JP4229562B2 - Deterioration detection method for concrete structures - Google Patents
Deterioration detection method for concrete structures Download PDFInfo
- Publication number
- JP4229562B2 JP4229562B2 JP2000025121A JP2000025121A JP4229562B2 JP 4229562 B2 JP4229562 B2 JP 4229562B2 JP 2000025121 A JP2000025121 A JP 2000025121A JP 2000025121 A JP2000025121 A JP 2000025121A JP 4229562 B2 JP4229562 B2 JP 4229562B2
- Authority
- JP
- Japan
- Prior art keywords
- concrete
- deterioration
- carrier
- fluorescent
- fluorescent carrier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
Description
【0001】
【発明の属する技術分野】
本発明は、主としてコンクリート構造物の劣化検知方法およびコンクリート構造物に関する。
【0002】
【従来の技術及び発明が解決しようとする課題】
コンクリート構造物の劣化調査の方法としては、構造物から直接コアー供試体を採り、その強度を圧縮試験で調べる方法と、構造物の表面に現れたひび割れの形状と割れ幅を目視調査したり、超音波の伝播速度を測定してその劣化の程度を推定する方法がある。通常は、破壊検査である前者よりも、後者の形で定期検査などが行われているが、長大橋を例にとれば、管理の為の通路が確保されていない場合は、船上から双眼鏡を使って調査したり、あるいは実際に足場を架設して始めて調査にかかるなど、目視検査の為に費やす労力とコストは構造物を管理する側の大きな負担となっている。
【0003】
最近では、応力やひび割れの発生が予測される箇所に歪みゲージを貼り付け、ひび割れを電気的に検出する方法や、光ファイバーを使って変位を光学的に計測する技術も開発されてはいるが、測定個所が点又は部分的であり、構造物全体にわたる検査は困難であった。
【0004】
そこで、本発明は、コンクリート構造物全体にわたって劣化調査を容易に行うための劣化検知方法および劣化検知が容易なコンクリート構造物を提供することを課題とする。
【0005】
【課題を解決するための手段】
本発明者らは、鋭意研究した結果、コンクリート構造物の劣化調査に有効な、新規な方法を発見した。これは、フラクトルミネッセンスを応用することにより、コンクリート構造物に起こった劣化を、「部分」的な視点でなく「面」としての視点で検知することができるものである。
【0006】
即ち、本発明の解決手段は、フラクトルミネッセンスを生じる蛍光担体をコンクリート表面に付着させ、コンクリートの破損に伴ない前記蛍光担体から発せられた蛍光によって、コンクリートの劣化を検知することを特徴とするコンクリート構造物の劣化検知方法にある。
【0007】
フラクトルミネッセンスとは、物体が破損する時に生じるエネルギーで周りの原子を励起し、励起された電子が再び基底状態に復帰するときに解放するエネルギーが蛍光となって現れる現象を言う。
コンクリート構造物が耐力の限界に達すると、引っ張り応力に耐えきれなくなったコンクリートの表面に先ず微細な亀裂が起こる。この場合に、該コンクリートの表面がフラクトルミネッセンスを起こす蛍光担体によって覆われていれば、このような亀裂によるエネルギーによって該蛍光担体が蛍光を発する。
従って観察者は、微細な表面の亀裂ではなく、そこから発せられる蛍光色により亀裂を観察することができ、かかる蛍光色を発している部分に耐力の限界となる程度の力が働いたことが分かる。
【0008】
前記フラクトルミネッセンスを起こす蛍光物質としては、ユーロピウムなどに例示される希土類元素が挙げられる。
希土類元素が蛍光を生ずるためには、希土類元素単独で付着されるよりも、結晶構造体等を担体として該担体に希土類元素が添加されたもの(以下、「蛍光担体」という)としてコンクリート表面に付着されていることが好ましい。
担体としては、長石及びBaFXなどの結晶構造体やガラス相、又はこれらの複合物などが例示される。
【0009】
【発明の実施の形態】
