Mavzu-12: Bino va uning konstruktiyasi emirilish darajasini baholash

Mnp _
R b ^
Rs _{ 2R2b } Rb
(29)

 ^b   b 
Xuddi shuningdek, egiluvchi elementlar uchun statistik tavsilotlar formulalarini keltiramiz. Qush armaturali egiluvchi elementning yuk ko‘tarish qobiliyati (_R) quyidagicha aniqlanadi
^ R_S A_S^{ }

M  R_bbxh_o  0,5x ^

h

 a^ 


(30)

Siqiluvchi zona balandligi

 o 

bundan


_{x } N
R_bb
R_bbx  R_S A_S


;

• 
  ^RSC ^AS^C
  

Agarda (30) formulani X qiymati bilan qayta ifodalasak, unda

 _N 
₁  _N  _N 

R_bb^ _{R b} ^h_o 
^{  }  R_S A_S h_o  R_SC A_S^ a

 b 
2R_bb _ R_bb _ R_bb _

 _N ² 

M  Nh_o  ^ _{2R b} ^  R_S A_S h_o  R_SC A_S^ a
(31)

 b 
Ikkala hol uchun ularning matematik kutilmasi va dispersiyalarini aniqlaymiz.
h_o o‘zgaruvchi bo‘lgan holda.
Bunda (7) formula bo‘yicha matematik kutilma
^ R A  R A^^{2 }

^M np
 R_S A_S h_o  ^

S S SC
2R_bb
^  R_SC A_S^ a^

(32)

(9) formula bo‘yicha dispersiyasi

D  R ² A² D
(33)

Mpr s s ho
b o‘zgaruvchan bo‘lgan holda

^ R A  R A^ ^{2 
} R A
 R A^ ^{2 }

^M np
 R_S A_S h_o  ^{ S S SC S }  R_SC A_S^ a^  ^{ S S}
S S _Db

b
(34)
_ 2R_bb _
 2R b³ _

^ R A  R A^ ^{2 }2

^DMnp ^{  S S}
SC S
 _Db

b




^ 2R b^{2 }
(35)

R_b o‘zgaruvchan bo‘lgan holda

 _N ²  ₁  _N ² 

^M np
 Nh_o  ^{ }  R_S A_S h_o  a ^ ₃ ^D_Rb


(36)

2R b 2 R b
 b 
 _N ² ²
 b 

D_Mnp  ^ _{2R b} ^
DRb
(37)

 b 
R_s o‘zgaruvchan bo‘lgan holda
 _N ² 

^M np
 Nh_o  ^{ }  R_S A_S h_o  a
2R b


(38)

 b 

^ A h  R A^{2 2}

_{DMnp  } S o S S _
^DRs
(39)

 ^Rb^b 

R_s va R_b o‘zgaruvchan bo‘lgan hollarda

 _N ²  ₁  _N ² 

^M np
 Nh_o  ^ ₂ ^  R_S A_S h_o  a ^ ₃ ^D_Rb


(40)

2R b 2 R b
 b 
 _N ² 
 b 

D_Mnp  ^ _2R2b ^
D_Rb  Ah_o  a2D_Rs
(41)

 b 

N (yuk) o‘zgaruvchan bo‘lgan holda

 _N ²  ₁  ₁ 

^M np
 Nh_o  ^{ }  R_S A_S h_o  a ^ ^D_N
2R b 2 R b


(42)

 b   b 
^ h  N ^2

D_Mnp  ^{ o } D_N
(43)

 ^Rb^b 
N,R_b,R_s parametrlari o‘zgaruvchan bo‘lgan hollarda

 _N ² 
 ₁ 
 _N ² 

^M np
 Nh_o  ^{ }  R_S A_S h_o  a ^{ }D_N
2R b 2R b

• 
  ^ _{2R b} ^D_Rb 
  

 b 
 b 
 b 

^ 1 ^ N ²  D  N ²D ^
(44)

 Nh_o  ^{  N Rb }  R_S A_S h_o  a
^ 2R b ^ R²b ^
 b  
 _{h  N} ²  _N ² ²
D  ^{ o } D  A h  a² D  ^{ } D

Mnp
_{ R b } N S o
Rs _{ 2R2b } Rb
(45)

 b   b 


Bu formulalar yordamida har bir konstruktiv elementning mumkin bo‘lgan variatsiya koeffitsiyentlari yordamida ikki bosqichli hisoblash, yaʼni dastlabki berilgan holat (1-bosqich) va ekspluatatsiyaning turli bosqichlarida tekshiruv ishlaridan olingan maʼlumotlar asosida (2- bosqich) qayta hisoblash natijasida ularning ekspluatatsion ishonchliligini baholash mumkin.