To‘g‘ri to‘rtburchak shakldagi plastinka egilishlari va sirti elliptik paraboloid bo‘lgan qobiqlar hisobi masalalari

O’ZBEKISTON RESPUBLIKASI	 	
OLIY VA O’RTA MAXSUS TA’LIM VAZIRLIGI	 	
 	
SHAROF RASHIDOV NOMIDAGI SAMARQAND 	
DAVLAT UNIVERSITETI	 	
 	
MATEMATIKA FAKULTETI	 	
 	
NAZARIY VA AMALIY MEXANIKA 	KAFEDRASI	 	
 Plastinka va qobiqlar nazariyasi	 fanidan 	 	
MUSTAQIL ISH	 	
Mavzu: 	Tog’ri 	to’rtburchak sha	kldagi plastinka 	
egilishlari	 va sirti elliptik paraboloid bo’lgan qobiqlar 	
hisobi masalalari	 	
                                                                    	 	 	 	 	 	 	 	
 	 	 	Bajardi:____	-guruh talabasi _________________	 	
              	 	
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               	                             	Mustaqil ish qabul qilingan vaqt_________	 	
 	
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keltirilishi talab etiladi.	 	
 	
Tog	’ri	 to	’rtburchak	 shakldagi	 plastinka	 egilishlarini	 hisoblash	 	
Asosiy tushunchalar	 	
A s o y i y   t e n g l a m a l a r . C h e g a r a v i y   s h a r t l a r .	 	
 	Plastinka  egilishlari  uchun  muvozanat  diierensial  tenglama  (Sofi  Jerman 	
tenglamasi):	 	
??????4�	
??????�4	+	2	
??????4�	
??????�2??????�2+	
??????4�	
??????�4	=	
�(�,�)	
�	                              (1) 	
bu 	yerda	 �	=	??????ℎ3	
12	(1−??????2)  plastinka ko’ndalang kesimi silindrik bikrligi.	 	
 	Ichki zo’riqish	 kuchlari quyidagi formulalar orqali aniqlanadi:	 	
 	а) � va 	� o’qli normalli ko’dalang kesimdagi eguvchi momentlar mos ravishda:	 	
{
 
 
 
 �	�	=	−	�	(
??????2�	
??????�2	+	�
??????2�	
??????�2)	
�	�	=	−	�	(
??????2�	
??????�2	+	�
??????2�	
??????�2)
                                             (2) 	
 	b) k	o’ndalang 	kuch intensivligi:	 	
{
 
 
 
 ��	=	−	�	(
??????3�	
??????�3	+	�	
??????3�	
??????�??????	�2)	
��	=	−	�	(
??????3�	
??????�3	+	�	
??????3�	
??????�??????	�2)
                                             (3) 	
 	с) b	urovchi moment intensivligi:	 	
??????	=	−	�	(1	−	�)	
??????2�	
??????�??????�	                                                       (4) 	
 	(1)  tenglamani  yechishdan  hosil  bo’ladigan  inte	grallash  o’zgarmaslari 	
chegravi	y  shartlardan  topiladi.  Chegaraviy  shartlar  chegarada  kinematik  va  statik 	
parametrlarni berilishiga qarab  gruhlarga ajratiladi. Bular:	 	
 	1. Kinematik 	– ko’chish va burilish burcha	gi berilgan:	 	
�) � �������??????	 ���??????���	 �	,??????�	=	
??????�
??????�	 	
�) � �������??????	 ���??????���	 �	,??????�	=	
??????�
??????�	 	
 	2. Statik 	– ichki zo’riqish kuchlari berilgan:	  �) � �������??????	 ���??????���	 �	�,��,??????	 	
�) � �������??????	 ���??????���	 �	�,��,??????	 	
 	3. Aralash 	– bir qism ko’chishlar  va ichki kuchlar berilgan.	 	
 	Rasmda plastinka o’rta sirti mahkamlanish	i ko’rsatilgan. 	 	
 	
Plastinka barcha tomonlari uchun chegaraviy shartlarni keltiramiz:	 	
1. 	�	=	0  bo	’lgan tomon uchun  	 	
??????	=	0; �	�	=	−	�	(
??????2�	
??????�2	+	�
??????2�	
??????�2)	=	0,                              (5) 	
(aralash guruh).	 	
2. 	�	=	�  bo’lgan tomon uchun  	 	
??????	=	0; �	�	=	−	�	(
??????2�	
??????�2	+	�
??????2�	
??????�2)	=	�̅,                              (6) 	
(aralash guruh).	 	
 