以下、本発明の一実施形態について説明する。
まず、長石の構成元素に希土類元素を添加して焼成することにより蛍光担体を作製し、該蛍光担体を粉砕することにより、粉末状の蛍光担体とする。
かかる蛍光担体の粉末は、色々な手段でコンクリート構造物の表面に塗布することができるが、より確実に劣化を検知するためにはコンクリート表面に密着させて均一に塗布することが望ましく、その為には、例えば以下の2つの方法によって塗布することが好ましい。
【0010】
まず、第1の方法としては、前記蛍光担体をメチルシロキサンなどに例示されるガラス系塗料、又はアクリル樹脂などに例示される有機塗料に混ぜた後、コンクリート構造物の表面に刷毛塗り又は吹き付け塗装の方法で塗りつけるものである。
【0011】
第2の方法としては、前記蛍光担体を同様に塗料に混ぜた後、予めコンクリート型枠の内側表面に塗りつけるか、或いは蛍光担体を含む薄膜を予め作製して型枠の内側表面に張っておき、コンクリート打設後、型枠を脱型する際に型枠の表面から構造物の表面に転写させる方法である。
【0012】
観察者が色として亀裂を観察するためには、蛍光担体が長時間に亘り残光を出し続けることが望ましい。
このような残光を出し続けやすい担体の構造例としては、SrA12O4、CaA12O4などの結晶構造体が挙げられる。
【0013】
また、検知計器や環境によっては特定の波長が検知に有効な場合があり、この場合には、色彩の変化については多数の電子準位を持つ希土類元素イオン、例えばPr3+、Er3+などを使用することで、発色光の波長を調整することができる。
【0014】
表1は、長石の構成元素と希土類元素との組成、およびそのフラクトルミネッセンスの色を示したものである。
【0015】
【表1】
【0016】
また、コンクリート構造物表面に蛍光が生じた際に、一般の人に不安を与えない工夫を施した方が好ましい場合もあると考えられる。このような場合には、二次的に紫外光線又は赤外光線を当てて初めて検出が可能となる方法を採用することが好ましく、即ちBaFX(Xはハロゲン元素を示す)を担体として、該担体にEu2+を添加した蛍光担体に見られる揮尽発光を利用することにより実現できる。
ここで、揮尽発光とは、蛍光の一時的な発光が終わった後、紫外光線または赤外光線を照射することによって再び励起されると、貯えられていたエネルギーが全て蛍光となって再び発光する現象をいう。
【0017】
揮尽発光を利用すれば、コンクリート構造物の劣化検査を行う際に、紫外光線等を照射することによって蛍光が生じるため、一般の人に不安を与えないだけでなく構造物を管理する者にとっても検査しやすいものとなる。
【0018】
また、コンクリートの表面の亀裂は必ずしも構造物の耐力の限界ばかりで生じるものではない。例えば、コンクリート中の塩分による鉄筋腐食膨張によって亀裂が生じることもある。この場合には、亀裂、即ち蛍光がコンクリート中に配筋した鉄筋に沿った形で発生する為、劣化の原因が該鉄筋の腐食膨張であることを推定するのが容易となる。従って、構造物の管理者は、コンクリ−トをはつり修復する時期を蛍光により適確に判断することができる。
【0019】
上記実施形態では、蛍光担体を粉砕して粉末とし、かかる粉末をコンクリート表面に塗布する方法について説明したが、本発明はこれに限定されるものではない。
【0020】
他の実施形態としては、例えば蛍光担体を粒径0.5mm程度の粒状に調製し、さらにセメントと混ぜてモルタルとすることにより、該モルタルをコンクリート表面に塗布することなどが例示できる。
【0021】
以下、本発明の実施例について説明する。
【0022】
まず、蛍光担体の粉末を以下のようにして作製した。
即ち、蛍光担体の原料を、表1に示したNo.1の組成となるように秤量し混合した後、アルミナ坩堝中に入れ、該アルミナ坩堝を顆粒状炭素で満たした一回り大きいアルミナ坩堝の中に入れ蓋をした。この坩堝を電気炉に入れ、室温から1800℃まで3時間をかけて昇温し、さらに1800℃で2時間保持して原料を溶融し、1600℃まで2時間かけて徐冷し、その後室温までを炉内放冷して試料1とした。
かかる試料1について粉末X線回折の測定を行うことによって、長石の結晶構造の一つであるヘキサゴナルセルシアンと同定された。
さらに、試料1をボールミルによって粉砕し、蛍光担体1とした。
【0023】
フラクトルミネッセンスを応用し、コンクリート構造物に起こった劣化を面で検知した実施例を次に示す。
【0024】
実施例1
<供試体の作製>
塗装材としてメチルシロキサンを使用し、蛍光担体1を、100g/Lの割合でボールミルで混合した。かかる混合物を、円筒型(10cmφ×20cm)のコンクリート供試体の側面に刷毛を使って塗布した。
