JP2011133359A - Deterioration diagnosis method of autoclaved lightweight concrete horizontal member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To conveniently, quickly and properly diagnose a deterioration level of an autoclaved lightweight concrete (ALC) horizontal member without removing the member and implementing a test. <P>SOLUTION: In the ALC horizontal member, a reaction calcium content (mass%) is measured by a chemical analysis, and a carbon dioxide gas content (mass%) is measured by a thermal analysis. The carbonation degree (%) obtained by a formula (the carbon dioxide gas content (mass%)-1)/(reaction calcium content (mass%)×44/56-1)×100 is calculated based on measurement results. The deterioration level is diagnosed based on the carbonation degree (%) in response to cases whether the horizontal member is a floor material or a roof material and whether there is a persistent load. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention is to confirm that the durability, which is the most important problem in actual use, is maintained for lightweight cellular concrete (ALC) panels used as horizontal members of the roof or floor of a building. The present invention relates to a deterioration diagnosis method for an ALC horizontal member.

  ALC is mainly composed of siliceous raw materials such as silica and calcareous raw materials such as cement and quick lime. After adding water and aluminum powder and other additives to these fine powders to form a slurry, the reaction of the aluminum powder Is produced by carrying out high-temperature and high-pressure steam curing with an autoclave after forming into a predetermined size by foaming, semi-curing by reaction of calcareous raw material. Such ALC is widely used as a building material because it is light in weight and has an absolute dryness specific gravity of about 0.5 and is excellent in fire resistance, heat insulation, and workability.

  An ALC panel using such an ALC can be used as a horizontal member in addition to a wall material. However, since the ALC has a lower strength than ordinary concrete, the ALC panel has a load load as a horizontal member. Used only for small roofs or floors with short spans.

  ALC is deteriorated by continuous use for many years. Building roofs and floors that use ALC panels must be safe because heavy objects and people are on them. Therefore, when an ALC panel is used as a horizontal member, it is required to accurately determine such deterioration and take appropriate countermeasures accordingly.

  However, these horizontal members are often hidden by finishing or the like, and it is difficult to visually confirm the deterioration. In addition, removing the ALC panel from the building and performing the strength test requires a lot of costs and labor. For this reason, there is a need for a method that can easily diagnose the deterioration level of the ALC panel as a horizontal member.

  The deterioration of the ALC horizontal member means that cracks occur, the panel strength decreases, and the deflection increases, which is the most important of these. Design specifications in the ALC panel structure design guidelines are also the most important. “Deflection” is defined as. The factors of these deterioration phenomena are roughly classified into external factors and internal factors. External factors include earthquakes, frame deformation, fatigue due to wind pressure or load, and fire. On the other hand, the internal factors include rebar rust due to carbonation, repeated drying shrinkage and wet expansion, frost damage, salt damage, and the like. Therefore, it can be said that it is necessary to comprehensively diagnose deterioration due to these factors.

  Among the causes of deterioration, carbonation is a reaction in which tobermorite, which is a main substance constituting ALC, decomposes into amorphous silicate (silica gel) and calcium carbonate in an environment where carbon dioxide gas and moisture exist. . It is known that such carbonation proceeds gradually even when finishing and other construction are appropriately performed. Carbonation causes ALC to shrink (carbonation shrinkage), and carbonized ALC has a higher drying shrinkage rate. Repeated drying shrinkage and wet swelling cause cracks, reduced panel strength, and deflection. Will lead to an increase.

  The inventor pays attention to such a carbonation degree, examines the relationship between ALC carbonation and durability, and discloses a method for diagnosing the durability of an ALC panel using the degree of carbonation of ALC as an index.

  For example, in Patent Document 1, the total calcium oxide content (mass%) and carbon dioxide gas content (mass%) of ALC are measured, and (carbon dioxide gas content × 56/44) / (total calcium oxide content) × The ALC panel having a carbonation degree (%) obtained by the formula of 100 of 50% or more discloses a durability diagnostic method for diagnosing that the durability has deteriorated.

