阅读说明：本技术 一种古建筑修复用块状生石灰掺杂粉化石灰灰浆及制备方法 (Blocky quicklime doped pulverized lime mortar for historic building restoration and preparation method thereof ) 是由 张典 王辉 尚国华 王菊琳 陈绍华 于 2021-06-23 设计创作，主要内容包括：一种古建筑修复用块状生石灰掺杂粉化石灰灰浆及制备方法,属于古建筑修补材料研究技术领域。其原材料组成包括胶结材料和水,其中胶结材料为块状生石灰和粉化石灰；块状生石灰为使用前呈块状存在的部分,粉化石灰为块状生石灰在空气中变质而形成的粉化部分。块状生石灰在胶结材料中质量百分比含量为50-70％,优选60％；优选出粉化石灰在胶结材料中质量百分比含量为30-50％,优选40％。本发明最大限度使用粉化变质石灰,同时使所制灰浆具有良好的力学性能、耐水性及耐冻融性。(A blocky quicklime doped pulverized lime mortar for historic building restoration and a preparation method thereof belong to the technical field of the research of historic building restoration materials. The raw material composition comprises a cementing material and water, wherein the cementing material is massive quicklime and powdered lime; the blocky quicklime is a blocky part before use, and the powdered lime is a powdered part formed by the metamorphic change of the blocky quicklime in the air. The mass percentage content of the massive quicklime in the cementing material is 50-70%, preferably 60%; preferably, the content of powdered lime in the cementitious material is 30-50% by mass, preferably 40%. The invention uses the pulverized deteriorated lime to the maximum extent, and simultaneously, the prepared mortar has good mechanical property, water resistance and freeze-thaw resistance.)

1. The blocky quicklime doped pulverized lime mortar for historic building restoration is characterized by comprising a cementing material and water, wherein the cementing material is blocky quicklime and pulverized lime; the blocky quicklime is a blocky part before use, and the powdered lime is a powdered part formed by the metamorphic change of the blocky quicklime in the air;

the mass percentage content of the massive quicklime in the cementing material is 50-70%, and the mass percentage content of the powdered lime in the cementing material is 30-50%.

2. The blocky quicklime doped chalked lime mortar for historic building restoration according to claim 1, wherein the blocky quicklime is 60% by weight of the cementitious material; the content of the powdered lime in the cementing material is 40 percent by mass.

3. The method as claimed in claim 1, wherein the lump quicklime doped with powdered lime mortar for renovating ancient architecture is lime having an apparent form of lump before use or a calcium oxide content of not less than 98%, and the powdered lime is lime having an apparent form of powder and being left in the air for not more than 3 months or a calcium carbonate content of not more than 18%.

4. The method for preparing a blocky quicklime doped chalked lime mortar for historic building restoration according to claim 1, which is characterized by comprising the following steps:

(1) sieving, separating blocky quicklime and powdered lime, spraying deionized water on blocky quicklime for a few times to slake the blocky quicklime into dry powder, and sieving to obtain splashed lime;

(2) weighing splashing lime and powdered lime according to the mass percentage of the cementing material, putting the splashing lime and the powdered lime into a container, mixing, adding water into the container according to the water-glue ratio of the smoldering lime, mixing until the lime reaches a completely wet powder state, and then sealing and placing for smoldering for at least 7 days;

(3) and after the lime slaking is finished, weighing the slaked wet lime powder, putting the slaked wet lime powder into a mortar stirrer container, adding water into the container according to the water-to-glue ratio in the sample preparation process, starting the stirrer, slowly stirring (140 revolutions per minute) for one minute, quickly stirring (285 revolutions per minute) for half a minute, and circulating for three times to obtain the newly-prepared white mortar which is uniformly stirred.

5. The method according to claim 4, wherein the water-to-gel ratio in the step (2) of the ashing process is preferably 0.5 to 1, more preferably 0.6; the water-to-gel ratio in the sample preparation process in the step (3) is preferably 0.02-0.1, and more preferably 0.05.

6. The method as claimed in claim 4, wherein the lump quicklime is sprayed to the lime in a small amount for several times to ensure a dry powder state, the water-cement ratio is controlled by the dry powder state, and the lump quicklime is sieved by a mesh<0.3cm²The ash is strictly added into the sieve according to the water-cement ratio, the mixture is uniformly mixed after water is added, the lime is completely wet, the lime is stored in a closed manner and is prevented from contacting air to avoid water evaporation, and the closed storage time is not less than 7 days.

