CN104880366A - Soil body kinetic parameter and anisotropy tester under K0 condition - Google Patents

Abstract

Translated fromChinese

本发明提供一种K0条件下土体动力学参数及各向异性测定仪，其包括用于提供荷载的加载装置和模型箱，所述模型箱由用于存放待测土壤的容腔和可开启的腔盖构成，所述加载装置与模型箱的腔盖连接，所述模型箱的水平方向和竖直方向分别设有用于检测待测土壤剪切模量和压缩模量的压电传感器，所述模型箱的水平方向和竖直方向还设有用于检测待测土壤的水平土压力和竖直土压力的压力薄膜传感器，所述压电传感器与模型箱的安装处设置缓冲垫，所述腔盖上还设有用于检测待测土壤应力变化量的应变量检测装置，本发明提高了土体测量模量准确性及K0状态的力学响应，操作方便，可靠度高。

The invention provides a measuring instrument for soil dynamic parameters and anisotropy under K0 conditions, which includes a loading device for providing loads and a model box, and the model box is composed of a cavity for storing the soil to be tested and an openable The cavity cover of the model box is composed of, the loading device is connected with the cavity cover of the model box, and the horizontal direction and the vertical direction of the model box are respectively provided with piezoelectric sensors for detecting the shear modulus and compressive modulus of the soil to be measured, so The horizontal and vertical directions of the model box are also provided with a pressure film sensor for detecting the horizontal earth pressure and vertical earth pressure of the soil to be measured, and the installation of the piezoelectric sensor and the model box is provided with a buffer pad, and the cavity The cover is also equipped with a strain detection device for detecting the variation of the stress of the soil to be measured. The invention improves the accuracy of the soil measurement modulus and the mechanical response of the K0 state, and is easy to operate and has high reliability.

Description

Translated fromChinese

一种K0条件下土体动力学参数及各向异性测定仪An instrument for measuring soil dynamic parameters and anisotropy under K0 condition

技术领域technical field

本发明涉及一种土体基本力学参数及微观结构演化的装置和方法，特别是涉及一种K0条件下土体动力学参数及各向异性测定仪。The invention relates to a device and method for soil basic mechanical parameters and microstructure evolution, in particular to a soil dynamic parameter and anisotropy measuring instrument under K0 condition.

背景技术Background technique

砂土的最大动剪切模量和动压缩模量是土动力学最基本的两个参数，是岩土工程计算和设计方面非常重要的基本参数，而不同的土体颗粒在不同的荷载作用下也经历着微观结构的演化，而这一系列过程在基础设施的设计和建造之前必须在实验室里获得定量的分析，为将来工程的建造和运营中的安全性和耐久性的提高提供强有力的保证。目前，国内岩土工程室内实验里，测定最大动剪切模量通常用共振柱实验获得，由于共振柱本身的限制，首先它不能真正的获得最大动剪切模量和动压缩模量，已经有实验证明；其次它不能保证实验样本处在K0条件下，所以也不能真实反映现实条件下土的应力状态；最后由于共振柱实验过程非常繁琐，而且需要经验非常丰富的实验人员的操作才能获得可靠的数据。The maximum dynamic shear modulus and dynamic compression modulus of sandy soil are the two most basic parameters of soil dynamics, and are very important basic parameters in the calculation and design of geotechnical engineering, and different soil particles under different loads The environment is also undergoing the evolution of microstructure, and this series of processes must be quantitatively analyzed in the laboratory before the design and construction of infrastructure, which provides a strong foundation for the improvement of safety and durability in the construction and operation of future projects. strong guarantee. At present, in domestic geotechnical engineering laboratory experiments, the maximum dynamic shear modulus is usually obtained by the resonance column experiment. Due to the limitation of the resonance column itself, first of all, it cannot really obtain the maximum dynamic shear modulus and dynamic compression modulus. It has been proved by experiments; secondly, it cannot guarantee that the experimental samples are under the K0 condition, so it cannot truly reflect the stress state of the soil under realistic conditions; finally, because the resonant column experiment process is very cumbersome, and requires the operation of very experienced experimenters to obtain reliable data.