  Further, for example, in Patent Document 2, the calcium carbonate equivalent amount C (mass%) of calcium carbonate obtained by quantitatively measuring the calcium carbonate content by thermal analysis and the total calcium content are quantitatively measured by chemical analysis. Calcium oxide equivalent amount Cmax (mass%) of total calcium, calcium sulfate equivalent amount Cs (mass%) of calcium sulfate obtained by quantitatively measuring the total sulfur content, and unproduced by the same production method as the test sample With respect to the carbonated sample, a calcium oxide equivalent amount C0 (mass%) of calcium carbonate obtained by quantitatively measuring the calcium carbonate content by a thermal analysis method was obtained, and (C−C0) / (Cmax−Cs−C0) × A degradation degree quantitative evaluation method is disclosed in which the degradation degree of the test sample is quantitatively evaluated based on the carbonation degree Dc2 (%) of the equation of 100.

  However, any of these deterioration diagnosis methods is applied to the deterioration diagnosis of the ALC wall material, and cannot be applied to the deterioration diagnosis of the ALC horizontal member having different required performance.

  In addition, the process of carbonation varies greatly depending on the environment in which the ALC product is placed, etc., and there are situations where it is necessary to judge the degradation considering such effects. obtain.

JP 2000-180437 A JP 2000-193658 A

Supervised by the Institute for Architectural Institutions, “ALC Panel Structural Design Guidelines and Explanation”, ALC Association, 2004

  An object of the present invention is to provide a method that can easily, quickly, and accurately diagnose the deterioration level of an ALC horizontal member.

  The method for diagnosing deterioration of a lightweight aerated concrete (ALC) horizontal member according to the present invention is a reaction calcium content (mass%) by chemical analysis and a carbon dioxide gas content (mass%) by thermal analysis for the ALC horizontal member to be diagnosed. , And based on the measurement result, the carbonation degree obtained by the formula of (carbon dioxide content (mass%)-1) / (reacted calcium content (mass%) × 44 / 56-1) × 100 (%) Is calculated, and the horizontal member is a flooring material or a roofing material, and whether there is a continuous load or not. Diagnose the level.

  Specifically, the total calcium content (mass%) and the sulfur trioxide content (mass%) were measured by the chemical analysis for the sample of the ALC horizontal member to be diagnosed, and the total calcium content (mass%) %)-Sulfur trioxide content (mass%) × reaction calcium content (mass%) obtained by the formula of 56/80 and calculating the amount of mass decrease at 600 ° C. to 850 ° C. by thermal analysis of the sample. The carbon dioxide content (% by mass) is measured, and the carbonation degree (%) is calculated by the above formula.

  In order to enable this, in the present invention, for a plurality of lightweight aerated concrete horizontal members, the reaction calcium content (mass%) by chemical analysis and the carbon dioxide gas content (mass%) by thermal analysis are measured in advance. Based on the measurement results, the degree of carbonation (%) obtained by the formula of (carbon dioxide content (mass%)-1) / (reacted calcium content (mass%) × 44 / 56-1) × 100 is calculated. In addition, the design load deflection and the long-term deflection data of each of the plurality of lightweight cellular concrete horizontal members are obtained, and the numerical value of the design load deflection or the long-term deflection is the initial deflection limit of the flooring material or the roofing material. Alternatively, the degree of carbonation (%) of the lightweight cellular concrete horizontal member when it falls under the deflection limit during long-term loading is obtained.