7. The method as claimed in claim 4, wherein the step (1) of sieving, when separating the lump quicklime and the powdered lime, uses a mesh for sieving<0.3cm²The sieve of (1).

8. Use of the mortar according to claim 1, wherein the mortar is cured for 72 hours in room at normal temperature and humidity after being put into a mold, and then the mold is removed, and the demolded sample is left in room at normal temperature and humidity for further curing for 60 days.

Technical Field

The invention relates to an optimal proportion of blocky quicklime doped powdered lime mortar for repairing ancient buildings and a preparation method thereof, belonging to the technical field of research of ancient building repairing materials.

Background

The use of the traditional lime has a long history, the existing archaeological demonstration at present shows that the lime is fired and used in China at the earliest in the prehistoric period, the traditional lime is used as a structural adhesive for most of the existing ancient buildings, and thousands of ancient buildings are left in the clearness period only, so that the lime is an excellent building heritage in China. However, cultural relics such as ancient buildings, city walls and the like using the traditional mortar as a binder are mostly seriously damaged after thousands of years of wind, rain, sunshine and artificial damage, and reasonable repair and reinforcement are urgently needed due to the fact that some cultural relics are endangered to be damaged. People in the last century generally repair ancient buildings by cement mortar with high hardening speed and high mechanical strength, the adjacent structure is quickly damaged by large mechanical stress introduced by cement, the ancient buildings are gradually known in the ancient building repair, the destructive repair is not allowed in the ancient building repair, and in order to avoid the above situation, the domestic ancient building repair material is widely used by traditional lime with better adaptability.

The traditional limestone is blocky quicklime after being fired, water is needed to be used for splashing the lime before the lime is used, so that the blocky lime is dispersed into powder, and the lime is used as a building cementing material after being fully cured. After the slaked lime is slurried with water, the slurry is gradually carbonated in the air, and then the plastic slurry is developed into a stone body with higher strength, and the strength of the stone body meets the performance requirements of the building cementing material.

The quicklime has strong water absorption, the blocky quicklime cannot be prevented from contacting with air in the storage process, part of blocky quicklime contacting with the air can absorb moisture in the air to carry out slaking reaction to become powder, part of powder lime further reacts with water and carbon dioxide in the air to be gradually carbonized, mortar prepared from the completely carbonized powder lime cannot continuously absorb the carbon dioxide in the air to continuously harden and develop strength along with the lapse of time, and the characteristics of a cementing material are not met. As a large amount of lime is purchased in advance for standby in actual engineering, the pulverization speed of a large amount of blocky raw lime is still high even if the blocky raw lime is stacked in a closed manner, and a large amount of powdered lime which is carbonized and does not accord with the characteristics of a cementing material is not lacked. If the method of using blocky quick lime is still adopted, the powdered lime can cause potential safety hazard when being used for ancient buildings. And the hydrated lime powder with good performance exists in a large amount of powdery lime, and the forming process is similar to the preparation of splashing lime. If the waste is totally discarded, the waste is serious. Therefore, the application starts from the factor, and invents a using method of mixing the blocky quick lime with the powdered lime so as to use the powdered modified lime to the maximum extent and simultaneously enable the prepared mortar to have good mechanical property, water resistance and freeze-thaw resistance.

Disclosure of Invention

The invention aims to solve the potential safety hazard problem caused by using a part of pulverized blocky quick lime as an ancient building repair material and eliminate the problem of resource waste, and develops an optimal proportion and a preparation method of the part of pulverized blocky quick lime doped with the blocky quick lime so as to solve the problem of resource waste while not reducing the performance. At present, the ancient architecture is repaired on a large scale only by using traditional raw materials, further damage to structures is avoided, a large amount of lime can be pulverized and deteriorated when placed on site, the risk of performance reduction is caused when the lime is directly used, and the waste is caused when the lime is completely abandoned.

In order to achieve the purpose, the mortar doped with the powdered lime with excellent performance is obtained, and the raw materials of the mortar comprise cementing materials and water, wherein the cementing materials are massive quicklime and powdered lime; the blocky quicklime is a blocky part before use, the powdered lime is a powdered part formed by the metamorphic change of the blocky quicklime in the air, and the blocky quicklime and the powdered lime are mixed together before proportioning.