<試験および結果>
該コンクリート供試体に、圧縮試験機により上下方向から圧縮力を作用させると、破壊時に該コンクリート供試体の表面に蛍光が生じるのが観察された。高速度写真とコンクリート供試体との破断面を照らし合わせてみると、破断の基点と見なされる位置から順に蛍光が発せられたことが分かった。
【0025】
実施例2
<供試体の作製>
アクリル塗料に蛍光担体1を200g/Lの割合で混合した。あらかじめ作成しておいた板状の橋梁モデル(100cm×30cm×3cm)の床板コンクリート供試体の下面に、前記蛍光担体1が混合されたアクリル塗料を吹き付け塗装した。
<試験および結果>
前記床板コンクリート供試体を上面より載荷すると、床板コンクリート供試体の中央部に蛍光が生じ、コンクリート供試体下面中央に床板の長手方向と直角の向きにひび割れが発生した。
あらかじめ埋め込んでおいた歪み計の解析から、蛍光を目視確認した位置とひび割れの位置は一致した。
【0026】
実施例3
<供試体の作製>
塩害によるコンクリート劣化の指標としてのフラクトルミネッセンス機能実験を行うために、鉄筋を配筋したコンクリート板状供試体の片側の面に実施例2と同じ塗装を施した。
<試験および結果>
かかるコンクリート板状供試体に、飽和食塩水を間欠的に噴霧する塩害促進試験器に入れ、塩害を起こさせて蛍光を観測した。
蛍光は鉄筋に沿う形で観測されたが、やがてその位置にひび割れが現れた。検査の結果、鉄筋が錆によって膨張したこと、即ち典型的な塩害によるコンクリート表面のひび割れが原因となって生じた劣化であることが確認できた。
【0027】
【発明の効果】
本発明によれば、コンクリート構造物が耐力の限界に達すると、引っ張り応力に耐えきれなくなったコンクリートの表面に先ず微細な亀裂が走るが、かかる亀裂部から蛍光が発せられることにより亀裂を全体的な面として容易に検知することができる。
実際には、例えばコンクリート長大橋の橋桁下面に蛍光担体を塗布し、色彩の変化を観察することで、橋の健全度を確かめることができるため、従来のひび割れパターンの目視詳細観察による定期検査に代わるモニタリング方式として有効である。[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to a method for detecting deterioration of a concrete structure and a concrete structure.
[0002]
[Prior art and problems to be solved by the invention]
As a method for investigating the deterioration of concrete structures, take a core specimen directly from the structure and examine its strength by a compression test, visually inspect the shape and width of cracks that appeared on the surface of the structure, There is a method of estimating the degree of deterioration by measuring the propagation speed of ultrasonic waves. Normally, periodic inspections are conducted in the latter form rather than the former, which is a destructive inspection.However, taking the long bridge as an example, if a passage for management is not secured, binoculars are used from the ship. The labor and cost spent for visual inspection, such as surveying using the system or starting a survey after actually constructing a scaffold, is a heavy burden on the side managing the structure.