3. 	�	=	0  bo’lgan 	tomon uchun  	 	
??????	=	0; ??????�	=	
??????�
??????�	,                                                    (7) 	
(kinematik guruh).	 	
4. 	�	=	�  bo’lgan tomon uchun  	 	
�	�	=	0; �̅�	=	−	�	(
??????3�	
??????�3	+	(2	−	�)
??????3�	
??????�3)	=	0,                              (8) 	
(statik guruh), bu 	yerda  	�̅�	−	 keltirilgan ko’ndalang kuch intensivligi.	 	
 	1-M i s o l .  	To’gri to’rtburchak shakldagi egiluvchan plastinka berilgan (1	-a,b	 	
rasm	).  Egilish  funksiyasi  va  yuklanis	h  1	-jadvalda,	 son  qiymatlari  esa  2	-jadvalda 	
berilgan.	  	
 	Quyidagilarni aniqlang:	 	
1. Plastinka 	tomonlarini mahkamlanish shartlarini toping.	 	
2. 	� o’zgarmasni aniqlang	 	
3. Ichki kuchlar ifodasini toping.	 	
 	4.  Ichki  zo’riqish  kuchlari  epyurasini  kesimlarning  birida  quring: 	
�	−	kesimdagi 	�	�,��; �	−	kesimdagi 	�	�,��.    	
1-rasm	 	
1-jadval	 	
 	Plastinka	 ko	’rinishi	 1- rasmda	K �(�,�) yuklanish	 va	 ??????	(�,�)egilish	 	
funksiyalari	. �	,� va 	�0−	o’zgarmas kattaliklar.	 	
0 	 1.�) ����	.�	=	�����	,	�	=	�(�	−	�)2(�	−	�)2 	
1 	1.�) ����	.�	=	�����	,	�	=	���	(�	−	�)(�	−	�) 	
2 	1.�) ����	.�	=	�0�??????�	
??????�
�	�??????�	
??????�
�	;   �	=	��??????�	
??????�
�	�??????�	
??????�
�	 	
3 	1.�) ����	.�	=	�0�??????�	
??????�
�	�??????�	
2??????�
�	;  �	=	��??????�	
??????�
�	�??????�	
2??????�
�	 	
4 	1.�) ����	.�	=	�0�??????�	
2??????�
�	�??????�	
??????�
2�	;  �	=	��??????�	
??????�
�	�??????�	
??????�
2� 	
5 	1.�) ����	.�	=	�0�??????�	
??????�
�	���	
??????�
2�	;    �	=	��??????�	
??????�
�	���	
??????�
2� 	
6 	1.�) ����	.�	=	�0���	
??????�
2�	�??????�	
??????�
�	;    �	=	����	
??????�
2�	�??????�	
??????�
�	 	
7 	1.�) ����	.�	=	�0�??????�	
2??????�
�	���	
??????�
2�	;    �	=	��??????�	
2??????�
�	���	
??????�
2� 	
8 	1.�) ����	.�	=	�0���	
??????�
2�	�??????�	
2??????�
�	; �	=	����	
??????�
2�	�??????�	
2??????�
�	 	
9 	1.�) ����	.�	=	�����	; �	=	�(�2−	�2)(�	−	�)2 	
2-jadval	 	
Variant oxirgi raqami	 	�	 	 
� 	� 	� 	ℎ 	� 	� 	
0 	4 	3 	0.1 	3 	2 	0.35	 	
1 	3 	3 	0.1 	2 	2 	0.30	 	
2 	3 	3 	0.1 	1 	1 	0.25	 	
3 	4 	4 	0.2 	2 	3 	0.25	 	
4 	5 	3 	0.1 	3 	1 	0.30	 	
5 	3 	5 	0.1 	1 	3 	0.30	 	
6 	3 	3 	0.2 	2 	2 	0.35	 	
7 	5 	5 	0.2 	2 	2 	0.35	 	
8 	5 	4 	0.2 	3 	1 	0.30	 	
9 	4 	5 	0.2 	2 	3 	0.30	 	
  N a m u n a v i y   m a s a l a	: 	
Berilgan:	 	
�(�,�)=	�0�??????�	
??????�
�	���	
??????�
�	; �	(�,�)=	��??????�	
??????�
�	���	
??????�
�	; �	=	4;  	
 �	=	3; ℎ	=	0.2; �	=	1; �	=	1; �	=	0.2;   	
1.�) ����	 	
 	1. Plastinka tomonlari mahkamlanishini topamiz.	 	
 	a) �	(�,�)=	0 chegaraviy shartni tekshiramiz.	 	
 	�	=	±	� bo	'lganda	 �	(±	�,�)=	��??????�	??????(±�)	
�	���	??????�
�	=	0 ve	rtikal tayanch bor	. 	
       	�	=	±	� 	bo'lganda	 	�	(�,±	�)=	��??????�	??????�
�	���	??????(±�)	
�	=	−	��??????�	??????�
�	≠	0, 	vertikal	 	
tayanch	 yo	’q. 	
 	b) burilish	 burchagini	 tekshiramiz	. 	
??????�	=	
??????�
??????�	=	�	
??????
�	���	
??????�
�	���	
??????�
�	 	
 	�	=	±	� bo	'lganda	 	
??????�	=	�	
??????
�	���	
??????(±	�)	
�	���	
??????�
�	=	−	�	
??????
�	���	
??????�
�	≠	0 	
 	Bu tomon sharnirli mahkamlangan.	 	
??????�	=	
??????�
??????�	=	−	�	
??????
�	�??????�	
??????�
�	�??????�	
??????�
�	 	
 	�	=	±	� bo	'lganda	 
??????�	=	−	�	
??????
�	�??????�	
??????�
�	�??????�	
??????(±	�)	
�	≠	0 	
 	Bu	 tomon	 harakatlanuvchi	 (	o’qi	 bo	’ylab	) mahkamlangan	. 	