  Then, the degree of carbonation (%) of the light-weight aerated concrete horizontal member to be diagnosed obtained as described above is calculated based on (1) the continuous load on the floor material. (2) Floor material by comparing with the degree of carbonation when the previously obtained value of deflection under long-term load corresponds to the initial deflection limit of the floor material or the deflection limit under long-term load. In the case where there is no continuous load, the numerical value of the design load deflection obtained in advance is compared with the degree of carbonation when the initial deflection limit of the flooring material or the deflection limit at the time of long-term load is satisfied. 3) When there is a continuous load on the roofing material, the previously obtained numerical value of deflection under long-term load is compared with the degree of carbonation when the initial deflection limit of the roofing material or the deflection limit under long-term load is met. To do (4) When there is no continuous load on the roofing material, the carbonation degree when the numerical value of the design load deflection obtained in advance corresponds to the initial deflection limit of the roofing material or the deflection limit under long-term loading. The deterioration level is determined by comparing with.

  Preferably, when the degree of carbonation (%) of the lightweight cellular concrete horizontal member to be diagnosed corresponds to the initial deflection limit of the flooring material or roofing material, the value of the design load deflection or the deflection under a long-term load corresponds to the initial deflection limit. When the value is below “degree” and “sound”, the numerical value exceeds the carbonation degree when it falls under the initial deflection limit of the flooring or roofing material, and falls under the long-term deflection limit of the flooring or roofing material If the value is below the carbonation degree of the product, “Caution: Repair is required” and the value exceeds the carbonation degree when the value falls under the deflection limit under long-term load of flooring or roofing material. It is determined that it is necessary.

  More specifically, the deflection curve of the initial deflection (design load deflection = elastic deflection) shown in FIG. 1, in particular, the intersection of the curve with the initial deflection limit (L / 400 or L250) of the flooring or roofing material and Correlation between the intersection with the long-term deflection limit (L / 250 or L / 156) and the degree of carbonation of the ALC horizontal member, or the deflection curve of long-term deflection (elastic deflection + creep deflection), Based on the correlation between the curve and the above intersection and the carbonation degree of the ALC horizontal member, the lightweight cellular concrete horizontal member to be diagnosed is (1) when there is a continuous load on the flooring, When the obtained carbonation degree is 27% or less, “sound”, when it exceeds 27% and 39% or less, “caution: need repair”, and when it exceeds 39%, “deterioration: reinforcement or Diagnose as `` replacement required '' , (2) When there is no continuous load on the flooring material, “healthy” when the obtained carbonation degree is 35% or less, and “cautions” when it is over 35% and 48% or less. : If repair is necessary ”, if it exceeds 48%, it is diagnosed that“ deterioration / reinforcement or replacement is necessary ”. (3) If there is a continuous load on the roofing material, the obtained carbonation degree is 38 Diagnose as “healthy” when the percentage is below 50%, “attention required: repair required” when above 50% and below 38%, and “deterioration / reinforcement or replacement required” above 50%, (4) When there is no continuous load on the roofing material, the above obtained degree of carbonation (%) is “sound” when it is 48% or less, and when it is over 48% and 60% or less, “cautions: If it exceeds 60%, it is diagnosed as “deterioration / reinforcement or replacement required”.

  However, the diagnostic criteria for flooring will be applied to walking roofs and roofs in snowy areas.

  The diagnosis method of the present invention makes it possible to easily, quickly and accurately diagnose the deterioration level of lightweight cellular concrete horizontal members that are difficult to remove and test and difficult to judge from the surface. .

FIG. 1 shows the relationship between the degree of carbonation (%), elastic deflection, and elastic deflection + creep deflection for an ALC panel.

  The method for diagnosing deterioration of a lightweight cellular concrete (ALC) horizontal member of the present invention includes the following [1] to [5].

  [1] A sample is obtained by performing cored sampling of the ALC horizontal member.

  Core removal can be performed using a known core drill or the like. At this time, if possible, a sample is taken as thick as possible in the thickness direction of the ALC horizontal member, and after stratified in the thickness direction, the following analysis is performed for each part. Preferably it is done. This is to obtain an average characteristic value in the thickness direction of the ALC panel because a part of these samples are used for the chemical analysis and thermal analysis samples described later. The number of layers is arbitrary depending on the thickness of the ALC horizontal member, but in the case of an ALC panel used as a horizontal member (standard thickness is 100 to 150 mm), preferably about 3 to 5 layers, the degree of carbonation The average value of the panel can be accurately obtained for the characteristics including.