[0003]
Recently, strain gauges have been attached to places where stress and cracks are expected to occur, and a method for electrically detecting cracks and a technique for optically measuring displacement using optical fibers have been developed. The measurement location was point or partial and inspection across the entire structure was difficult.
[0004]
Therefore, an object of the present invention is to provide a deterioration detection method for easily performing a deterioration investigation over the entire concrete structure and a concrete structure in which the deterioration detection is easy.
[0005]
[Means for Solving the Problems]
As a result of intensive studies, the present inventors have discovered a novel method effective for investigating the deterioration of concrete structures. By applying fractoluminescence, it is possible to detect deterioration that has occurred in a concrete structure from the viewpoint of a “surface” rather than a “partial” viewpoint.
[0006]
That is, the solution of the present invention is characterized in that a fluorescent carrier that generates fructoluminescence is attached to the concrete surface, and the deterioration of the concrete is detected by the fluorescence emitted from the fluorescent carrier due to the breakage of the concrete. There is a method for detecting deterioration of structures.
[0007]
Fractoluminescence is a phenomenon in which surrounding atoms are excited by energy generated when an object is broken, and energy released when the excited electrons return to the ground state again appears as fluorescence.
When the concrete structure reaches the limit of proof stress, a fine crack first occurs on the surface of the concrete that cannot withstand the tensile stress. In this case, if the surface of the concrete is covered with a fluorescent carrier that generates fructoluminescence, the fluorescent carrier emits fluorescence by the energy generated by such cracks.
Therefore, the observer can observe the cracks not by the fine cracks on the surface but by the fluorescent color emitted from the cracks, and the force that is the limit of the proof stress is applied to the part emitting such fluorescent colors. I understand.
[0008]
Examples of the fluorescent substance that causes the fructoluminescence include rare earth elements exemplified by europium.
In order for the rare earth element to generate fluorescence, rather than being deposited alone, the rare earth element is added to the surface of the concrete as a carrier with a crystal structure or the like added to the carrier (hereinafter referred to as “fluorescent carrier”). It is preferable that it adheres.
Examples of the carrier include crystal structures such as feldspar and BaFX, a glass phase, or a composite thereof.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described.
First, a fluorescent carrier is prepared by adding a rare earth element to a constituent element of feldspar and firing, and the fluorescent carrier is pulverized to obtain a powdery fluorescent carrier.
Such a fluorescent carrier powder can be applied to the surface of a concrete structure by various means. However, in order to detect the deterioration more reliably, it is desirable that the powder is applied in close contact with the concrete surface. For example, it is preferably applied by the following two methods.
[0010]
First, as a first method, the fluorescent carrier is mixed with a glass-based paint exemplified by methyl siloxane or the like, or an organic paint exemplified by acrylic resin, and then applied to the surface of the concrete structure by brush painting or spray painting. The method of painting.
[0011]
As a second method, after the fluorescent carrier is similarly mixed with the paint, it is applied to the inner surface of the concrete mold in advance, or a thin film containing the fluorescent carrier is prepared in advance and stretched on the inner surface of the mold. This is a method of transferring from the surface of the mold to the surface of the structure when the mold is removed after casting the concrete.
[0012]
In order for an observer to observe a crack as a color, it is desirable that the fluorescent carrier continues to emit afterglow for a long time.
Examples of the structure of the carrier that easily keeps afterglow include crystal structures such as SrA1 2 O 4 and CaA1 2 O 4 .
[0013]
In addition, a specific wavelength may be effective for detection depending on the detection instrument and environment. In this case, rare earth ions having a large number of electron levels, such as Pr 3+ and Er 3+ , for color change. Can be used to adjust the wavelength of the colored light.
[0014]
Table 1 shows the composition of constituent elements of feldspar and rare earth elements, and the color of their fructoluminescence.