发明内容Contents of the invention

为了克服以上的技术不足，本发明的目的是提供一种室内测试K0状态下土体基本动力学参数以及土体微观结构演化的测定仪，适用于粘性土和非粘性土。In order to overcome the above technical deficiencies, the purpose of the present invention is to provide a kind of measuring instrument for indoor testing of soil basic dynamic parameters and soil microstructure evolution in K0 state, which is suitable for cohesive soil and non-cohesive soil.

本发明提供一种K0条件下土体动力学参数及各向异性测定仪，其包括用于提供荷载的加载装置和模型箱，所述模型箱由用于存放待测土壤的容腔和可开启的腔盖构成，所述加载装置与模型箱的腔盖连接，所述模型箱的水平方向和竖直方向分别设有用于检测待测土壤剪切模量和压缩模量的压电传感器，所述模型箱的水平方向和竖直方向还设有用于检测待测土壤的水平土压力和竖直土压力的压力薄膜传感器，所述压电传感器与模型箱的安装处设置缓冲垫，所述腔盖上还设有用于检测待测土壤应力变化量的应变量检测装置。The invention provides an instrument for measuring soil dynamic parameters and anisotropy under K0 conditions, which includes a loading device for providing loads and a model box, and the model box is composed of a cavity for storing the soil to be tested and an openable The cavity cover of the model box is formed, the loading device is connected with the cavity cover of the model box, and the horizontal direction and the vertical direction of the model box are respectively provided with piezoelectric sensors for detecting the shear modulus and compressive modulus of the soil to be measured, so The horizontal and vertical directions of the model box are also provided with a pressure film sensor for detecting the horizontal earth pressure and vertical earth pressure of the soil to be measured, and the installation of the piezoelectric sensor and the model box is provided with a buffer pad, and the cavity The cover is also provided with a strain detection device for detecting the variation of soil stress to be measured.

所述压电传感器为弯曲元压电传感器，其包括位于两端的振动发射器和振动接收器，所述压电传感器外接计算机。The piezoelectric sensor is a bending element piezoelectric sensor, which includes a vibration transmitter and a vibration receiver located at two ends, and the piezoelectric sensor is externally connected to a computer.

所述缓冲垫位于模型箱的外壁以及压电传感器的安装部之间。The buffer pad is located between the outer wall of the mold box and the mounting part of the piezoelectric sensor.

所述容腔由五块可拆卸安装的铝板构成。The cavity is composed of five detachable aluminum plates.

所述铝板上设有用于安装压电传感器的安装槽，所述压电传感器穿过安装槽固定连接。The aluminum plate is provided with a mounting groove for mounting the piezoelectric sensor, and the piezoelectric sensor is fixedly connected through the mounting groove.

所述压电传感器位于容腔外侧的部分与容腔外壁之间设有缓冲垫。A buffer pad is provided between the part of the piezoelectric sensor located outside the cavity and the outer wall of the cavity.

所述压电传感器位于容腔内部的部位包裹环氧树脂层。The portion of the piezoelectric sensor located inside the cavity is wrapped with an epoxy resin layer.

所述缓冲垫为硅胶材料制成。The buffer pad is made of silicone material.

所述腔盖的宽度小于容腔的宽度。The width of the cavity cover is smaller than the width of the cavity.

