CN-122016426-A - Device and method for testing early settlement stability of HECC material rock-fill dam panel

CN122016426ACN 122016426 ACN122016426 ACN 122016426ACN-122016426-A

Abstract

The application relates to a HECC material rockfill dam panel early settlement stability test device and method. The device comprises an angle adjusting bracket, a panel die, a movable baffle, a movable reinforcing steel bar net, a movable pressing plate and a settlement monitoring device. When a stability test is carried out, the movable reinforcing steel bar net is placed in a pouring groove of the simulation panel, HECC materials are poured, the HECC material simulation panel is formed after trowelling through the movable pressing plate, the movable baffle is placed on the top surface of the HECC material simulation panel, the early settlement condition of the HECC material simulation panel is monitored through the settlement monitoring device, a HECC material time-settlement relation curve is obtained, the settlement ratio is calculated, the settlement stability of the HECC material is determined through the settlement ratio, and therefore the lifting speed of a matched sliding mode is selected during construction, so that the flatness and the related performance of the panel are ensured. The application effectively simulates the engineering construction working condition of the HECC material, accurately characterizes the early sedimentation stability of the HECC material, and provides theoretical guidance for the application of the HECC material in the concrete engineering of the panel.

Inventors

Diao Muguang
HUO JINYANG
HUANG GANG
SUN MINGLUN
LV XINGDONG
CHEN XIANG
ZHANG XIUZHEN
SHAO GUOWEI
Wang Aohua
LI JIAZHENG
ZHANG XINRU
SHI YAN
TANG WEIJIE

Assignees

中国三峡建工(集团)有限公司
长江水利委员会长江科学院

Dates

Publication Date: 20260512
Application Date: 20260205

Claims (8)

