The Research On Suitable Value Of The Distance Between Teaching Space And Sports Field Based On Code For Design Of School

Since 1987,the first edition of code for design of school was published,the construction of schools has been based on the code 30 years.In 2011 the new code for design of school was published,comparing with the first code 84% of the content having changed.The rule about the distance between the teaching space and sports field changed from “the distance between the long-side of the teaching building to the sports field cannot be less than 25meters” to “the distance between external windows of the classroom and the sports field cannot be less than 25meters”.We can find the rule of the distance between teaching building and sports field become increasingly strict.We find the cause in the interpretation of the new code that is when the distance between the teaching building and sports field is over 25 meters the equivalent sound level of noise on the edge of sports field is between 70 d B to 75 d B,but when the noise was propagated to classrooms it decreased to 50 d B and below.When the equivalent sound level of the classroom is less than 50 d B it is a good teaching environment.However there are lots of schools whose distance between teaching space and sports field is less than 25 meters in our country because of shortage of land and other reasons.Do the equivalent sound level of the classroom is always over than 50 d B on gym classroom when the distance is less than 25meters?To study this problem in this paper the author made detailed field research in 5 schools whose distance between teaching building and sports field is less than 25 meters.The space environment and building space of the schools were mapped in detail in the field research.And the equivalent sound level in the classroom was measured under the impact of the noise from the sports field.By organizing and analyzing the data measured in TYL primary school and middle school.The degree of attenuation of the noise from the edge of sports field was got when it propagated to two kinds of classroom.One's external window faces to the sports field.Another's gable faces to the sports field.In the meantime,we also get the difference of the sound attenuation in two kinds of classroom are the same when the noise is from the short edge or from the long edge.Another conclusion was made when the outside was on gym class the equivalent sound level on the edge of field sports is proportional to the number of the students on the sports field.And it is inversely proportional to the per capita outdoor sports area.The lower limiting values of the distance between teaching space and sports field in three schools were got by the experiment in which the noise source was put in different distance and the equivalent sound level in the classroom were measured to compare with the standard values.The noise on the edge of sports field in different schools is different.And the lower limiting values are also different.When the distance of teaching space to sports field is less than 25 meters,the measures which can be taken to reduce the influence of noise are summarized in the paper.Since the limitation of time and energy,the paper focuses on the noise impact to the distance and ignores the fireproof,sunlight and so on.To prevent the other noise source to effecting the result,the background noise sound level was measured and found that it can be ignored.In the final,the author looks forward to the research on the suitable value of the distance between two teaching buildings.And there is a liner equation guessed among the noise equivalent sound level on the edge of sports field,the number of the students in outdoor gym class and per capita outdoor sports area.