本发明的有益效果是：在模型箱的内部安装两对压电传感器，分别安装在水平方向和垂直方向，测定剪切模量和压缩模量；并在模型箱的水平方向和竖直方向贴上压力薄膜传感器，测定水平土压力和竖直土压力，并获得K0值的演化；模型箱顶部为加载装置以控制和在大小。本发明提供了在K0状态的土体的水平和竖直方向的剪切模量、压缩模量以及泊松比的计算所需的模型结构，进一步得到随着荷载的增加可以得到此过程中土体颗粒微观结构的变化，本发明提高了土体测量模量准确性及K0状态的力学响应，操作方便，可靠度高。The beneficial effects of the present invention are: two pairs of piezoelectric sensors are installed inside the model box, installed in the horizontal direction and vertical direction respectively, to measure the shear modulus and compression modulus; The upper pressure film sensor measures the horizontal earth pressure and vertical earth pressure, and obtains the evolution of the K0 value; the top of the model box is a loading device to control and adjust the size. The present invention provides the model structure required for the calculation of the horizontal and vertical shear modulus, compressive modulus and Poisson's ratio of the soil in the K0 state, and further obtains that the soil in this process can be obtained as the load increases. Changes in the microstructure of bulk particles, the invention improves the accuracy of soil measurement modulus and the mechanical response of the K0 state, and is easy to operate and high in reliability.

附图说明Description of drawings

图1是本发明的结构示意图。Fig. 1 is a structural schematic diagram of the present invention.

具体实施方式Detailed ways

下面结合附图对本发明实施例作进一步说明：Embodiments of the present invention will be further described below in conjunction with accompanying drawings:

如图1所示，本发明提供一种K0条件下土体动力学参数及各向异性测定仪，其包括用于提供荷载的加载装置和模型箱，所述模型箱由用于存放待测土壤的容腔和可开启的腔盖构成，所述加载装置与模型箱的腔盖连接，所述模型箱的水平方向和竖直方向分别设有用于检测待测土壤剪切模量和压缩模量的压电传感器，所述模型箱的水平方向和竖直方向还设有用于检测待测土壤的水平土压力和竖直土压力的压力薄膜传感器，所述压电传感器与模型箱的安装处设置缓冲垫，所述腔盖上还设有用于检测待测土壤应力变化量的应变量检测装置。As shown in Figure 1, the present invention provides a soil dynamic parameter and anisotropy tester under K0 condition, and it comprises the loading device that is used to provide load and model case, and described model case is used for storing the soil to be measured The cavity and the openable cavity cover are composed, the loading device is connected with the cavity cover of the model box, and the horizontal direction and the vertical direction of the model box are respectively provided for detecting the shear modulus and compression modulus of the soil to be measured. The piezoelectric sensor, the horizontal direction and the vertical direction of the model box are also provided with a pressure film sensor for detecting the horizontal earth pressure and vertical earth pressure of the soil to be measured, and the installation place of the piezoelectric sensor and the model box is set A buffer pad, the chamber cover is also provided with a strain detection device for detecting the variation of soil stress to be measured.

所述腔盖的宽度小于容腔的宽度，在加载装置提供的压力的作用，当容腔内放置待测砂土时，其腔盖在加载装置的作用下，向下移动，然后对待测砂土进行加压，而其上设有应变量检测装置，模型箱顶部为加载装置以控制荷载大小，而应变量检测装置可以用于记录轴向应变量变化，加载装置可以用气动装置，利用气压压迫腔盖，使得应变量检测装置实时检测应变量变化，加载装置也可以用其他能够提供压力的装置。The width of the chamber cover is smaller than the width of the chamber. Under the action of the pressure provided by the loading device, when the sand to be tested is placed in the chamber, the chamber cover moves downward under the action of the loading device, and then the sand to be tested The soil is pressurized, and there is a strain detection device on it. The top of the model box is a loading device to control the load, and the strain detection device can be used to record the change of the axial strain. The loading device can be a pneumatic device. Compressing the chamber cover enables the strain detection device to detect changes in the strain in real time, and the loading device can also use other devices that can provide pressure.

在模型箱的水平方向和竖直方向贴上压力薄膜传感器，测定水平土压力和竖直土压力，并获得K0值的演化：Paste pressure film sensors on the horizontal and vertical directions of the model box, measure the horizontal earth pressure and vertical earth pressure, and obtain the evolution of K0 value:

其中σ_h为水平土压力，σ_v为竖向土压力。 Where σ_h is the horizontal earth pressure, and σ_v is the vertical earth pressure.