[0015]
[Table 1]
[0016]
In addition, when fluorescence occurs on the surface of a concrete structure, it may be preferable to devise a measure that does not cause anxiety to ordinary people. In such a case, it is preferable to adopt a method that enables detection only after secondary irradiation with ultraviolet rays or infrared rays, that is, using BaFX (X represents a halogen element) as a carrier. This can be realized by utilizing the exhaust emission seen in the fluorescent carrier in which Eu 2+ is added.
Here, voluntary light emission means that after the temporary light emission of fluorescent light is finished, when it is excited again by irradiation with ultraviolet light or infrared light, all the stored energy becomes fluorescent light and emits light again. Refers to the phenomenon.
[0017]
If you use voluntary luminescence, fluorescent light is generated by irradiating UV light etc. when conducting a deterioration inspection of concrete structures. It will be very easy to inspect.
[0018]
Moreover, cracks on the surface of concrete do not necessarily occur only at the limit of the proof stress of the structure. For example, cracks may occur due to corrosion expansion of reinforcing bars due to salt in concrete. In this case, since cracks, that is, fluorescence occurs along the reinforcing bars arranged in the concrete, it is easy to estimate that the cause of deterioration is the corrosion expansion of the reinforcing bars. Therefore, the manager of the structure can accurately determine the time to suspend and repair the concrete by the fluorescence.
[0019]
In the said embodiment, although the fluorescent carrier was grind | pulverized into powder and the method of apply | coating such powder to the concrete surface was demonstrated, this invention is not limited to this.
[0020]
As another embodiment, for example, a fluorescent carrier is prepared in a particle size of about 0.5 mm, and further mixed with cement to form a mortar, whereby the mortar is applied to the concrete surface.
[0021]
Examples of the present invention will be described below.
[0022]
First, a fluorescent carrier powder was prepared as follows.
That is, the raw materials for the fluorescent carrier were No. 1 shown in Table 1. After weighing and mixing so as to have the composition of 1, the mixture was put in an alumina crucible, and the alumina crucible was put in a slightly larger alumina crucible filled with granular carbon and capped. This crucible is put in an electric furnace, heated from room temperature to 1800 ° C. over 3 hours, further kept at 1800 ° C. for 2 hours to melt the raw material, gradually cooled to 1600 ° C. over 2 hours, and then to room temperature Was allowed to cool in the furnace to obtain Sample 1.
The sample 1 was identified as hexagonal celsian, which is one of the crystal structures of feldspar, by measuring powder X-ray diffraction.
Further, the sample 1 was pulverized by a ball mill to obtain a fluorescent carrier 1.
[0023]
The following is an example in which fractoluminescence is applied to detect deterioration occurring in a concrete structure.
[0024]
Example 1
<Production of specimen>
Methylsiloxane was used as a coating material, and the fluorescent carrier 1 was mixed with a ball mill at a rate of 100 g / L. The mixture was applied to the side of a cylindrical (10 cmφ × 20 cm) concrete specimen using a brush.
<Tests and results>
When a compressive force was applied to the concrete specimen from above and below with a compression tester, fluorescence was observed on the surface of the concrete specimen when broken. By comparing the fracture surface of the high-speed photograph and the concrete specimen, it was found that the fluorescence was emitted in order from the position considered as the base point of the fracture.
[0025]
Example 2
<Production of specimen>
Fluorescent carrier 1 was mixed with acrylic paint at a rate of 200 g / L. An acrylic paint mixed with the fluorescent carrier 1 was sprayed onto the lower surface of a floor-plate concrete specimen of a plate-like bridge model (100 cm × 30 cm × 3 cm) prepared in advance.
<Tests and results>
When the floor concrete test specimen was loaded from the upper surface, fluorescence was generated at the center of the floor concrete test specimen, and cracks were generated at the center of the concrete specimen lower face in a direction perpendicular to the longitudinal direction of the floor board.
From the analysis of the strain gauge embedded in advance, the position where the fluorescence was visually confirmed coincided with the position of the crack.