  [2] The total calcium content (mass%)-sulfur trioxide content (mass%) was measured by chemical analysis of the sample to measure the total calcium content (mass%) and sulfur trioxide content (mass%). While calculating the reaction calcium content (mass%) obtained by the formula of x56 / 80, the carbon dioxide content (mass%) which is the mass reduction | decrease in 600 to 850 degreeC by the thermal analysis of this sample was measured. Then, the degree of carbonation (%) obtained by the formula of (carbon dioxide content (mass%)-1) / (reacted calcium content (mass%) × 44 / 56-1) × 100 is calculated.

  The chemical analysis can employ a known method as long as it can quantitatively measure calcium and sulfur trioxide. Examples of those capable of accurately quantitatively measuring calcium and sulfur trioxide include a fluorescent X-ray analysis method and an ICP method.

  The reactive calcium content is the total calcium content in the sample minus the calcium content present as calcium sulfate that does not contribute to the production and reaction of tobermorite.

  The thermal analysis uses a thermogravimetric analysis measuring device that shows the mass loss due to the decomposition of calcium carbonate. In particular, in order to clarify the decomposition of calcium carbonate, a thermogravimetric-differential thermal analyzer (TG-DTA) is used. It is preferable to use and measure.

  Some calcium carbonates have different crystal structures, but they all decompose into calcium oxide and carbon dioxide at 600 ° C to 850 ° C, so the carbon dioxide content (% by mass) is accurately measured quantitatively by thermal analysis. It is possible to do.

  “1” in the calculation formula of carbonation degree (%) (carbon dioxide content (mass%)-1) / (reacted calcium content (mass%) × 44 / 56-1) × 100 is uncarbonated sample Is a representative value of the carbon dioxide content (% by mass) in FIG. 1, and corresponds to “C0” in the calculation formula (C−C0) / (Cmax−Cs−C0) × 100 of the carbonation degree (%) of Patent Document 2 To do. In the deterioration diagnosis of the horizontal member, since the ALC panel that has already deteriorated is targeted, the carbon dioxide content (% by mass) when the panel is not carbonated cannot be known. Here, the calculation formula for the degree of carbonation (%) in Patent Document 1 (carbon dioxide content (mass%) × 56/44) / (total calcium oxide content (mass%)) × 100 It can be considered that the carbon dioxide content (mass%) at the time of carbonation is ignored, but in this case, the carbon dioxide content (mass%) at the time of non-carbonation is calculated and ignored. The error is about 2 to 5% in terms of carbonation degree (%), which may affect the evaluation result of the deterioration diagnosis.

  The present inventor has sampled and evaluated the carbon dioxide content (mass%) at the time of non-carbonation from many types of panels, and as a result, in almost all cases, 0.8 mass% to 1.2 mass%. I found out. Therefore, if the carbon dioxide gas content at the time of non-carbonation is calculated as a constant value of 1.0% by mass, the error in the degree of carbonation (%) is less than 1%, and there is almost no influence on the evaluation result of the deterioration diagnosis. . As a result of these studies, the calculation formula for the degree of carbonation (%) in the method for diagnosing deterioration of the lightweight cellular concrete horizontal member of the present invention is (carbon dioxide content (mass%)-1) / (reacted calcium content ( Mass%) × 44 / 56-1) × 100.

  [3] It is confirmed whether or not there is a continuous load for each ALC horizontal member subject to deterioration diagnosis.

  Sustained load means a sustained load caused by a heavy object such as a piano or chiffon being placed in one place for a long period of time in a living room, for example, temporary loads such as traffic of humans and light vehicles. Non-sustained loads due to long-term repetition of the are eliminated.