所述压电传感器为Piezo System公司的T220-A4-303Y弯曲元压电传感器，其包括位于两端的振动发射器和振动接收器，所述压电传感器外接计算机。在模型箱的内部安装两对压电传感器，分别安装在水平方向和垂直方向，测定剪切模量和压缩模量。The piezoelectric sensor is the T220-A4-303Y bending element piezoelectric sensor of Piezo System Company, which includes a vibration transmitter and a vibration receiver at both ends, and the piezoelectric sensor is externally connected to a computer. Two pairs of piezoelectric transducers are installed inside the model box, respectively installed in the horizontal direction and vertical direction, to measure the shear modulus and compression modulus.

按照以下步骤获得微观结构的演化：Follow the steps below to obtain the evolution of the microstructure:

(1)G_ij＝V_ijs²ρ，其中G为剪切模量，V为剪切波速，i代表土颗粒的振动方向，j代表波的传播方向；(1) G_ij = V_ijs² ρ, where G is the shear modulus, V is the shear wave velocity, i represents the vibration direction of soil particles, and j represents the propagation direction of the wave;

(2)E_j＝V_j²ρ，其中M为弹性模量，V为压缩波速，j代表波的传播方向；(2) E_j = V_j² ρ, where M is the elastic modulus, V is the compression wave velocity, and j represents the propagation direction of the wave;

(3)其中υ为泊松比，i，j的意义与公式(1)中相同通过上述的计算，公式(4)，可以得到微观结构的演化参数FI。(3) Among them, υ is Poisson's ratio, and the meanings of i and j are the same as those in formula (1). Through the above calculation, formula (4), the evolution parameter FI of the microstructure can be obtained.

(4)$\mathrm{FI}=\sqrt{\frac{G_{\mathrm{VH}}/E_V}{G_{\mathrm{HH}}/E_H}}\×\sqrt{\frac{(1-{\mathrm{\ν}}_{\mathrm{hh}}-2{\mathrm{\ν}}_{\mathrm{vh}}{\mathrm{\ν}}_{\mathrm{hv}})}{2(1-{{\mathrm{\ν}}_{\mathrm{hh}}}^2)}},$FI为组构指数，表示微观(4)$\mathrm{FI}=\sqrt{\frac{G_{\mathrm{VH}}/{\mathrm{E.}}_V}{G_{\mathrm{HH}}/{\mathrm{E.}}_h}}\×\sqrt{\frac{(1-{\mathrm{\ν}}_{\mathrm{hh}}-2{\mathrm{\ν}}_{\mathrm{vh}}{\mathrm{\ν}}_{\mathrm{hv}})}{2(1-{{\mathrm{\ν}}_{\mathrm{hh}}}^2)}},$ FI is the fabric index, indicating microcosmic

结构的演化，波的水平传播用H表示，竖向用V表示，以下意义相同。The evolution of the structure, the horizontal propagation of the wave is represented by H, and the vertical is represented by V, the following meanings are the same.

然后利用公式(5)或(6)可以反算出各向异性指数a，Then use the formula (5) or (6) to back calculate the anisotropy index a,

(5)$\frac{E_v}{E_h}=\frac{{(5+a)}^2(14-6a+{21}_{\mathrm{\χ}}-15a_{\mathrm{\χ}})}{{(5-3a)}^2(14-2a+{21}_{\mathrm{\χ}}+{9a}_{\mathrm{\χ}})};$(5)$\frac{{\mathrm{E.}}_v}{{\mathrm{E.}}_h}=\frac{{(5+a)}^2(14-6a+{\mathrm{twenty\; one}}_{\mathrm{\χ}}-15a_{\mathrm{\χ}})}{{(5-3a)}^2(14-2a+{\mathrm{twenty\; one}}_{\mathrm{\χ}}+{9a}_{\mathrm{\χ}})};$

