型 [5] d. Residual stress model [5]

Smith 模型。 In the conventional wave equation analysis, an ideal Smith model is used for the pile-soil element . The number of hammers is calculated by subtracting the average spring limit from the maximum displacement of the soil at the end of the pile. When the soil resistance on the side of the pile is small and the strength of the pile body is high, the elastic limit of the required elastic compression soil is small, and the calculation of the number of hammers is basically correct. However, with the lengthening of the pile body, a lot of soil layers need to be traversed during the sinking process. The soil resistance at the side of the pile and the soil resistance at the end of the pile constantly change, that is, the elastic limit of the soil changes greatly, and the error in calculating the number of hammers is very large. The residual stress calculation method is introduced into the wave equation analysis of foundation piles, which greatly improves the accuracy of calculating the number of hammers. The basic concept of residual stress analysis is to find out the displacement and static soil resistance when the pile is completely in a static state, that is, when the system reaches a state of static equilibrium. That is, when the soil element on the side of the pile moves upward, its soil resistance first decreases to zero and then becomes negative, until the balance of the upward soil resistance on the lower part of the pile body and the downward soil resistance on the pile side is balanced, the pile is at rest and the compression force That is, the residual stress is preserved in the pile and soil.

以无线数据传输技术为特色的最新基桩试验仪器 2.1.2 The latest foundation pile test instrument featuring wireless data transmission technology

数据采集 a. Data collection

动测是评价基桩承载力的最先进技术,近年来 借助现代手机和 INTERNET 远程通讯技术,试验人员坐在办公室如同亲临现场一样实时采集、分析数据及与现场人员保持联络,而无需携带大量电缆,简化了现场布置。 PDA dynamic measurement is the most advanced technology for evaluating the bearing capacity of foundation piles. In recent years, with the help of modern mobile phones and Internet remote communication technology, testers can sit in the office and collect and analyze data in real time as well as stay in touch with field personnel without having to carry a large number of Cables simplify field layout. The sensor uses an intelligent stress ring and accelerometer with wireless data transmission capabilities. For the piling monitoring test, damage to the cables and sensors during hoisting is avoided, and the safety of operation is greatly improved.

曲线拟合程序 b. curve fitting program

CAPWAP 是被广泛接受且唯一被规范认可的能够与静载试验结果相比拟的软件。 The curve fitting program CAPWAP is widely accepted and the only software that can be compared with the static load test results. CAPWAP 分析计算,至少需要数天时间才能提供最终报告。 For decades, engineers with rich professional knowledge need to collect data on site and then return to the office for CAPWAP analysis and calculation. It will take at least several days to provide the final report. iCAP 技术正彻底变革这个过程。 The recent emergence of iCAP technology is revolutionizing this process.即时信号拟合技术可在没有任何人工干预的情况下从实测曲线中提取土体运动信息并计算试验时刻的承载力和生成模拟的静载试验曲线,所有这些都是随着试验过程实时获得。 ICAPreal-time signal fitting technology can extract soil movement information from the measured curve without any manual intervention, calculate the bearing capacity at the test moment and generate a simulated static load test curve, all of which follow the test process Get it in real time.提供可 靠的即时的承载力结果。 ”” ” ICAPprovides reliable and immediate carrying capacity results. iCAP 可满足研究人员对唯一解的要求、工程对快速提供结果的要求以及满足规范的要求。 The fully automatic iCAP can meet the requirements of researchers for unique solutions, the requirements of engineering for fast results, and the requirements of specifications.

依托专家系统库的土参数优化收敛功能 c. Relying on the soil parameter optimization and convergence function based on the expert system library

CAPWAP 软件中提供了大量了自动优化功能,可以对桩侧土和桩端土土阻力以及土模型参数(阻尼、弹限等)进行快速优化,这得益于软件中集成了专家系统,大大提高了分析的准确度和效率。 The latest CAPWAP software provides a large number of automatic optimization functions, which can quickly optimize the soil resistance at the side of the pile and the soil at the end of the pile, as well as the soil model parameters (damping, spring limit, etc.), thanks to the integration of an expert system in the software. Greatly improved the accuracy and efficiency of the analysis.