  That is, for the flooring material and the roofing material, determination criteria to be described later are set depending on whether there is a continuous load or not. The reason for this is that if the judgment is made under the condition that the continuous load is ignored, the deflection limit may be exceeded even though it is continuously used with the load within the design load of the ALC panel. When it is used only in a situation where there is no sustained load, if the judgment is made under a condition with a sustained load, it may require treatment for deterioration even though the service limit has not been reached. This is because there is a possibility of economic problems.

  [4] Depending on whether each ALC horizontal member subject to deterioration diagnosis is flooring or roofing and whether there is a continuous load, the carbonation degree (%) Based on this, the deterioration level of the ALC horizontal member is diagnosed.

  Degradation level evaluation index is the initial (design load) when removing the ALC horizontal member without actually damaging it and applying a load of (1 ± 0.02) design load by quadrant 2-line loading It is possible to use a deflection (elastic deflection) and a deflection under a long-term load (elastic deflection + creep deflection) generated when the load is continued for one year or more.

  In the ALC structural design standard (see Non-Patent Document 1), the limit deflection when a design load is applied in the span L is defined as L / 400 for the floor and L / 250 for the roof. In addition, according to Ministry of Construction Notification No. 1459 (May 31, 2000), deformation increases due to a long-term load depending on the type of structure against the maximum deflection of building beams or floor slabs. An adjustment coefficient (referred to as a deformation increase coefficient) is defined. According to this, the deformation increase coefficient of the structure using the ALC panel including the ALC flooring is 1.6. This is because the initial deflection limit is set in advance to a high performance of L / 400 in consideration of the creep deflection so that the deflection of the flooring material is kept below L / 250 (long-term deflection limit) after a long-term load. (L / 400 × 1.6 = L / 250).

  The deformation increase coefficient of the roofing material is not particularly defined, but if the concept of flooring is applied in the same manner, the deflection limit at the time of long-term load can be defined as L / 250 × 1.6 = L / 156. However, for roofing materials used for walking roofs and roofs in heavy snow areas, it is supposed to comply with the prescribed values for flooring.

From the above, the deflection limit of ALC flooring and roofing considering the deformation increase factor is divided into initial and long-term load,
・ Floor: Initial L / 400, long-term load L / 250,
-Roof: Initial L / 250, long-term load L / 156,
Can be defined.

Since this deflection limit is considered to be a limit of the performance that an actual horizontal member should have, it is appropriate to use this value as a criterion for deterioration diagnosis. That is, as described below, basically, the design load deflection (elastic deflection) of the ALC panel to be diagnosed is
・ If within initial deflection limit: Healthy,
・ If the initial deflection limit is exceeded and within the deflection limit under long-term load: Caution is required, that is, repair is required.
・ If the deflection limit is exceeded during long-term load: Deterioration, ie, reinforcement or replacement is required.
And set the criteria.

  Specifically, in the case of flooring, the deflection rate considered healthy is 1/400 or less, caution: The deflection rate required for repair exceeds 1/400 and is 1/250 or less. Deterioration: Reinforcement or replacement required The deflection rate assumed is more than 1/250. On the other hand, in the case of a roof material, it becomes 1/250 or less and exceeds 1/250, respectively, and becomes 1/156 or less, and exceeds 1/156.

  However, as described above, for each of the flooring material and the roofing material, it is necessary to consider each case when there is a continuous load and when there is no continuous load. That is, the criterion using the design load deflection is applied when there is no continuous load.

  On the other hand, since it is necessary to consider the creep deflection in order to consider the sustained load, the ALC panel that is the subject of the diagnosis that has been subjected to the sustained load has a long-term deflection (elastic deflection + creep deflection). ), The same criteria as described above are applied.

  For each of a plurality of flooring materials and roofing materials in which various degrees of carbonation (%) are measured, the cases are classified into cases where there is a continuous load and cases where there is no continuous load. As a result, the level of deterioration based on the deflection limit of the target ALC horizontal member was determined based on the measured degree of carbonation as follows: Thus, the knowledge that it can be evaluated is obtained.