Preferably, the content of the splashed lime prepared from the blocky quicklime in the cementing material is 50-70% by mass, and further preferably 60%; the content of the pulverized lime in the cementing material is preferably 30-50% by weight, and more preferably 40%.

Wherein, the adopted blocky quicklime is lime with blocky appearance or calcium oxide content not less than 98 percent before use, and the pulverized lime is lime with powdery appearance and lime or calcium carbonate content not more than 18 percent after being placed in the air for not more than 3 months;

the method comprises the following steps:

(1) sieving (preferably with a mesh<0.3cm²) Separating lump quicklime and powdered lime, spraying deionized water on the lump quicklime for several times to cure it to dryPowdering, sieving (mesh)<0.3cm²) Obtaining splashing ash;

(2) weighing splashing lime and powdered lime according to the mass percentage of the cementing material, putting the splashing lime and the powdered lime into a container, mixing, adding water into the container according to the water-glue ratio of the smoldering lime, mixing until the lime reaches a completely wet powder state, and then sealing and placing for smoldering for at least 7 days;

(3) and after the lime slaking is finished, weighing the slaked wet lime powder, putting the slaked wet lime powder into a mortar stirrer container, adding water into the container according to the water-to-glue ratio in the sample preparation process, starting the stirrer, slowly stirring (140 revolutions per minute) for one minute, quickly stirring (285 revolutions per minute) for half a minute, and circulating for three times to obtain the newly-prepared white mortar which is uniformly stirred.

And curing the mortar in a room at normal temperature and humidity for 72 hours after the mortar is put into a mold, demolding, and placing the demolded sample in the room at normal temperature and humidity for further curing for 60 days.

The water-to-gel ratio in the ash-sealing process in the step (2) is preferably 0.5-1, and more preferably 0.6; the water-to-gel ratio in the sample preparation process in the step (3) is preferably 0.02-0.1, and more preferably 0.05.

Wherein, the massive quicklime is sprayed for a few times in the lime splashing process to ensure that the massive quicklime is in a dry powder state (the water-cement ratio is difficult to control in a non-dry powder state), and is sieved (meshes are used)<0.3cm²) The smoldering ash is prepared by strictly adding water according to the water-cement ratio, uniformly mixing after adding water to ensure that the lime is completely wet, and performing closed storage to avoid air contact and water evaporation, wherein the closed storage time is not less than 7 days. The ash smoldering process has qualitative effect on whether the hydrated lime powder can be used for ancient architecture renovation. In the traditional method, blocky quicklime is sprayed with excessive water, is stacked after being sprayed into a mooncake wet powder state, and can be used for construction after being stacked for more than half a month and less than half a year. According to the invention, by controlling the ash smoldering water quantity, the ash smoldering is sealed by excessive water, the curing is accelerated, and the sample can be prepared after 7 days.

The index for evaluating the rationality of the ash blocking method is the macroscopic morphology change of the sample after sample preparation and maintenance.

Compared with the samples prepared in different time stages of ash smoldering in the traditional method after 7 days of ash smoldering, the samples prepared in the traditional method are maintained, and the macro morphology of the samples after the maintenance can reflect the state of the samples after actual construction through the rationality of the macro morphology analysis method, so that whether the materials can be used for actual repair can be identified.

The indexes and methods for evaluating the performance of the sample after maintenance mainly comprise the following indexes:

(1) apparent relative density, water absorption and open porosity

The density, the water absorption and the porosity all have certain influence on the freeze-thaw resistance, the water resistance, the strength and the like of the material, indirectly influence the performance of the sample, and are one of the most important parameters of the sample.

The specific test is based on the principle of Archimedes drainage method in terms of density, water absorption and porosity, and is measured by a density balance.

(2) Mechanical properties

The mechanical property of the sample is mainly characterized by compressive strength and rupture strength, wherein the compressive strength refers to the strength limit of the material for resisting external force when external pressure is applied; the flexural strength refers to the ultimate breaking stress of a material when the material bears a bending moment per unit area. By utilizing the analysis of the compressive strength and the flexural strength, the capability of the sample for resisting the damage of the external environment when being used for the historic building can be well measured.

The compression and bending strength is measured by a microcomputer servo compression and bending tester.