(6)$\frac{G_{\mathrm{vh}}\left(G_{\mathrm{hv}}\right)}{G_{\mathrm{hh}}}=\frac{{(5+a)}^2(21-11a+{14}_{\mathrm{\χ}}-{10a}_{\mathrm{\χ}})}{\left[10(5-a)(105-46a-23a^2+{70}_{\mathrm{\χ}}-{24a}_{\mathrm{\χ}}+{{2a}^2}_{\mathrm{\χ}})\right]},$其中χ为颗粒切向刚度与法向刚度的比值，一般取0.5。(6)$\frac{G_{\mathrm{vh}}\left(G_{\mathrm{hv}}\right)}{G_{\mathrm{hh}}}=\frac{{(5+a)}^2(\mathrm{twenty\; one}-11a+{14}_{\mathrm{\χ}}-{10a}_{\mathrm{\χ}})}{\left[10(5-a)(105-46a-\mathrm{twenty\; three}{a}^2+{70}_{\mathrm{\χ}}-{\mathrm{twenty\; four}a}_{\mathrm{\χ}}+{{2a}^2}_{\mathrm{\χ}})\right]},$ Where χ is the ratio of particle tangential stiffness to normal stiffness, generally 0.5.

本发明提供了在K0状态的土体的水平和竖直方向的剪切模量、压缩模量以及泊松比的计算所需的模型结构，进一步得到随着荷载的增加可以得到此过程中土体颗粒微观结构的变化。The present invention provides the model structure required for the calculation of the horizontal and vertical shear modulus, compressive modulus and Poisson's ratio of the soil in the K0 state, and further obtains that the soil in this process can be obtained as the load increases. changes in the microstructure of the particles.

所述缓冲垫位于模型箱的外壁以及压电传感器的安装部之间。The buffer pad is located between the outer wall of the mold box and the mounting part of the piezoelectric sensor.

所述容腔由五块可拆卸安装的铝板构成，模型箱由5片可拆卸的厚度为2cm的刚性铝板组成，以保证土体在K0状态下；腔盖的较模型箱的敞口小1mm以利于自由加载。The cavity is composed of five detachable aluminum plates, and the model box is composed of five detachable rigid aluminum plates with a thickness of 2cm to ensure that the soil is in the K0 state; the cavity cover is 1mm smaller than the opening of the model box for free loading.

所述铝板上设有用于安装压电传感器的安装槽，所述压电传感器穿过安装槽固定连接。模型箱相对的铝板上钻出安装槽来安装弯曲元压电传感器，两对弯曲元压电传感器表面必须用环氧树脂均匀涂上，达到防水和防腐的效果，而且在固定弯曲元压电传感器时要在铝板和传感器之间涂硅胶来达到隔振，使得振动发射器按照既定路线的方向发射。同时将硅胶作为缓冲垫使用，可以避免振动发射器产生的共振使得模型箱发生振动，影响检测数据的准确性。The aluminum plate is provided with a mounting groove for mounting the piezoelectric sensor, and the piezoelectric sensor is fixedly connected through the mounting groove. Drill installation slots on the opposite aluminum plate of the model box to install the bending element piezoelectric sensors. The surfaces of the two pairs of bending element piezoelectric sensors must be evenly coated with epoxy resin to achieve waterproof and anti-corrosion effects. At the same time, silica gel should be applied between the aluminum plate and the sensor to achieve vibration isolation, so that the vibration transmitter can be launched in the direction of the established route. At the same time, the use of silica gel as a cushion can prevent the resonance generated by the vibration transmitter from causing the model box to vibrate and affect the accuracy of the detection data.

所述压力薄膜传感器的表面涂抹环氧树脂，起到防水和防腐的作用，避免传感器长时间与待测土壤接触导致的腐蚀。The surface of the pressure film sensor is coated with epoxy resin to play the role of waterproof and anti-corrosion, and avoid the corrosion caused by the sensor being in contact with the soil to be measured for a long time.

实施例不应视为对本发明的限制，但任何基于本发明的精神所作的改进，都应在本发明的保护范围之内。The embodiments should not be regarded as limiting the present invention, but any improvement based on the spirit of the present invention should be within the protection scope of the present invention.