 	2.  	С	 o’zgarmasni topamiz. 	 	
 	Buning	 uchun	 plastinka	 egilish	 tenglamasiga	 �(�,�) yuklanish	 va	 �	(�,�) 	
egilish	 funksiyalari	ni	 qo	’yamiz	: 	
 	Hosilalarni hisoblaymiz:	 	
??????4�	
??????�4	=	�	(
??????
�)
4
�??????�	
??????�
�	���	
??????�
�	; 	
??????4�	
??????�2??????�2	=	�	(
??????
�)
2
(
??????
�)
2
�??????�	
??????�
�	���	
??????�
�	; 	
??????4�	
??????�4	=	�	(
??????
�)
4
�??????�	
??????�
�	���	
??????�
�	; 	
topilgan ushbu ifodalarni plastinka egilish 	teglama	si 	
??????4�	
??????�4	+	2	
??????4�	
??????�2??????�2+	
??????4�	
??????�4	=	
�
�	 	
ga qo’yamiz	 z  �??????4(	
1
�4+	2	
1	
�2�2+	
1
�4)�??????�	
??????�
�	���	
??????�
�	=	
�0
�	�??????�	
??????�
�	���	
??????�
�	 	
 	Bundan	 quyidagini olamiz	: 
�	=	
�0	
�	??????4(	1
�2+	1
�2)
2 	
ekanligi	 kelib	 chiqadi	. 	
 	3. 	Ichki	 kuchlar	 ifodasini	 topamiz	.  	
 	Buning uchun zarur 	bo’	ladigan hosilalarni hisoblaymiz:	 	
??????2�	
??????�2	=	−	�	
??????2
�2�??????�	
??????�
�	���	
??????�
�	; 	
??????2�	
??????�2	=	−	�	
??????2
�2�??????�	
??????�
�	���	
??????�
�	; 	
??????2�	
??????�??????�	=	−	�	
??????2
��	���	
??????�
�	�??????�	
??????�
�	; 	
??????3�	
??????�3	=	−	�	
??????3
�3���	
??????�
�	�??????�	
??????�
�	; 	
??????3�	
??????�3	=	�	
??????3
�3�??????�	
??????�
�	�??????�	
??????�
�	; 	
??????3�	
??????�??????	�2	=	−	�	
??????3	
��2���	
??????�
�	���	
??????�
�	; 	
??????3�	
??????�2??????�	=	�	
??????3	
�2�	�??????�	
??????�
�	�??????�	
??????�
�	; 	
 	Bu	 ifodalar	 yordamida	 ichki	 kuchlarni	 aniqlaymiz	: 	
�	�	=	��	??????2(	
1
�2+	
�
�2)�??????�	
??????�
�	���	
??????�
�	=	�1�??????�	
??????�
�	���	
??????�
�	; 	
�	�	=	��	??????2(	
1
�2+	
�
�2)�??????�	
??????�
�	���	
??????�
�	=	�2�??????�	
??????�
�	���	
??????�
�	; 	
��	=	��	??????3(	
1
�3+	
�
��	2)���	
??????�
�	���	
??????�
�	=	�3���	
??????�
�	���	
??????�
�	; 	
��	=	−	��	??????2(	
1
�3+	
�
��	2)�??????�	
??????�
�	�??????�	
??????�
�	=	−	�4�??????�	
??????�
�	�??????�	
??????�
�	; 	
??????	=	��	??????2	1
��	(1	−	�)���	
??????�
�	�??????�	
??????�
�	=	�5���	
??????�
�	���	
??????�
�	 	
 	4. Ichki kuchlar epyuralarini quramiz	 (2	-rasm).	 	
 	a) �	=	1 �	 bo	’lgan	 kesimda	  	
�	�	=	�1�??????�	
??????�
�	���	
??????�
�	=	0.707	�1���	
??????�
�	. 	
bu 	yerda:	  0.707	�1	=	0.707	
�0(	1
�2+	�
�2)	
??????2(	1
�2+	1
�2)
2	=	0.707	∙	
�0(1
42+	0.2
32)	
3.14	2(1
42+	1
32)
2	=	0.202	�0 	
�	�	=	0.202	�0���	
??????�
�	; 	
��	=	�3���	
??????
4	���	
??????�
�	=	0.707	∙�3���	
??????�
�	; 	
0.707	∙�3	=	0.707	∙
�0(	1
�3+	1
��	2)	
??????	(	1
�2+	1
�2)
2	=	0.707	∙	
�0(1
42+	1	
4	∙32)	
3.14	∙(1
42+	1
32)
2	=	0.325	�0; 	
��	=	0.325	�0���	
??????�
�	; 	
 	b) �	=	1�	 bo	’lgan kesimda	  	
�	�	=	�2�??????�	
??????�
�	���	
??????
3	=	0.5	∙�2�??????�	
??????�
�	 	
0.5	∙�2	=	0.5	∙	
�0(1
32+	0.2
42)	
3.14	2∙(1
42+	1
32)
2	=	0.208	�0; 	
�	�	=	0.208	�0�??????�	
??????�
�	; 	
��	=	−	�4�??????�	
??????�
�	�??????�	
??????
3	=	−	0.866	�4�??????�	
??????�
�	=	−	0.53	�0�??????�	
??????�
�	 	
 	Ichki kuc	hlarni 	� va 	� ning turli qiymatlarida hisoblaymiz 3	-jadval	 	
3-jadval	 	
�	=	1 �	 ���??????���	 	�	=	1 �	 ���??????���	 	
� 	�	�∙�0 	��∙�0 	� 	�	�	∙�0 	��	∙�0 	
0 	0.202	 	0.325	 	0 	0 	0 	
±	1  	0.101	 	0.162	 	±	2 	±	0.208	 	±	0.53	 	
±	1.5 	0 	0 	±	4 	0 	0 	
±	2 	−	0.145	 	−	0.281	 	−	 	−	 	−	 	
±	3 	−	0.202	 	−	0.325	 	−	 	−	 	−	 	
 	