  That is, when there is a continuous load on the flooring material, when the carbonation degree is 27% or less, the deterioration level according to the above criteria corresponds to “sound”, and the carbonation degree exceeds 27% and is 39% or less. In this case, the deterioration level corresponds to “Caution required: repair required”, and when the carbonation degree exceeds 39%, the deterioration level corresponds to “deterioration: reinforcement or replacement required”.

  When there is no continuous load on the flooring, the case where the carbonation degree is 35% or less is also “sound”, and the case where the carbonation degree is more than 35% and 48% or less is “Caution: Repair required”. In addition, the case where the carbonation degree exceeds 48% corresponds to “deterioration: reinforcement or replacement required”, respectively.

  When there is a continuous load on the roofing material, the case where the carbonation degree is 38% or less is also “sound”, and the case where the carbonation degree is more than 38% and 50% or less is “Caution: Needs repair.” In addition, the case where the carbonation degree exceeds 50% corresponds to “deterioration: reinforcement or replacement required”, respectively.

  When there is no continuous load on the roofing material, the case where the carbonation degree is 48% or less is also “sound”, and the case where the carbonation degree is more than 48% and less than 60% is “Caution: Repair is required”. In addition, the case where the carbonation degree exceeds 60% corresponds to “deterioration: reinforcement or replacement required”, respectively.

  In actual operation, the degree of carbonation (%) obtained by measuring the sample obtained from the ALC horizontal member to be diagnosed is used as a diagnostic criterion, and the case with or without a sustained load is divided into cases. Thus, the deterioration level in accordance with the above determination criterion is determined. Therefore, it is possible to make a detailed diagnosis about the degree of deterioration of the ALC horizontal member without removing the ALC panel.

  However, as described above, the diagnostic criteria for flooring is applied to roofing materials used for walking roofs and roofs in snowy areas.

  The deterioration diagnosis method of the present invention is not limited to the examples shown below.

  With regard to multiple ALC panels that were actually used as flooring and roofing materials in our own factories and company housing buildings, where the usage history is clear over a long period of time, each used years, parts used, finishing, The state of sustained load was investigated. Excessive load may have been removed from the sample due to the possibility of excessive deflection already in the pre-evaluation stage, so as not to damage the ALC panel that did not have sustained load. Carefully removed from the building.

  Examine the dimensions (thickness, width, length) of the removed ALC panel, cut out the short edge of the ALC panel partially, check the diameter and number of reinforcing bars inside, and design the ALC panel The load was determined.

  For each of the ALC panels, the design load deflection data was obtained by applying a load of 1 times the design load by quadrant 2-line loading and measuring the deflection change (elastic deflection) before and after the load. . The deflection was measured at the center of the span when loaded.

  After that, when the load was applied for about one year for each of the ALC panels, the increase in deflection was almost completed after 300 days had elapsed, and the deflection at the time point after continuing for one year was measured. By measuring the change (elastic deflection + creep deflection), deflection data under long-term loading was obtained.

  On the other hand, along with the indexing of the design load, each of the removed ALC panels is equally divided into five in the thickness direction, and core sampling is performed from one side of the ALC panel by penetrating in the thickness direction using a core drill. 5 samples for each area were obtained for each ALC panel, the degree of carbonation (%) was examined for each sample obtained, and the average value of the degree of carbonation (%) of each sample was calculated. Degree (%).

In addition, as a chemical analysis of the sample, the total calcium (Ca) content (mass%) and the sulfur trioxide (SO ₃ ) content of the sample using a fluorescent X-ray analyzer (Spectris Co., Ltd., PANalytical, Venus 200). (Mass%) was measured. From the measurement results, the reaction calcium content (mass%) obtained by the formula of total calcium content (mass%) − sulfur trioxide content (mass%) × 56/80 was calculated.