(3) Water resistance

When rainfall is high, the interior voids of the historic building mortar become filled with water, and the water resistance can characterize the structural stability of the mortar under long-term water erosion. The water damage to the material performance is reflected in different aspects, the most obvious performance is that the mechanical property of the material is reduced, and the water resistance of the sample is represented by the change of the compressive strength because the bonding force between internal mass points of the material is weakened after the material absorbs water, so that the strength of the material is reduced to different degrees.

The specific test method comprises the following steps: soaking the sample in deionized water for 90 days, drying in a 60 ℃ oven to constant weight, measuring the compression strength of the soaked sample by a microcomputer servo compression and bending tester, and comparing the measured compression strength with the compression strength of the sample before soaking.

(4) Freeze-thaw resistance

Freeze-thaw resistance is used to characterize the structural stability of the material under the dual effects of water and temperature. Water reserved in pores of the sample freezes at low temperature and expands in volume to damage the structure near the pores, and after the temperature is increased, ice melts to reserve larger pores, so that the phenomenon that the macrostructure of the circulating sample is damaged, cracks, falling and the like are generated, the sample loses the corresponding capacity, and the freezing and thawing resistance has important significance for researching the stability of the building under the condition of temperature alternation and rainwater erosion.

The specific test method comprises the following steps: soaking a sample in room-temperature deionized water to saturate the sample, then putting the sample into a freezer at the temperature of-20 ℃ for not less than 4 hours during freezing, putting the sample into water at the room temperature for not less than 4 hours during thawing, and recording the cycle number when the macroscopic pulp is damaged in the experimental process.

(5) Carbonization rate

When the mortar is used for construction, the hydrated lime is gradually carbonized in the air, and the strength is gradually increased along with the carbonization process, so that the higher the carbonization degree is, the higher the strength is, the better the mortar can obtain the high strength. Lime as the main component Ca (OH)₂In basic form, CaCO after carbonization₃The phenol phthalein is alkali-free, and the carbonization speed of the sample can be represented by the characteristic that the phenol phthalein turns red when being subjected to alkali.

The specific test method comprises the following steps: breaking the sample along the cross section direction, dripping 1% phenolphthalein alcohol solution on the surface by using a dropper, wherein the section color development area is an uncarbonated area, the white uncolored area is a carbonised area, and recording the average value of each surface carbonization depth and the average value of the total carbonization depth.

The invention has the beneficial effects that: the method improves the use pretreatment method of the traditional quicklime blocks such as splashing lime, smoldering lime and the like, shortens the preparation period of the slaked lime, avoids deterioration and waste, and avoids potential safety hazards caused by cracking. The blocky quick lime is mixed with the pulverized lime for use, the pulverized lime is utilized to the maximum extent under the condition that the pulverization of the blocky lime is difficult to avoid, the performance of a sample is not reduced, partial performance is improved, and the problem of serious waste of resources is avoided. The optimum block powder ratio of the blocky lime doped pulverized lime mortar is 60:40, compared with the mortar prepared from pure blocky quick lime, the blocky lime doped pulverized lime mortar only slightly reduces the apparent density, increases the water absorption and the open porosity, keeps the same level on the freeze-thaw resistance, slightly improves the water resistance, and obviously improves the mechanical strength and the carbonization speed.

Description of the drawings:

FIG. 1 shows the macroscopic morphology of a sample after sample preparation and maintenance by different ash-sealing methods. a) CT-7; b) CT-15; c) CT-28; d) CT-56; e) GJ-7.

FIG. 2 mechanical Strength of mortar samples

FIG. 3 compressive Strength before and after immersion of mortar sample

Fig. 4 shows the morphology and the number of freeze-thaw cycles before and after freeze-thawing of the mortar samples. a) Before freezing and thawing cycle of mortar samples; b) carrying out freeze-thaw cycling on the sample BH-1 for 7 times; c) carrying out freeze-thaw cycling on the sample BH-2 for 7 times; d) sample BH-3 is subjected to freeze-thaw cycle for 5 times; e) Carrying out freeze-thaw cycling on the sample BH-4 for 3 times; f) carrying out freeze-thaw cycling on the sample BH-5 for 3 times;

FIG. 5 is a schematic view of a cross section of mortar after dropping a phenolphthalein solution.

Detailed Description

The invention is further explained below in connection with the concrete preparation of the mortar and the associated performance test data, but the invention is not limited to the following examples.