2-rasm	 	
   Sirti elliptik paraboloid bo’lgan qobiqlar hisobi masalasi	. 	
Asosiy tushunchalar	 	
Yotiq qobiq deb qobiq egriligi uning o’lchamlariga nisbatan yetarlicha kichik 	
qobiqlarga aytiladi. Masalan 	�/�	≤	1/5, bu yerda  	�	−	 qobiq ko’tarilish balandligi, 	
� uning tomo	ni.	 	
 	2-Misol. 	To’g’ri burchakli to’rtburchak panelli o’rta sirti ushbu 	 	
�	=	2�	(
�2
�2+	
�2
�2) 	
funksiya bilan ifodalanuvchi 	yotiq	 elliptik paraboloid qobiq egilishini aniqlang	. 	
  	Yechish.	 Qobiq  muvozanat  tenglamalar  sistemasini  quyidagi  ko’rinishda 	
olamiz.	 	
{
∇??????2Φ	(�,�)−	�	∇4�	(�,�)+	�(�,�)=	0	
1
��	∇4Φ	(�,�)+	∇??????2�	(�,�)=	0               
                          (9) 	
bu yerda	 	
∇??????2=	4�	(	
1
�2	
??????2	
??????�2+	
1
�2	
??????2	
??????�2)	;   ∇4=	(	
??????2	
??????�2+	
??????2	
??????�2)
2
; �	=	
�ℎ3	
12	(1	−	�2).  	
   	Koordinata  o’qlari  qobiq  markaziga  joylashtirilgan  bo’	lib  q	obiq  tomonlari 	  	
�	=	±	�/2 va 	�	=	±	�/2  ga teng bo’lsin:	 	
 	bu �	=	±	�/2 chegarada eguvchi moment 	�	�	=	−	�	(??????2�	
??????�2+	�??????2�	
??????�2) va o’rta 	
sirtning egriligi 	??????�	=	??????2�	
??????�2 nolga teng;	 	
 	�	=	±	�/2 chegarada  diagrammaning  cho’zilmasligidan   	�� uzayish  yo’q 	
va uning yupqaligidan 	�� normal zo’riqish yo’q. Guk qonuniga ko’ra 	��	=	
??????2Φ	
??????�2	=	0 ekanligi kelib chiqadi;	 	
 	�	=	±	�/2 tomon  uchun  ham  yuqoridagi  shartlar  o’rinli. 	Agar  qobiq 	
tomonlari  tayanish  chegrasida  gorizontal  tashqi  kuchlar  bo’lmasa,  u  holda 
kuchlanish funksiyasi 	Φ	 bu chegarada nolga teng bo’ladi.	 	
Shunday  qilib,  qobiq  tomonlari  uchun  quyidagi  chegaraviy  shartlar  o’rinli 	
bo’ladi: 	 	
�	=	±	
�
2	 �����	 ��	ℎ��	 �	=	0,
??????2�	
??????�2	=	0,��	=	
??????2Φ	
??????�2	=	0	
�	=	±	
�
2	 �����	 ��	ℎ��	 �	=	0,
??????2�	
??????�2	=	0,��	=	
??????2Φ	
??????�2	=	0
}
 