  Moreover, as a thermal analysis of a sample, carbon dioxide gas which is a mass reduction amount of each sample at 600 ° C. to 850 ° C. using a thermogravimetric-differential thermal analyzer (TG-DTA, manufactured by Mac Science Co., Ltd., TG-DTA2010SA). Content (mass%) was measured.

  From the measurement results of chemical analysis and thermal analysis, the degree of carbonation obtained by the formula of (carbon dioxide content (mass%)-1) / (reacted calcium content (mass%) × 44 / 56-1) × 100 ( %) Was calculated for each ALC panel.

  In addition, about the new ALC panel produced with the same manufacturing method, the thermal analysis was performed similarly and the carbon dioxide content (mass%) in an uncarbonated sample was measured, and it was 0.9 mass%. . Thereby, it was confirmed that the influence on the evaluation result of the carbon dioxide content at the time of non-carbonation can be removed by the above formula.

  FIG. 1 shows the relationship between the degree of carbonation (%), elastic deflection, and elastic deflection + creep deflection for each ALC panel. FIG. 1 shows the respective deflection limits (floor: initial L / 400, long-term load L / 250, roof: initial L / 250, long-term load L / 156) of the flooring material and the roofing material. In addition, since the special difference was not recognized by the plot of the graph by the flooring material and the roofing material, the data of both members are shown with the same plot. From a plot of each data according to the degree of carbonation, a data curve of deflection under long-term load (elastic deflection + creep deflection) and a data curve of initial deflection (elastic deflection) were obtained.

  Based on FIG. 1, for each of the flooring material and the roofing material, the evaluation criteria were obtained as follows for two cases, when there was a continuous load and when there was no continuous load.

  The degree of carbonation (%) at the intersection of the elastic deflection + creep deflection data curve and the initial deflection limit (L / 400) of the flooring material, and the long-term deflection limit (L / 250) of the flooring material is sustained. As a diagnostic standard for flooring under heavy load, when the carbonation degree is 27% or less, the deterioration level is “sound”, and when the carbonation degree is over 27% and 39% or less, the deterioration level is When “Caution required: repair required” and the carbonation degree exceeded 39%, the deterioration level was set as “Deterioration: Reinforcement or replacement required”, respectively.

  Similarly, the degree of carbonation (%) at the intersection of the elastic deflection data curve and the deflection limit of the flooring (initial L / 400, long-term load L / 250) is shown for the flooring when there is no continuous load. When the carbonation degree is 35% or less, the deterioration level is “sound”, and when the carbonation degree is over 35% and 48% or less, the deterioration level is “Caution: Needs repair.” When the degree of conversion exceeded 48%, the degradation level was set as “degradation: reinforcement or replacement required”, respectively.

  For roofing materials, the degree of carbonation (%) at the intersection of the elastic deflection + creep deflection data curve and the roofing material deflection limit (initial L / 250, long-term load L / 156) When the carbonation degree is 38% or less, the deterioration level is “sound”, and when the carbonation degree is over 38% and 50% or less, the deterioration level is “Caution: When the degree of carbonation exceeds 50%, the deterioration level was set as “Deterioration: Reinforcement or replacement required”.

  In addition, the degree of carbonation (%) at the intersection of the elastic deflection data curve and the deflection limit of the roofing material (initial L / 250, L / 156 during long-term loading) When the carbonation degree is 48% or less, the deterioration level is “sound”, and when the carbonation degree is over 48% and 60% or less, the deterioration level is “Caution: Needs repair” When the degree of conversion (%) exceeded 60%, the deterioration level was set as “deterioration: reinforcement or replacement required”, respectively.

  As described above, based on the above diagnostic criteria of the present invention, the deterioration diagnosis for flooring and roofing materials using the ALC panel that has actually deteriorated over time is performed, the ALC panel is removed, or a long-term panel loading test is performed. It was confirmed that it can be carried out simply, quickly and accurately only by taking a small core-free sample and measuring the degree of carbonation.