1. A test device for early settlement stability of a HECC material rock-fill dam panel is characterized by comprising an angle adjusting bracket (3), a panel die (1), a movable baffle plate (2), a movable reinforcing steel bar net (6), a movable pressing plate (7) and a settlement monitoring device (5), wherein the panel die (1) is arranged on the angle adjusting bracket (3), the inclination angle of the panel die is adjusted through the angle adjusting bracket (3), the adjusting range is controlled to be 20-75 degrees, a simulated panel pouring groove (4) is formed in a panel of the panel die (1), the settlement monitoring device (5) comprises a control device and a displacement sensor fixedly arranged on the inner top surface of the simulated panel pouring groove (4), when the early settlement stability test of the HECC material rock-fill dam panel is carried out, the movable reinforcing steel bar net (6) is arranged in the simulated panel pouring groove (4), HECC material is poured into the simulated panel pouring groove (4), after a notch is flattened through the movable pressing plate (7), a HECC material simulated panel (8) is formed in the simulated panel (4), the thickness of the simulated panel (2) between the top surface of the simulated panel (8) and the simulated panel is larger than the thickness of the simulated baffle plate (2), and monitoring the early sedimentation condition of the HECC material simulation panel (8) through the sedimentation monitoring device (5).
2. The early settlement stability testing device for the HECC material rock-fill dam panel is characterized in that the settlement monitoring device (5) comprises 2 laser displacement sensors which are fixed at the inner top of a simulated panel pouring groove (4) and can continuously read, the signal output ends of the laser displacement sensors are connected with the signal input end of a control device, the displacement data of a movable pressing plate (7), namely the settlement data of the HECC material simulated panel (8), are continuously collected through the two laser displacement sensors, the collected displacement data are transmitted to the control device, the time is set through the control device, a HECC material simulated panel time-settlement curve is generated, settlement parameters are obtained from the HECC material simulated panel time-settlement relation curve, and differential settlement quantity delta S and settlement ratio delta are calculated.
3. The device for testing the early settlement stability of the face plate of the rock-fill dam made of HECC material according to claim 1 or 2, wherein the angle adjusting bracket (3) comprises a supporting bottom plate and an adjusting bracket, and the face plate die (1) is rotatably connected with the supporting bottom plate and is supported and adjusted in angle through the adjusting bracket so as to change the angle of a simulated slope.
4. The early settlement stability testing device for the rock-fill dam panel of the HECC material according to claim 1 or 2, wherein the length of the movable reinforcing mesh (6) is smaller than the length of the simulation panel pouring groove (4), and the movable reinforcing mesh (6) is completely wrapped by the HECC material when the HECC material is poured to form the HECC material simulation panel (8).
5. The early settlement stability testing device for the HECC material rock-fill dam panel according to claim 1 or 2 is characterized in that the width and the length of the movable baffle plate (2) are respectively matched with the depth and the width of the simulated panel pouring groove (4), the width of the movable pressing plate (7) is matched with the width of the simulated panel pouring groove (4), the length is smaller than the length of the simulated panel pouring groove (4), and handles (8) are respectively arranged on the movable baffle plate (2) and the movable pressing plate (7).
6. A method for testing the early settlement stability of a rock-fill dam panel made of HECC material is characterized in that the testing method uses the testing device for testing the early settlement stability of the rock-fill dam panel made of HECC material according to any one of claims 1 to 5 before pouring the rock-fill dam panel made of HECC material, simulation and stability test are carried out on the HECC material rock-fill dam panel to be poured, and the concrete steps are as follows: S1, determining the actual gradient of a rock-fill dam panel made of HECC material to be poured, and preparing a slurry body made of HECC material, which is the same as the actual rock-fill dam panel made of HECC material to be poured, according to design requirements; S2, adjusting a panel die to the actual gradient of the to-be-poured HECC material rockfill dam panel through an angle adjusting bracket, pouring the HECC material slurry stirred in the step S1 into a simulation panel pouring groove of the panel die, and forming a HECC material simulation panel through layered pouring of a movable pressing plate fixing surface in the pouring process, wherein the top surface of the HECC material simulation panel is a certain distance away from the inner top surface of the simulation panel pouring groove and is used for installing a movable baffle; s3, inserting the movable baffle into the simulated panel pouring groove, and enabling the movable baffle to be closely attached to the top surface of the HECC material simulated panel which is just poured and formed; s4, opening the monitoring device, removing the movable pressing plate, continuously monitoring displacement data of the movable baffle through the displacement sensor, setting fixed time, and continuously recording the displacement data of the movable baffle, so as to obtain a time-sedimentation relation curve of the HECC material simulation panel; S4, obtaining sedimentation parameters from the HECC material simulation panel, namely an initial sedimentation value S 0 , an instant sedimentation quantity S t and the length L of the HECC material simulation panel, calculating a differential sedimentation quantity delta S and a sedimentation ratio delta through the sedimentation parameters, judging early sedimentation stability of the HECC material simulation panel through the sedimentation ratio delta, and selecting a matched sliding mode lifting speed of the rock-fill dam panel to perform pouring of the actual HECC material rock-fill dam panel.
7. The method for testing the early settlement stability of the HECC material rock-fill dam panel according to claim 6, wherein in the step S4, the specific formulas for calculating the differential settlement quantity DeltaS and the settlement ratio delta through the settlement parameters are as follows: ; 。
8. The method for testing early settlement stability of a rock-fill dam panel made of HECC material according to claim 6 or 7, wherein the specific criteria for judging the early settlement stability of the rock-fill dam made of HECC material in the step S4 by the numerical value of the settlement ratio delta are as follows: the stability of the HECC material simulation panel is judged to be A level, and the sliding mode lifting speed of the rock-fill dam panel is not more than 3m/h; judging the stability of the HECC material simulation panel to be B level, wherein the sliding mode lifting speed of the rock-fill dam panel is not more than 2m/h; And 4 per mill, judging the stability of the HECC material simulation panel to be C level, wherein the sliding mode lifting speed of the rock-fill dam panel is not more than 1.2m/h.