快速荷载法试验 2.1.3 Fast load method test

200ms 时间内始终处于压应力,状体受到的压力与静载试验十分接近,这种方法称为快速荷载法试验。 On the basis of the conventional high strain method test, the weight of the hammer and the special hammer pad are increased, so that the wave phenomenon in the pile body can be ignored. Under the test state, the soil around the pile is always under compressive stress for up to 200ms . The pressure is very close to the static load test. This method is called the fast load method test. ASTM 标准和日本岩土规范。 In recent years, this method has entered the American ASTM standard and the Japanese geotechnical code. [6] 记录桩顶在荷载作用下的运动过程,结合多循环试验卸载点法分析,现场获得充分激发的土阻力信息,进而推定单桩竖向极限承载力。 Compared with the traditional method, the high-speed camera [6] records the movement process of the pile top under the load, combined with the multi-cycle test unloading point method analysis, obtains the fully excited soil resistance information on the site, and then estimates the vertical ultimate bearing capacity of the single pile .

在整体锤上安装加速度传感器测量桩顶锤击力 2.1.4 Install an acceleration sensor on the overall hammer to measure the hammer force at the top of the pile

1.5 倍桩径的安装要求,以克服浅部复杂应力波干扰对测试信号的影响。 Considering the high strain test of cast-in-place piles, it is often necessary to make a longer pile cap or excavate a section of the pile body, so that the force sensor meets the installation requirements of 1.5 times the pile diameter to overcome the impact of complex stress wave interference on the test signal in the shallow part. . In recent years, some engineers at home and abroad have proposed installing an acceleration sensor into a free-fall hammer to measure the hammer force at the top of the pile without installing a force sensor. However, there are still many controversies in this method, such as the fact that the measured hammering force cannot directly indicate the response force containing soil resistance information, the measured speed and the measured hammering force are not on the same section.

低应变法 2.2 Low strain method

以应力波反射法为基础的针对特殊应用而开发的新技术 2.2.1 New technology developed for special applications based on the stress wave reflection method

双速度测试 [7] a. Double speed test [7]

For foundation piles under existing foundations, testing the integrity of the pile body is a recognized problem. The use of dual-speed testing and analysis technology provides a new idea for solving the integrity of the foundation piles, the average wave velocity, and the extraction of upward waves under the existing foundation. 沿桩侧安装两个加速度传感器,同时采集两个加速度曲线,通过公式计算可以确定两个传感器间桩身平均速度以及从实测波形中分离出上行应力波,进而判断桩身完整性。 The dual speed test is to install two acceleration sensors along the side of the pile and collect two acceleration curves at the same time. The formula can be used to determine the average speed of the pile body between the two sensors and isolate the upward stress wave from the measured waveform to determine the integrity of the pile body. . However, the existing foundation forms are different, the mining and industrial conditions are very complicated, the selection of the impact point is difficult, and the quality of the measured curve is greatly affected, especially the sensors below are more susceptible to interference by various factors; the sensor distance, calibration coefficient, and sampling frequency Etc. will also affect test accuracy.

侧剖面分析 [8] b. Side profile analysis [8]

相对于桩顶截面进行归一化处理 获得整个桩身截面变化,进而可以获得实际的灌注体积。 In order to quantitatively explain the measured low strain curve, the effects of the incident wave and the soil resistance wave in the measured speed curve are removed, and only the stress wave derived from the change in the impedance of the pile body is left. The normalization process obtains the change of the whole pile cross-section, and then the actual pouring volume can be obtained. This method considers not only the amplitude of the velocity, but also the duration of the reflection. It requires that the reflection at the bottom of the pile is clear and that the main reflection should be attributed to changes in the section of the pile body or changes in the material properties. 用于中短桩长的低应变法速度反射曲线的近 似量化,而对于长桩或处于高阻力土层中的桩以及无可靠桩底反射的桩无意义。 This method can only be used for the approximate quantification of the low-strain method velocity reflection curve for short-to-medium pile lengths , and it is not meaningful for long piles or piles in high-resistance soil layers and piles without reliable pile bottom reflections.

以扭转波维理论基础的低应变测试法 2.2.2 Low strain test method based on torsional wave dimension theory

An impact torque is applied to the pile top to obtain the transient torsional dynamic response of the pile top. [7] 等人研究了层状土中多缺陷桩在桩顶冲击扭矩作用下桩顶扭转响应解。 Liu Dongjia [7] et al. Studied the torsional response of multi-defective piles in layered soil under pile top impact torque. The pile-soil interaction is considered. Laplace 变换和传递矩阵,解满足初始条件和边界条件的一组偏微分方程,导出桩土系统的传递函数,得到桩顶某点扭转振动速度的频率响应函数和频率域表达式。 The Laplace transform and transfer matrix are used to solve a set of partial differential equations that satisfy the initial and boundary conditions. The transfer function of the pile-soil system is derived, and the frequency response function and frequency domain expression of the torsional vibration velocity at the point of the pile are obtained. Fourier 逆变换计算。 The time history of torsional vibration velocity at this point is calculated by the fast Fourier inverse transform. Low-strain test piles using torsional waves are suitable for short piles with soft soil around the pile or for testing of shallow defects. Because torsional waves have theoretical advantages over P-waves for reflection identification of various defects, torsion-wave tests can be used as an important auxiliary method for P-wave tests, which is of great significance for improving the reliability of low-strain dynamic data interpretation.