Example 1

In order to research the rationality of different ash smoldering methods, the invention firstly adopts hydrated lime prepared by two ash smoldering methods to compare the macroscopic morphology of the sample, the water-cement ratio of the two methods is difficult to unify, in order to make the result more persuasive, the uniform fluidity is adopted for preparing the fresh mortar of the sample, and the detailed information of the sample is shown in the table 1.

TABLE 1 sample details

FIG. 1 shows the macroscopic morphology of a sample after sample preparation and maintenance by different ash-sealing methods. The graph shows that CT-7, CT-15 and CT-28 have serious cracking, which indicates that more chronic lime still exists after lime is stacked for 28 days in the traditional method, the lime still continuously reacts after sample preparation to cause expansion cracking, the cracking phenomenon disappears after the lime is placed for 56 days, the construction period is obviously delayed in construction, and potential safety hazards are caused when the lime is used in advance for shortening the construction period; meanwhile, moisture exists in wet powder after splashing lime, the moisture provides a condition for carbonization, and the wet powder can be seriously deteriorated after being stacked for too long time, so that the quicklime cannot be completely cured, two adverse results of aggravation of the slaked lime are caused, and time nodes are difficult to control. The method disclosed by the invention is used for splashing ash into dry powder, excessive water is added to seal ash to accelerate curing, samples are prepared after 7 days, the cracking phenomenon of the samples does not occur, the residual amount of the chronic ash is small, the ash sealing effect is good, and if the contact with air can be avoided, the deterioration can be avoided. In addition, the method also has the advantages of easy control of water-cement ratio, easy sieving of dry powder, waste avoidance, slow carbonization and deterioration and the like.

Example 2

Table 2 details of raw materials in ash sealing;

table 3 detailed mixture ratio of raw materials when preparing samples;

table 4 mortar samples 60 day density, open porosity and water absorption;

in order to study the performance difference between the mortar prepared by doping blocky quicklime with powdered lime and the mortar prepared by pure blocky lime and powdered lime, 5 groups of experimental proportions in tables 2 and 3 are designed, and samples are sequentially named as BH-1, BH-2, BH-3, BH-4 and BH-5. The mortar was prepared essentially identically, taking BH-2 as an example: sieving (mesh)<0.5cm²) Separating blocky quicklime and powdered lime, stacking blocky quicklime, spraying deionized water in small amount each time, spraying blocky quicklime into dry powder state, and sieving to obtain splashed lime. Weighing 1200g of splashing lime and 800g of powdered lime (the content of calcium carbonate in the powdered lime in the embodiment of the application is 18%), putting the weighed splashing lime and the powdered lime into a container with enough volume, adding 1200g of water into the container, uniformly mixing until the lime completely reaches a wet powder state (the water-cement ratio is 0.6), and sealing and placing the container; weighing 1800g of well-sealed hydrated lime wet powder after 7 days, putting the weighed hydrated lime wet powder into a mortar stirrer container, adding 90g of water (the water-cement ratio is 0.05) into the container, starting the stirrer, slowly stirring for one minute (140 revolutions per minute), quickly stirring for half a minute (285 revolutions per minute), and circulating for three times to obtain newly-prepared white mortar which is uniformly stirred; placing into a 40 x 160mm mold, compacting and leveling the surface, maintaining for 72 hours under indoor normal temperature and normal humidity, demolding, placing the demolded sample under indoor normal temperature and normal humidity, and thenAnd (5) continuing curing, and performing performance test after curing for 60 days.

TABLE 2 detailed ratio of raw materials (g) in ash-sealing

TABLE 3 detailed compounding ratio (g) of raw materials in sample preparation

TABLE 4 apparent relative density, open porosity and Water absorption at 60 days curing of mortar samples

Table 4 shows the apparent relative density, water absorption and open porosity of the mortar samples maintained for 60 days. When the pulverized lime is used for replacing part of the blocky quick lime to prepare mortar, as the ratio of the pulverized lime to the total lime is increased, the apparent density of a sample is gradually reduced, the water absorption rate and the porosity are gradually increased, the damage risk of the mortar when water activities are frequent can be increased due to the reduction of the density of the sample and the increase of the water absorption rate and the porosity, wherein the BH-2 has the smallest change range, is closest to the performance of pure blocky quick lime mortar, and has the smallest potential damage risk.