Claims (4)

For a plurality of lightweight aerated concrete horizontal members, the reaction calcium content (mass%) by chemical analysis and the carbon dioxide gas content (mass%) by thermal analysis are measured in advance. (Carbon mass) -1) / (reaction calcium content (mass%) × 44 / 56-1) × 100 The carbonation degree (%) obtained by the formula is calculated, and the plurality of lightweight cellular concrete horizontal members When the design load deflection and long-term deflection data are obtained, and the design load deflection or long-term deflection value corresponds to the initial deflection limit or the long-term deflection limit of the flooring or roofing material. Obtain the degree of carbonation (%) of the lightweight cellular concrete horizontal member,
Obtain the degree of carbonation (%) of the lightweight cellular concrete horizontal member to be diagnosed based on the measurement results of the chemical analysis and thermal analysis,
When the light-weight cellular concrete horizontal member to be diagnosed is (1) the floor material has a continuous load, the numerical value of the deflection at the time of long-term load obtained in advance is By comparing with the degree of carbonation in the case where the initial deflection limit of the material or the deflection limit at the time of long-term load is met, (2) When there is no continuous load on the flooring material, By comparing the degree of carbonation when the numerical value corresponds to the initial deflection limit of the flooring or the deflection limit at the time of long-term loading, (3) when there is a continuous load on the roofing material, the above-mentioned was obtained in advance. By comparing with the degree of carbonation when the value of deflection under long-term load corresponds to the initial deflection limit of roofing material or the deflection limit under long-term loading, (4) When there is no continuous load in the roofing material, The pre-obtained design load Numbers are, by comparing the carbonation of the case corresponding to the limit deflection during initial deflection limit or long loads roofing, determines deterioration level, the deterioration diagnosis method of a lightweight cellular concrete horizontal member.   The degree of carbonation (%) of the lightweight cellular concrete horizontal member to be diagnosed is equal to or less than the degree of carbonation when the numerical value of the deflection under the design load or the long-term load corresponds to the initial deflection limit of the flooring material or the roofing material. "Sound", the carbonation when the numerical value exceeds the carbonation degree when it falls under the initial deflection limit of the flooring or roofing material and falls under the long-term deflection limit of the flooring or roofing material If the value falls below the degree, “Caution: Repair is required” and if the numerical value exceeds the carbonation degree when it falls under the deflection limit under long-term load of flooring or roofing, “Deterioration: Reinforcement or replacement required” The method for diagnosing deterioration of a lightweight lightweight concrete horizontal member according to claim 1, wherein the determination is performed.   If the lightweight cellular concrete horizontal member to be diagnosed is (1) when the floor material has a continuous load, when the obtained carbonation degree is 27% or less, “healthy” and 27% If it exceeds 39%, it is diagnosed as “Caution: Repair required”, and if it exceeds 39%, it is diagnosed as “Deterioration: Reinforcement or replacement required.” (2) If there is no continuous load on the flooring, When the obtained carbonation degree is 35% or less, it is “sound”, when it exceeds 35% and is 48% or less, “attention required: repair is necessary”, and when it exceeds 48%, “deterioration / reinforcement or (3) When there is a continuous load on the roofing material, when the obtained carbonation degree is 38% or less, it is “sound” and exceeds 38% and 50% or less If it exceeds 50%, “Decrease / reinforcement or replacement” is required. (4) When there is no continuous load on the roofing material, the obtained carbonation degree (%) is “sound” when it is 48% or less, and when it is over 48% and 60% or less. 3. A method for diagnosing deterioration of a lightweight cellular concrete horizontal member according to claim 1 or 2, wherein if it exceeds 60%, it is diagnosed that "deterioration / reinforcement or replacement is required".   When the light-weight basic concrete horizontal member to be diagnosed is used as a roofing material for a walking roof or a roof in a snowy area, the diagnostic criteria for the flooring is applied. Deterioration diagnosis method for lightweight cellular concrete horizontal member as described in 1.

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