以无线数据传输方式的最新测试仪器 2.2.3 The latest test instruments by wireless data transmission

Technological advancements in the electronics industry have made low-strain instruments more and more miniaturized, and wireless transmission technology has eliminated the need for a cable connection between the sensor and the host. 型的低应变测试仪 PIT-X 问世,它的主机可放在手掌中,使用一个无线加速度传感器采集数据。 The newest low-strain tester PIT-X has come out this year . Its host can be placed in the palm of your hand and use a wireless acceleration sensor to collect data. This also marks a new era for low-strain test instruments.

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声波透射法 2.3 Acoustic Transmission Method

相对能量法 [9] a. Relative energy method [9]

In China, the amplitude index is used to reflect the measured signal strength. Due to noise interference and other factors, it is difficult to accurately pick up the amplitude. The relative energy method calculates the voltage of the peak value of the measured signal during the specified period along the time axis. Not only the amplitude of the first wave but also the amplitude of several points after the first wave are used to make fuller use of the actual measurement. The signal can more effectively and effectively reflect the signal strength.

层析成像技术 b. Tomography

Tomographic imaging technology is used to carry out mathematical calculations on the data of limited actual cross-sections to establish two-dimensional and three-dimensional images, which can quantitatively determine the shape, position and size of defects. Tomography can be divided into ray tomography and wave equation tomography. Wave equation tomography has a series of difficult problems such as extraction of scattered data, elimination of various interference factors (sound source signal, medium absorption, transducer coupling) and so on, but it is difficult to be practical. At present, the main application is ray tomography, which assumes that ultrasound waves are propagated by rays and uses the first arrival time of the first wave to perform inversion approximations. ASTM 标准,希望将该技术纳入大直径 灌注桩桩身质量检测中,以补充当前只使用 XY 图作为判缺标准。 The United States has compiled practical 3D imaging analysis software and recommended it to the ASTM standard, hoping to incorporate this technology into the quality inspection of large-diameter cast-in-place piles to supplement the current use of only XY maps as the criterion for determining defects. This will be one of the development directions of the acoustic transmission method in the future.

多通道测试技术 c. Multi-channel test technology

3 管或 4 管混凝土桩的全组合测试。 The multi-channel self-receiving and self-receiving function realizes the complete combination test of pre-buried 3 or 4 pipe concrete piles in one lift . Significantly improve the detection efficiency, greatly reducing the work intensity of the field inspection staff.

发展方向 3 development direction

    Although the dynamic testing technology of foundation piles has developed rapidly in recent years, in fact, this technology has not been widely used for only two or thirty years. It is only a matter of the past ten years in China. From basic theory to application experience, it needs to be further accumulated and improved. . At present, there are still many practical problems that cannot be solved, which brings challenges to the application of foundation pile dynamic measurement technology, which is also the future research and development direction of foundation pile dynamic measurement technology.



3. Development direction


动力荷载作用下桩土受力性状和破坏模式与静载作用的关系 3.1 The relationship between the behavior of piles and soil under static load and the failure mode and the effect of static load

When the dynamic load is applied, the stress and failure modes of the pile-soil system are different from the static load. How to meet or approach the pile-soil behavior during the static load test must consider the effects of dynamic resistance and elastic limit in dynamic measurement. . Smith 阻尼,然而 Smith 阻尼系数实际代表的不仅是桩土界面上的粘滞阻尼,而且还间接代表了由于土体惯性、辐射阻尼等因素产生的能量损失。 In the high strain method fitting, Smith damping is mainly used . However, the Smith damping coefficient actually represents not only the viscous damping at the pile-soil interface, but also indirectly represents the energy loss due to soil inertia and radiation damping. To fully stimulate the soil resistance requires that each soil element exceed its corresponding elastic limit, and the soil elastic limit for pile sides and pile ends with different properties still depends on experience. Qs 曲线呈现缓变型的大直径灌注桩或扩底桩来讲,桩端土阻力充分发挥需要很大的弹限,很难使用现有的数理模型进行模拟。 For large-diameter cast-in-situ piles or bottom-expanded piles where the Qs curve of the static load test is slowly changing, full play of the soil resistance at the end of the pile requires a large elastic limit, which is difficult to simulate using existing mathematical models.