 
 
 	
         (10	) 	
 	Yechimni  (9	)  muvoza	nat  tenglamalari sistemasi va  (10	)  chegaraviy  shartlarni 	
qanoatlantiruvchi quyidagi ikki karali trigonometrik qator shaklida izlaymiz. 	   �	(�,�)=	∑	∑	��,�	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	
Φ	(�,�)=	∑	∑	Φ	�,�	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	}
 
 
 
 	
                   (11	) 	
bu yerda 	��,�	 va 	Φ	�,�	 sonli koeffi	tsiy	entlar. Tashqi yuklanish 	�(�,�) ko’rinishini 	
quyidagi ikki karali trigonometrik qator ko’rinishda tasvirlaymiz:	 	
�(�,�)=	∑	∑	Z�,�	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	
                              (12	) 	
 	Bu  qatorning  koeffi	tsiye	ntlari  bi	zga  ma’lum  bo’lgan  Fur’	e  qatorlari 	
nazariyasidan kelib chiqib quyidagi formuladan topiladi. 	 	
Z�,�	=	
4
��	∫	∫	�(�,�)���	
�??????�
�	���	
�??????�
�	����	
�
0
�
0	
                   (13	) 	
 	Bu  olingan  (11),  (12)  ifodalarni  (9	)  muvozanat  tenglamasiga  qo’ysak  va  uni 	
���	�??????�
�	���	�??????�
�	  ga qisqartirsak, u holda	 	
??????4�	(
�	4	
�4	+	2	
�	2	
�2	
�2
�2+	
�4
�4)	��,�	+	4�??????2(	
�2	
�2�2+	
�	2	
�2�2)	Φ	�,�	=	Z�,�	; 	
−	4�??????2(	
�2	
�2�2+	
�	2	
�2�2)	��,�	+	
??????4
��	(
�	4	
�4	+	2	
�	2	
�2	
�2
�2+	
�4
�4)	Φ	�,�	=	0. 	
bundan	 	
��,�	=	
1
��	∙	
(�	2	
�2	+	�2
�2)Z�,�	
[�	??????4	
��	(�	2	
�2	+	�2
�2)
4
+	16	�2	
�4�4(�	2+	�2)2]
; 	
Φ	�,�	=	
4	
�2�2∙	
(�	2+	�2)Z�,�	
[�	??????4	
��	(�	2	
�2	+	�2
�2)
4
+	16	�2	
�4�4(�	2+	�2)2]
. 	
Bu formulalarni qisqaroq ko’rinishda yozamiz.	 	
��,�	=	
Z�,�	�4	
��2�	∙	
�4(�	2�2+	�2)2	
??????(�	2�2+	�2)4+	16	�4(�	2+	�2)2;	
Φ	�,�	=	
4Z�,�	�4	
�	∙	
�6(�	2+	�2)	
??????(�	2�2+	�2)4+	16	�4(�	2+	�2).
}
 
