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After the earthquake of Tabas at 19:36 pm in September 16, 1978, a large part of the buildings were destroyed and there were many human casualties. With more research, it can be seen that a significant number of these damages and losses from the earthquake had been related to rural buildings around the city (Tabas). Due to the fact that the Tabas area has a warm, dry and desert climate, Villages that suffered such damages were mostly mud and adobe structures. One of these villages is Isfahak (located 38 km south-east of Tabas city) that based on available evidence has a historical background from the Safavid period, As an example of the rural adobe fabric in the Tabas area, it suffered damage and destruction in various dimensions of its physical fabric during the earthquake. According to local information, about 80 people of inhabitants died due to this natural occurrence, and a few others suffered physical and psychological damages. This adobe fabric has been registered as an interesting example of Iran's climatic technology and traditions in relation to rural housing. The use of traditional and local materials in Iranian architecture is now listed in the National Iranian monuments List No. 31336, and in recent years, with the tendency of local people, and especially the desire of educated young people to stay and reside, brings potential opportunity for tourism to growth. The heritage value of the village of Isfahak along with its physical and cultural-social values and the aspect of reminding a historical event (Tabas earthquake as one of the largest and most deadliest earthquakes in Iran) affecting the lives of the people of this region, has created a collection of various values and potentials that need to be protected and rehabilitated. On the other hand, considering the probability of the occurrence of an earthquake and its related financial and death threats for rural adobe buildings is needed to research for raising the level of safety and seismic function in such buildings. Therefore, this study after investigating the most important structural weaknesses of damaged adobe buildings due to the effect of this earthquake and categorization of the seismic damages, then how to strengthen the adobe buildings of Isfahak village. The research method is descriptive-analytical and the data collection had been done via the means of literature review and field observation. By studying similar and successful previous experiments and researches on how to improve seismic performance of adobe buildings and considering different aspects of the problem during frequent field visits from the earthquake site located in Isfahak, in relation to seismic consolidation of these buildings, were proposed three designs: A, B and C. The designs were evaluated and compared in terms of theoretical principles of architectural heritage restoration and seismic function validation by modeling in the ANSYS software. Finally, the design of B (the application of wooden elements and woven ropes from palm fiber to integrate structural behavior of building components) due to the most consistency with the policies and strategies defined in relation to how to perform the intervention as an optimal seismic consolidation model for adobe buildings of Isfahak village were proposed. In fact, the project has been performed through seismic authentication and is more consistent with the theoretical principles of restoration. In addition to the economic feasibility and ease of implementation as two important criteria for attracting local people's participation, more than two other projects are considered in this plan.

The importance and the value of historical buildings and sites and even villages which have adobe houses causes that conservators annually schedule restoration plans and programs to protect the buildings from hazards. This is done because conservation of these memorials is equal to conservation of culture, civilization, heritages of a nation, their architecture, and their lifestyle. There are many damaging factors for an adobe building being always a threat for its skeleton. Causing irreparable harms independently or dependently, moisture is one of the damaging factors for adobe buildings. Optimizing the repairing materials in conservation, repair, and reconstruction of adobe buildings to increase their resistance against moisture and other damaging factors is one of the suitable methods for protecting these buildings worldwide. Until today, many additive materials have been tested and occasionally applied regarding the enhancement of the physical and environmental properties of the buildings. Lime is a conventional locally supplied material, had been originally used in areas with high humidity and heavy seasonal rainfall. In this research a number of buildings in the North and North West of Iran have been selected as the case study where the lime was used as the adobe optimizer. This research aims to find a mix of adobe which is compatible with the highly humid environment (saturated adobe) as well as having high physical quality and a relative strength against other damaging forces. Now, the question is that by adding lime to soil as a traditional material that absorbs water and is resistant to moisture, can it be possible to increase the stability of these adobe against moisture, as well as their physical properties to keep compressive resistance and abrasion resistance? The research hypothesis suggests that because of low adhesion and poor bonding between lime and soil and low humidity in open spaces, it is likely that by adding lower percentages of lime, a more favorable result can be achieved. For this aim, five mix of adobe were made containing 0, 2, 5, 7 and 10 percentage of lime. The samples undergone multiple mechanical tests: compressive resistance in dry and saturated condition, abrasion resistance, capillary absorption and resistance to immersion tests. The results show that lime is affective on physical properties of adobe in such a way that by increasing the amount of lime aforementioned, the compressive strength and abrasion resistance decreases by a significant amount. Capillary test results show that, the increase in the amount of lime in the mix causes the increase in the speed of capillary absorption. This characteristic of lime causes using preparing adobes having lime in reconstruction of walls be an ideal solution to conserving the old internal wall adobes. This is because the exposure of water and moisture are absorbed by this kind of adobe due to the higher level of lime concentration in the mix portion and the main old structure of the wall absorbs the minimum amount of the water and remains safe from abrasion. Based on the results of pressure resistance test on the wet and dry adobe samples and also their resistance against immersion, only 2% added lime cause to keep the physical resistance of adobe compares to the other samples, impressively. According to the results of the tests done in this research and its purpose, among tested adobe samples, the sample number 2 having 2% added lime is estimated as the best optimized sample. In this way, its resistance to compressive and abrasion is higher than other lime samples, as well as its resistance to water immersion and its compressive strength after soaking from all specimens, even the lime sample was higher This optimization of the crude clay and its resistance to water saturation conditions is the same as the desired result and the purpose that this research seeks to do.