Method of determining the number of shot holes fired safe for a protected single-family building, taking into account the value of vibration velocity and frequency of the horizontal tangential component measured on the building

摘要

Method of determining the safe number of shot holes for the protected single-family building, taking into account the value of the speed and frequency of horizontal convulsions useful in planning the total load of explosives used for the shooting. For the determination of the harmfulness of vibration during single-line shooting of the building jOne-family use SWD I Dynamic Impact Scale and description of damage occurring in the damage building characterising Zone II and Zone III. Having measured the component value of the horizontal contact speed Vy and its corresponding frequency on the SWD scale I we find a point of intersection of the horizontal component value Contact vibration rate Vi and its frequency to be determinedwhether it is located in Zone III with damage to the building described in SWD I as a breach of the structure or a danger to the protected house. If the debris approached the protected object, yes, that measurements along one of the axis of the house in the direction of the component of the horizontal contact rate of vibration Vi at the height of the ground level and its frequency have shown that the point of intersection is Zone III, reducing the frequency of vibration can be achieved with the same charge of explosive material in the hole and for a delay temporary,i.e. at the same rate of vibration, shift the harmful effects of the vibration on the house from zone III to zone II. This is done by adding to the previously opened series several arrow holes fired with delay (delay) compared to the previous hole,where the size of the explosive load launched in the hole and for one delay is the same as in the holes previously fired and the following operations are carried out in succession. For the composite horizontal contact vibration speed Vi of the measured frequency shall be calculated according to its vibration period in (ms). In the amount of holes opened, we add two more holes with a delay (corpse) in (ms) and we getand 2 open the sum of the time 2 delays after which the second vibration amplitude from the next hole is applied to the vibration period with the measured component frequency of the horizontal contact vibration velocity Vi. Next we calculate the ratio of the sum of the two hole delays to the measured component period of the horizontal contact velocity Vi. And we're reading from the analysis of the vibration deposition at approximate frequencies.that for a given value of this ratio, the vibration period with the measured component frequency of horizontal vibration velocity Vi shall be increased by multiplying by a factor greater than unity. By multiplying the time period of vibration of the measured component frequency of the horizontal contact rate of vibration You will get more time of the vibration period by the factor increasing its value and by that,the lower previously measured component frequency of horizontal V-stroke stroke. Then we check on the dynamic impact scale SWD I whether the point of intersection of the reduced component frequency of the horizontal contact vibration speed Vi and the unchanged component value of the horizontal contact vibration speed Vi is outside Zone III. If not,calculate as above for three holes by checking again whether the point of intersection of the reduced component frequency of the horizontal contact speed Vi and the unchanged component value of the horizontal contact speed Vi is outside the zone III. If not, we do the calculations again increasing the number of holes one more hole and so many times,until the point of intersection of the reduced component frequency of the horizontal contact vibration speed Vi and the unchanged component value of the horizontal contact vibration speed Vi is located outside Zone III or safe for the Building Zone II because there are no vibrations causing cracks in the structure of the building. In doing so, discovered and proven,that, in order to protect the building from the destructive effects of vibration, it is not necessary to reduce the amount of cargo that has been fired up to now by one delay but to increase the number of holes that have been fired by the same amount of cargo in the hole and for the same amount of time as before. This method applies to single-line shooting.