FIG. 2 shows compressive strength and flexural strength of mortar samples cured for 60 days. After the pulverized lime is added, the compressive strength and the flexural strength of the sample are both improved, and the compressive strength and the flexural strength of the sample with the most pulverized lime are improved to the greatest extent.

FIG. 3 shows the compressive strength of mortar samples before and after immersion in water for 3 months. As can be seen from the figure, the compressive strength of the sample is improved to a certain extent after the sample is soaked in water, and the adverse effect of water erosion is counteracted by further carbonization processes in the processes of soaking and drying the material, which indicates that the water resistance of the sample is better after 60 days of curing. The compressive strength of BH-1, BH-2, BH-3, BH-4 and BH-5 is respectively improved by 119%, 121%, 120%, 93% and 16%, and the BH-1, BH-2 and BH-3 samples are improved to the maximum extent and have good water resistance; the BH-5 increase was minimal and less water resistant than the rest of the sample, which also corresponds to a greater porosity and water absorption, with more water entering the interior causing it to be subject to more water attack. In conclusion, BH-1, BH-2 and BH-3 have good water resistance.

FIG. 4 shows the change in shape and the number of cycles before and after the freeze-thaw cycle of a mortar sample. The BH-1 and BH-2 are cracked at the 7 th cycle, BH-3 is cracked at the 5 th cycle, BH-4 and BH-5 are cracked at the 3 rd cycle, and the BH-2 freeze-thaw resistance cycle capability is not obviously reduced compared with that of a pure blocky lime sample BH-1, the freeze-thaw resistance capability of a mortar sample is reduced after the ratio of pulverized lime to the ratio of pulverized lime is higher than the ratio, and particularly the freeze-thaw resistance capability is reduced by more than 50% after the ratio of pulverized lime to the ratio of pulverized lime reaches 50%.

By combining the apparent density, porosity and water absorption of Table 4 and the results of the freeze-thaw resistance cycle performance test of FIG. 4, the freeze-thaw resistance cycle performance and water resistance of BH-3, BH-4 and BH-5 are reduced, which indicates that the resistance of the mortar to water erosion is reduced after the powdered lime reaches a certain proportion, and simultaneously, the compactness is reduced greatly, and the porosity and water absorption are increased. But the freeze-thaw cycle resistance and water resistance of BH-2 are not reduced, which indicates that increasing the ratio of powdered lime to a certain extent does not significantly adversely affect the performance of the mortar after water attack.

FIG. 5 is a schematic view showing a cross section of a mortar sample after curing for 60 days, on which phenolphthalein solution was dropped, white regions were non-carbonized regions and colored regions were carbonized regions. Obviously, the areas of the carbonization areas of the samples BH-1 to BH-5 are gradually increased, namely, the increase of the proportion of the powdered lime is beneficial to the acceleration of the sample carbonization speed, the increase of the carbonation speed is beneficial to the material to obtain higher strength more quickly, and when the mortar is used as a structural adhesive, the high strength can reduce the risk that the structure is damaged by external force.

Table 5 shows the average value of the carbonization depths of the respective surfaces of the sample, and the average value of the depths of the color development zones of the respective surfaces in FIG. 5. The carbonization depth of the samples and the proportion of the powdered lime form a positive correlation, the average carbonization depth of each group of samples is 100 percent, 28.6 percent, 13.9 percent and 24.4 percent in sequence relative to the growth rate of the previous group of samples, wherein the BH-2 phase has the largest carbonization depth growth rate compared with BH-1, the BH-2 dust doping amount has the highest improvement efficiency, and the BH-5 phase has the largest carbonization depth (namely the fastest carbonization) compared with BH-1.

TABLE 5 sample carbonization depth

In conclusion, the performance test results of the multiple groups of doped powdered lime mortars show that compared with pure blocky quick lime mortar, the mortar BH-2 (the doped powdered lime accounts for 40%) has weak reduction in apparent density, porosity and water absorption rate, but the freeze-thaw resistance and water resistance under the action of water erosion are not affected, in addition, the mechanical property is slightly improved, the carbonation speed is accelerated, and the improvement efficiency is the maximum, so that 40% is the optimal proportion when the powdered lime is doped, and the optimal block powder proportion of the blocky lime doped powdered lime mortar is 60: 40.