 
 
 	
             (14	) 	
bu yerda 	 	
�	=	
�
�	; ??????	=	
�	
�2��	=	
�2	
12	(1	−	�2)�2. 	
 	Agar qobiq kvadrat shaklda bo’lsa, u holda  	�	=	1, s	hunga ko’ra,	  ��,�	=	
Z�,�	�4	
��2�	∙	
1	
??????(�	2+	�2)2+	16	;	
Φ	�,�	=	
Z�,�	�4	
�	∙	
4	
??????(�	2+	�2)3+	16	(�	2+	�2).
}
 
 
 
 	
             (15	) 	
 	Qobiqdagi ichki zo’riqishlarni quyidagicha aniqlaymiz:	 	
��	=	
??????2Φ	
??????�2	=	−	∑	∑	Φ	�,�	
�2??????2	
�2	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	
; 	
��	=	
??????2Φ	
??????�2	=	−	∑	∑	Φ	�,�	
�	2??????2	
�2	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	
;                (16	) 	
??????	=	
??????2Φ	
??????�??????�	=	−	∑	∑	Φ	�,�	
��	??????2	
��	�??????�	
�??????�
�	�??????�	
�??????�
�	
∞
�=1	
∞
�=1	
. 	
 	�	�,�	� eguvchi va 	�	��	 burovchi momentlar esa quyidagi ko’rinishda bo’ladi:	 	
�	�	=	−	�	(
??????2�	
??????�2	+	�
??????2�	
??????�2)	=	�	∑	∑	??????2(
�	2	
�2	+	�
�2
�2)	��,�	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	
; 	
�	�	=	−	�	(
??????2�	
??????�2	+	�
??????2�	
??????�2)	=	�	∑	∑	??????2(
�2
�2+	�
�	2	
�2)	��,�	���	
�??????�
�	���	
�??????�
�	
∞
�=1	
∞
�=1	
; 	
�	��	=	??????	=	−	(1	−	�)	
??????2�	
??????�??????�	=	−	�	(1	−	�)∑	∑	
��??????	2	
��	��,�	�??????�	
�??????�
�	�??????�	
�??????�
�	
∞
�=1	
∞
�=1	
; 	
 	Ko’ndalang kuchlarni hisoblashda quyidagi ifodalarga kelamiz:	 	
��	=	
??????�	�	
??????�	+	
??????�	��	
??????�	=	−	�	∑	∑	(
�	3??????3	
�3	+	
�	3�3??????3	
��	2	)	��,�	���	
�??????�
�	�??????�	
�??????�
�	
∞
�=1	
∞
�=1	
 	
��	=	
??????�	�	
??????�	+	
??????�	��	
??????�	=	−	�	∑	∑	(
��	2??????3	
�2�	+	
�	3??????3	
�3	)	��,�	���	
�??????�
�	�??????�	
�??????�
�	.	
∞
�=1	
∞
�=1	
 	
 	
 	  Mustaqil ishlash uchun topshiriqlar	 	
Jadvalda berilgan variantlarga mos qobiqning 	deformasiyalanganlik	- 	
kuchlanganlik holatini aniqlang	 	
 	