[0026]
Example 3
<Production of specimen>
In order to conduct a fructoluminescence function experiment as an indicator of concrete deterioration due to salt damage, the same coating as in Example 2 was applied to one side of a concrete plate specimen with reinforcing bars.
<Tests and results>
The concrete plate-like specimen was placed in a salt damage promotion tester in which saturated saline was sprayed intermittently, and salt damage was caused to observe fluorescence.
Fluorescence was observed along the rebar, but eventually cracks appeared at that location. As a result of the inspection, it was confirmed that the reinforcing bars were expanded due to rust, that is, deterioration caused by cracks in the concrete surface due to typical salt damage.
[0027]
【The invention's effect】
According to the present invention, when the concrete structure reaches the limit of the proof stress, first, a fine crack runs on the surface of the concrete that cannot withstand the tensile stress. It can be easily detected as a rough surface.
In practice, for example, by applying a fluorescent carrier to the underside of a concrete girder bridge and observing the color change, the soundness of the bridge can be confirmed. It is effective as an alternative monitoring method.
Claims (3)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000025121A JP4229562B2 (en) | 2000-02-02 | 2000-02-02 | Deterioration detection method for concrete structures |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000025121A JP4229562B2 (en) | 2000-02-02 | 2000-02-02 | Deterioration detection method for concrete structures |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2001215195A JP2001215195A (en) | 2001-08-10 |
JP4229562B2 true JP4229562B2 (en) | 2009-02-25 |
Family
ID=18551024
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2000025121A Expired - Fee Related JP4229562B2 (en) | 2000-02-02 | 2000-02-02 | Deterioration detection method for concrete structures |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP4229562B2 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5712625B2 (en) * | 2011-01-17 | 2015-05-07 | Jfeスチール株式会社 | Anti-corrosion paint and painted steel |
CN105067508B (en) * | 2015-09-02 | 2019-03-01 | 无锡通用钢绳有限公司 | A kind of wirerope alkali resistance test equipment and method |
Family Cites Families (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5117149B2 (en) * | 1972-07-07 | 1976-05-31 | ||
JPS63204142A (en) * | 1987-02-19 | 1988-08-23 | Ishikawajima Harima Heavy Ind Co Ltd | Cracking inspection for concrete |
JPH01114740A (en) * | 1987-10-29 | 1989-05-08 | Mitsubishi Heavy Ind Ltd | Detection of crack of concrete |
JPH0238484A (en) * | 1988-07-27 | 1990-02-07 | Toshiba Corp | Inorganic light-emitting substance |
JPH03261863A (en) * | 1990-03-12 | 1991-11-21 | Nippon Kozai Kk | Method for measuring crack in concrete structure and measuring agent used therein |
JPH0812189B2 (en) * | 1990-11-21 | 1996-02-07 | 関西電力株式会社 | Degradation method for building materials |
JPH07117532B2 (en) * | 1992-09-25 | 1995-12-18 | 孝 西山 | Method to analyze the structure of bedrock, concrete, etc. |
JP3329029B2 (en) * | 1993-11-11 | 2002-09-30 | 株式会社大林組 | Intelligent structural members |
JP3199108B2 (en) * | 1995-11-20 | 2001-08-13 | 株式会社大林組 | Concrete member and its crack detection method |
JP2735159B2 (en) * | 1996-03-26 | 1998-04-02 | 工業技術院長 | Method for predicting breakage of brittle material structural members |
JPH1031002A (en) * | 1996-07-15 | 1998-02-03 | Arusu Kaihatsu Kk | Structure and method of detecting crack of structure |
JPH10111266A (en) * | 1996-10-03 | 1998-04-28 | Shimizu Corp | Inspection for concrete structure |
JP3785471B2 (en) * | 1997-11-20 | 2006-06-14 | 株式会社間組 | Method for determining concrete deterioration and reagent for determining concrete deterioration |
JP3136338B2 (en) * | 1997-11-28 | 2001-02-19 | 工業技術院長 | Light-emitting material, method for producing the same, and light-emitting method using the same |
JPH11183383A (en) * | 1997-12-18 | 1999-07-09 | Hazama Gumi Ltd | Fluorescence measuring method for concrete containing fluorescent colorant |
JP2001153788A (en) * | 1999-11-25 | 2001-06-08 | Hitachi Cable Ltd | Method for diagnosing deterioration of structure and fluorescent structure |
JP3356168B2 (en) * | 2001-02-07 | 2002-12-09 | 株式会社大林組 | Concrete material |
-
2000