Claims (9)

Translated fromChinese

1.一种KO条件下土体动力学参数及各向异性测定仪，其特征在于：其包括用于提供荷载的加载装置和模型箱，所述模型箱由用于存放待测土壤的容腔和可开启的腔盖构成，所述加载装置与模型箱的腔盖连接，所述模型箱的水平方向和竖直方向分别设有用于检测待测土壤剪切模量和压缩模量的压电传感器，所述模型箱的水平方向和竖直方向还设有用于检测待测土壤的水平土压力和竖直土压力的压力薄膜传感器，所述压电传感器与模型箱的安装处设置缓冲垫，所述腔盖上还设有用于检测待测土壤应力变化量的应变量检测装置。1. soil dynamics parameter and anisotropy measuring instrument under a kind of KO condition, it is characterized in that: it comprises the loading device and the model box that are used to provide load, and described model box is used to deposit the cavity of soil to be measured It is composed of an openable chamber cover, the loading device is connected with the chamber cover of the model box, and the horizontal and vertical directions of the model box are respectively equipped with piezoelectric Sensor, the horizontal and vertical directions of the model box are also provided with a pressure film sensor for detecting the horizontal earth pressure and vertical earth pressure of the soil to be measured, and the installation of the piezoelectric sensor and the model box is provided with a buffer pad, The chamber cover is also provided with a strain detection device for detecting the variation of soil stress to be measured.2.根据权利要求1所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述压电传感器为弯曲元压电传感器，其包括位于两端的振动发射器和振动接收器，所述压电传感器外接计算机。2. soil dynamics parameter and anisotropy measuring instrument under a kind of KO condition according to claim 1, it is characterized in that, described piezoelectric sensor is bending element piezoelectric sensor, and it comprises the vibration emitter that is positioned at two ends and a vibration receiver, the piezoelectric sensor is externally connected to a computer.3.根据权利要求1所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述缓冲垫位于模型箱的外壁以及压电传感器的安装部之间。3. The instrument for measuring soil dynamic parameters and anisotropy under a kind of KO condition according to claim 1, characterized in that, the buffer pad is located between the outer wall of the model box and the installation part of the piezoelectric sensor.4.根据权利要求1所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述容腔由五块可拆卸安装的铝板构成。4. The instrument for measuring soil dynamic parameters and anisotropy under a kind of KO condition according to claim 1, characterized in that, the cavity is composed of five detachably installed aluminum plates.5.根据权利要求4所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述铝板上设有用于安装压电传感器的安装槽，所述压电传感器穿过安装槽固定连接。5. soil dynamics parameter and anisotropy measuring instrument under a kind of KO condition according to claim 4, it is characterized in that, described aluminum plate is provided with the installation groove that is used to install piezoelectric sensor, and described piezoelectric sensor Fasten the connection through the mounting slot.6.根据权利要求5所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述压电传感器位于容腔外侧的部分与容腔外壁之间设有缓冲垫。6. The soil dynamics parameter and anisotropy measuring instrument under a kind of KO condition according to claim 5, is characterized in that, a buffer is provided between the part outside the cavity and the outer wall of the cavity of the piezoelectric sensor pad.7.根据权利要求1、2、5或6所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述压电传感器位于容腔内部的部位包裹环氧树脂层。7. The soil dynamic parameters and anisotropy measuring instrument under a kind of KO condition according to claim 1, 2, 5 or 6, is characterized in that, the position of the piezoelectric sensor located inside the cavity is wrapped with epoxy resin layer.8.根据权利要求1所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述缓冲垫为硅胶材料制成。8. The soil dynamic parameters and anisotropy measuring instrument under a kind of KO condition according to claim 1, characterized in that, the buffer pad is made of silica gel material.9.根据权利要求1所述的一种KO条件下土体动力学参数及各向异性测定仪，其特征在于，所述腔盖的宽度小于容腔的宽度。9. The instrument for measuring soil dynamic parameters and anisotropy under a KO condition according to claim 1, wherein the width of the chamber cover is smaller than the width of the chamber.