Description

Device and method for testing early settlement stability of HECC material rock-fill dam panel Technical Field The application relates to the field of hydraulic high-ductility concrete performance test, in particular to a device and a method for testing early settlement stability of a rock-fill dam panel made of HECC (high-strength concrete) materials. Background The concrete face rockfill dam is a common name of a dam which is filled by stacking rocks or sand gravel in a layered rolling way and takes a concrete face plate as an impermeable body, and is widely applied to water retaining buildings of water conservancy and hydropower engineering in recent years. The concrete face plate in the concrete face plate rock-fill dam is used as a main seepage-proofing structure of the dam body, bears a larger head drop and is important for the safety and stability of dam seepage. The mechanical property of the concrete is obviously asymmetric, the compressive strength of the concrete is far higher than the tensile strength, and brittle fracture is easy to occur under the tensile and compression states, so that the deformation of the dam body and the panel concrete caused by dam body settlement is uncooled, the panel concrete is easy to crack, and the safety and the stability of the dam body are further influenced. At present, the later deformation and control of the concrete panel are the main means for preventing cracking, however, the passive deformation control method can only solve the cracking problem of the panel at a certain stage, and the cracking of the concrete panel still occurs throughout the whole operation period of the panel. In order to solve the problem of cracking of the concrete panel, the inventor of the present application studied a hydraulic ultrahigh-toughness cement-based composite material suitable for hydraulic construction, and applied for an application patent in 2022, 3 and 23, and issued publication number CN114685117B. The patent discloses a formula and a preparation method of the material, wherein the material comprises 25-34 wt% of cement, 23-30 wt% of fly ash, 15-20 wt% of silica fume, 26-32 wt% of fine aggregate, 1.25-1.7 wt% of composite fiber net sheet, 0.1-0.24 wt% of water reducing agent and 0.03-0.07 wt% of thickening agent, and the composite fiber net sheet is prepared by immersing composite fibers in aqueous epoxy resin and a curing agent, uniformly mixing, taking out the composite fibers, spreading, and cutting or crushing the composite fibers into small-piece net structures. The material is characterized in that on the basis of the traditional high-ductility fiber reinforced cement-based composite material (ENGINEERED CEMENTITIOUS COMPOSITE, ECC) material, the ground-edge material is adopted to break through the grain size of aggregate, and the fluidity design is carried out according to the requirement, so that the material has the performance advantages of high ductility, high toughness, high durability and the like, therefore, the material is named as the hydraulic ultrahigh-toughness cement-based composite material (Hydraulic Engineered Cementitious Composite, HECC for short) suitable for hydraulic buildings, and the HECC material is tightly and serially interweaved with other raw materials by adding the composite fiber mesh, so that the cracking resistance, the impermeability and the mechanical strength such as high compression resistance and fracture resistance are obviously improved, and the material is very suitable for being used in hydraulic engineering at the positions with the requirements of seepage resistance and crack resistance. The HECC material has been applied in the face rockfill dam, and particularly, the HECC panel is used for replacing the traditional concrete panel, so that the stress distribution of the panel can be remarkably improved, the deformation adaptability of the panel is improved, and the occurrence of panel cracks can be effectively prevented. When the face plate of the common rock-fill dam is poured on the inclined plane of the dam body, a sliding mode system is arranged on the inclined plane of the dam bottom, concrete is continuously poured and rammed along the track, and the template is slid and lifted at a constant speed, so that the face plate is formed compactly at one time. However, because HECC is made up of cement, mineral admixture, fine sand, fiber, admixture and water, etc., do not contain coarse aggregate, belong to cement mortar class, it lacks the coarse aggregate skeleton, in using the slip form to construct the course continuously, its slip form construction speed directly influences HECC panel shaping effect, slip form construction speed is unsuitable, if slip form construction speed is too fast, subside on the slope easily, produce the swell even plastic crack, influence quality and operation security of the panel. Because the HECC material is a novel material, at present, excessive researches on the performance test of