№	 	�(�,�) 	� 	� 	� 	ℎ 	�	 	� 	Material 
nomi	 	
Mexanik 	
xarakteristikala	
ri 	
�,  	
10	11	 ��	 	
� 	
1 	��	 	0.05	 	1 	1 	0.01	 	1 	1 	Beton	 	0.2 	0.17	 	
2 	(1−	�)(1−	�) 	0.02	 	1/2 	1/2 	0.01	 	1 	1 	Miss 	 	1 	0.3 	
3 	2�+	3 	0.08	 	1 	2 	0.01	 	1 	1 	Cho’yan 	 	1.5 	0.25	 	
4 	2�+	1 	0.01	 	2 	2 	0.01	 	1 	2 	Po’lat 	 	2 	0.34	 	
5 	3�−	2 	0.06	 	2 	1 	0.02	 	1 	1 	Alyumin	  	0.8 	0.35	 	
6 	(1−	�)� 	0.05	 	1 	1 	0.03	 	1 	1 	Beton 	 	0.2 	0.17	 	
7 	(1−	�)� 	0.04	 	3/2 	3/2 	0.02	 	1 	1 	Alyumin	 	0.8 	0.35	 	
8 	(�+	2)(�+	1) 	0.03	 	1/2 	1/2 	0.01	 	1 	1 	Alyumin	 	0.8 	0.35	 	
9 	��	+	1 	0.06	 	1 	1 	0.06	 	1 	1 	Po’lat	 	2 	0.34	 	
10	 	3+	��	 	0.07	 	2 	1 	0.05	 	2 	1 	Cho’yan 	 	1.5 	0.25	 	
11	 	5−	2��	 	0.08	 	2 	2 	0.05	 	1 	1 	Miss 	 	1 	0.3 	
12	 	�+	5� 	0.1 	2 	2 	0.05	 	1 	1 	Alyumin	 	0.8 	0.35	 	
13	 	2−	� 	0.02	 	1/2 	1/2 	0.01	 	2 	2 	Cho’yan 	 	1.5 	0.25	 	
14	 	4+	3� 	0.08	 	1 	2 	0.02	 	1 	1 	Po’lat 	 	2 	0.34	 	
15	 	6−	7� 	0.05	 	2 	1 	0.02	 	1 	1 	Miss 	 	1 	0.3 	
16	 	�+	3� 	0.1 	2 	2 	0.06	 	1 	1 	Beton 	 	0.2 	0.17	 	
17	 	5(�+	�) 	0.1 	2 	2 	0.1 	1 	1 	Alyumin	 	0.8 	0.35	 	
18	 	(3−	�)(�+	2) 	0.05	 	1 	1 	0.01	 	1 	1 	Po’lat 	 	2 	0.34	 	
19	 	(�−	5)(�+	2) 	0.1 	2 	2 	0.07	 	1 	1 	Alyumin	 	0.8 	0.35	 	
20	 	6��	+	4 	0.05	 	2 	1 	0.02	 	1 	1 	Po’lat 	 	2 	0.34	 	
21	 	3�+	2��	 	0.04	 	3/2 	3/2 	0.01	 	1 	1 	Cho’yan 	 	1.5 	0.25	 	
22	 	��	+	4� 	0.1 	2 	2 	0.05	 	1 	1 	Miss 	 	1 	0.3 	
23	 	8�+	5 	0.03	 	4/2 	1/2 	0.01	 	1 	2 	Alyumin	 	0.8 	0.35	 	
24	 	7−	2� 	0.05	 	1 	2 	0.01	 	2 	1 	Cho’yan 	 	1.5 	0.25	 	
25	 	4+	��	 	0.05	 	2 	2 	0.02	 	1 	2 	Po’lat 	 	2 	0.34	 	
26	 	(3+	�)(�ғ2	) 	0.03	 	3/2 	3/2 	0.01	 	1 	1 	Cho’yan 	 	1.5 	0.25	 	
27	 	(�+	2)(�+	1) 	0.02	 	2 	2 	0.05	 	1 	1 	Miss 	 	1 	0.3 	
28	 	2��	+	6 	0.05	 	4/2 	1/2 	0.01	 	1 	2 	Alyumin	 	0.8 	0.35	 	
29	 	8+	2��	 	0.06	 	1 	2 	0.01	 	2 	1 	Cho’yan 	 	1.5 	0.25	 	
30	 	7+	2��	 	0.08	 	2 	2 	0.02	 	1 	2 	Po’lat 	 	2 	0.34	 	
 	
 	  A	dabiyotlar ro’yxati	 	
 	
1.	 Александров  А.  В.,  Потапов  В.  Д.  Основы  теории  упругости  и 
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