应力波脉冲输入和反射的控制和提取 3.2 Control and extraction of stress wave pulse input and reflection

For the low-strain method test, controlling the energy of the stress wave in the input pile body so that defect reflection and pile bottom reflection can be controlled and optimally matched in energy, which is the first step to successfully determine the integrity. For different pile types, soil conditions around piles, and defect properties, the use of targeted and controllable input energy is still lacking research. Among the obtained measured speed curves, extracting the impedance change information of the traveling wave propagating in the pile body is the key to the analysis and calculation technology. Various software currently in use have limited data processing and ability to extract effective information. The above-mentioned problems are mainly reflected in the quality of multi-section driven piles, the multi-section changes of cast-in-place piles (such as branch-and-pile piles, underreamed piles, and artificially-drilled piles), shallow defects, gradual defects, or multiple defect identification, as well as There are aspects such as the integrity of the foundation pile or inclined pile under the foundation.

完整性判别的定量化技术也是今后的发展方向 3.3 Quantitative technology for integrity discrimination is also the future development direction

The in-depth study of the influence of soil resistance on the velocity of the stress wave, the attenuation characteristics of the stress wave in the pile body, and the variation of the traveling wave with multiple impedance changes is the key to quantifying the average wave velocity, the location of the defect, and the size of the defect. Acoustic transmission testing also requires further research on defect quantification; on the basis of existing tomography techniques, a better inversion algorithm is sought to improve the accuracy of defect quantification.


结论 4 Conclusion


50 多个国家普遍应用。 Foundation pile dynamic measurement technology is currently widely used in more than 50 countries around the world . 500 万根。 According to incomplete statistics, in recent years China has used a large amount of piles more than 5 million. The dynamic testing technology of foundation piles has great potential in the design phase of foundation piles, in the construction monitoring phase, and in the stage of pile acceptance inspection. The low-strain method based on the theory of wave and vibration can be used to test the integrity of the pile body of the driving pile and the cast-in-place pile; the acoustic transmission method based on the ultrasonic transmission theory can deeply test the integrity of the pile body inside the concrete; The high strain based on the equation can determine the vertical bearing capacity of a single pile.

Due to the complexity of soil changes and the defects of the pile body, the dynamic measurement technology of foundation piles needs to be continuously researched and improved from theory to practice, and it is far from mature. This can be seen as a challenge to the dynamic measurement technology of foundation piles, or as an opportunity for the development of dynamic measurement technology for foundation piles.

 

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[2] Wave Equation Correlation Studies. STRESSWAVE "96 Conference, Thendean, G., Rausche, F., Svinkin, M., Likins, GE, Wave Equation Correlation Studies. STRESSWAVE "96 Conference, September, 1996, page 447-464

[3] Recent WEAP Developments. Third International Conference on the Application of Stress-Wave Theory to Piles, Rausche, F., Goble, GG, Likins, GE, Recent WEAP Developments. Third International Conference on the Application of Stress-Wave Theory to Piles, May 1988

韩亮 . 打桩监控试验理论及其应用 [J]. 天津建设科技 ,1998 [4] Han Liang . Pile driving monitoring test theory and its application [J]. Tianjin Jianshe Science and Technology , 1998

韩亮译 . GRLWEAP 波动方程分析程序 [M] . 欧美大地仪器设备中国有限公司 ,2005 [5] Translated by Han Liang . GRLWEAP Wave Equation Analysis Program [M] . Europe and the United States Geodetic Equipment China Co. , Ltd. , 2005

[6] A case study on bridge health check using position sensitive detector technology,2007 Takaaki Miyasaka, A case study on bridge health check using position sensitive detector technology, 2007

韩亮 . 既有基础下基桩完整性测试双速度分析方法 [J]. 建筑科技 ,2007 [7] Han Liang . Two-speed analysis method for foundation pile integrity test under existing foundation [J]. Architecture Technology , 2007

刘东甲 . 扭转波应用于低应变动力测桩的理论研究 [J ]. 岩土工程学报 ,2003 [8] Liu Dongjia . Theoretical study of torsional wave applied to low strain dynamic pile testing [J ]. Chinese Journal of Geotechnical Engineering , 2003

韩亮 . 桥梁灌注桩声波透射法检测新技术及其应用 . 铁道建设 [J],2006 [9] Han Liang . New technology and application of acoustic transmission method for bridge cast-in-situ piles . Railway construction [J], 2006

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