- 2000-02-02 JP JP2000025121A patent/JP4229562B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JP2001215195A (en) | 2001-08-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Zhang et al. | Observation and quantification of water penetration into strain hardening cement-based composites (SHCC) with multiple cracks by means of neutron radiography | |
Singh et al. | Influence of cellulose fiber addition on self-healing and water permeability of concrete | |
Zhang et al. | Neutron imaging of water penetration into cracked steel reinforced concrete | |
Rosselló et al. | Fracture of model concrete: 2. Fracture energy and characteristic length | |
Vanniamparambil et al. | A data fusion approach for progressive damage quantification in reinforced concrete masonry walls | |
An et al. | Mechanical Properties of Weathered Feldspar Sandstone after Experiencing Dry‐Wet Cycles | |
Nahali et al. | Effect of Na3PO4 addition in mortar on steel reinforcement corrosion behavior in 3% NaCl solution | |
Mpalaskas et al. | Acoustic emission monitoring of granite under bending and shear loading | |
Timilsina et al. | A life-time reproducible mechano-luminescent paint for the visualization of crack propagation mechanisms in concrete structures | |
Duffó et al. | Application of gamma-ray radiography and gravimetric measurements after accelerated corrosion tests of steel embedded in mortar | |
Belayachi et al. | Thermally-induced cracks and their effects on natural and industrial geomaterials | |
He et al. | Durability evaluation of reinforced concrete with surface treatment of soy methyl ester-polystyrene under freeze-thaw cycles and calcium chloride | |
Yang | Assessing cumulative damage in concrete and quantifying its influence on life cycle performance modeling | |
Sassoni et al. | New method for controllable accelerated aging of marble: Use for testing of consolidants | |
JP4229562B2 (en) | Deterioration detection method for concrete structures | |
Verstrynge et al. | Debonding damage analysis in composite-masonry strengthening systems with polymer-and mortar-based matrix by means of the acoustic emission technique | |
Pazdera et al. | Nondestructive testing of advanced concrete structure during lifetime | |
Alhawat et al. | Evaluation of steel corrosion in concrete structures using impact-echo method | |
Santos et al. | In-situ techniques for mechanical performance and degradation analysis of rendering walls | |
Yang et al. | Interaction between micro-cracking, cracking, and reduced durability of concrete: Developing methods for considering cumulative damage in life-cycle modeling | |
Ferraro | Advanced nondestructive monitoring and evaluation of damage in concrete materials | |
Olawale | In-situ triboluminescent optical fiber sensor for real-time damage monitoring in cementitious composites | |
JP5655030B2 (en) | System and method for warning that a person is facing radioactive material | |
Benboudjema et al. | Experimental analysis of drying shrinkage cracking in coating mortars by digital image correlation | |
Clifton et al. | Nondestructive evaluation methods for quality acceptance of installed building materials |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
RD04 | Notification of resignation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7424 Effective date: 20040705 |
|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20060914 |
|
A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A711 Effective date: 20070119 |
|
A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20070119 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080402 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080425 |
|
A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080624 |
|
TRDD | Decision of grant or rejection written | ||
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20081121 |
|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20081202 |
|
R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111212 Year of fee payment: 3 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111212 Year of fee payment: 3 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121212 Year of fee payment: 4 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121212 Year of fee payment: 4 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20131212 Year of fee payment: 5 |
|
LAPS | Cancellation because of no payment of annual fees |