What is the total male-female ratio in Chang 'an University and the male-female ratio in the Department of Traffic Engineering? Total: 3/ 1 Flow:11.
What is the ratio of male to female in the chemistry department of East China Normal University? /3:7, which is the ratio of male to female in normal universities as a whole.
What is the ratio of boys to girls in the school? Let's just say what the male-female ratio is in this school. For example, there are more boys in engineering schools and more girls in art schools, as well as foreign languages and economics. It's different from school.
What is the ratio of male to female in kindergarten teachers? Capable people can't find good jobs anywhere. On the contrary, young people who lack work experience may encounter many difficulties and setbacks wherever they go without correct career planning, good job-hunting motivation and mature job-hunting skills. So I'll give you some advice in the process of job hunting: I personally emphasize that no matter whether you study as a major or look for a job, there is a principle, that is, what is hot, learn from the chef. Chefs are particularly popular now.
What's the ratio of male to female in the Department of Mathematics of Guangxi Normal University, brother? You have found the right person. 5: 1
What is the buried depth ratio of steel sheet piles? Determine the type of steel sheet pile in deep foundation pit: 6-9m steel sheet pile is used for excavation over 3m.
If the deep foundation pit is more than 5m, it needs to be supported by stages. If there is no condition, it can be anchored and supported.
In the model, Larsen steel sheet pile has good strength and ideal water-stopping effect.
SP-III No.3 Pile 9m, 12m
SP-IV No.4 Pile 12m, 15m
Sp-ivw No.6 pile 18m, 2 1m
Calculation sheet of steel sheet pile support
The excavation depth at pile number 2c0+390 and the excavation width at 4C0+00 1.5 shall prevail (the maximum excavation depth and width of this project).
Design data
1 pile top elevation H 1: 4. 100 m
Construction water level H2: 3.000m.
2 Ground elevation H0: 4.350m.
Elevation of excavation bottom H3:-3.400m.
Excavation depth h: 7.7500m.
3. Soil bulk density plus total average value γ 1: 18.3kn/m3.
The floating bulk density of soil is γ′:10.0kn/m3.
The total average value of internal friction angle Ф: 20.10.
4 uniformly distributed load q: 20.0kn/m2
5 excavation length a = 20.0m, and excavation width b = 9.0m
Second, the external force calculation
1 Earth pressure intensity and pressure distribution diagram acting on sheet piles
ka = tg2(45-φ/2)= tg2(45-20. 10/2)= 0.49
KP = tg2(45+φ/2)= tg2(45+20. 10/2)= 2.05
The height h of that fil soil is converted by the uniformly distribute load on the outer side of the sheet pile,
h = q/r = 20.0/ 18.3 = 1.09m
Earth pressure intensity above pile top Pa 1
pa 1 = r×(h+0.25)Ka = 18.3×( 1.09+0.25)×0.49 = 12.0 kn/m2
Water level earth pressure intensity Pa2
Pa2=r×(h+4.35 -3.00 )Ka
= 18.3×( 1.09+4.35-3.00)×0.49 = 2 1.8 kn/m2
Earth pressure intensity Pa3 on excavation face
pa3 =[r×(h+4.35-3.00)+(r-rw)(3.00
+3.40)}Ka
=[ 18.3×( 1.09+4.35 -3.00 )+( 18.3- 10) ×(3.00
+3.40)]
× 0.49 = 47.8kN/m2
Water pressure on excavation surface (after cofferdam pumping) Pa4:
pa4 =γ(3.00+3.40)= 10×(3.00+3.40)= 64.0 kn/m2
3. Determine the number and spacing of internal supports.
Type Ⅲ steel sheet piles supported on each floor are determined according to the equal bending distance arrangement.
The maximum bending distance that can be endured determines the maximum allowable span h of the cantilever end of the sheet pile top;
The bending section system WZ0 = 0.00 1.350m3, and the reduction coefficient β=0.7.
The value wz = β wz0 = 0.00135× 0.7 = 0.000945m3.
Allowable tensile strength [σ] = 200000.0kpa
According to the formula σ=M/Wz:
Maximum bending moment m0 = wz× [σ] =189.0kn * m.
1 Assuming that the top support position is as high as the water level, the bending moment at the fulcrum is
m ' = pa 1 *(h 1-H2)2/2+(Pa2-Pa2)(h 1-H2)2/6 = 9.2 kn * m & lt； M0= 189.0KN*m
Therefore, the support point can be set below the water surface.
2 According to the above judgment, the maximum allowable span h0 is calculated according to the following formula.
M0 = pa 1h 02/2+γka(h 1-H2)2[h02(h 1-H2)/3]/2+(Pa2-pa 1)[h0-(h 1-H2)]2/2+(γw+γ')[h0-(h 1-H2)]3/6
Substitution value:
189.0 = 6.0×h02+4.47× 1.2 1(h0-0.733)+4.9 16(h0- 1. 10)2+3.333(h0- 1. 10)3
Finishing:
3.333 h03+5.92 1h 02+6.692 h0- 19 1.454 = 0.000
To solve this equation:
h0=3.20 1m
Each bearing is arranged according to equal bending moment, then:
h 1 = 1. 1 1h 0 = 3.553m
H2 = 0.88 h0 = 2.8 17m H3 = 0.77 h0 = 2.465m H4 = 0.70 h0 = 2.24 1m
h5=0.65h0=2.08 1m
h6 = 0.6 1h 0 = 2.8 17m H7 = 0.58 h0 = 1.857m h8 = 0.55 h0 = 1.76 1m
Therefore, at least two layers of support are needed.
As shown in the figure, determine the support position according to the actual situation.
h0 = 2.000m h 1 = 3.000m H2 = 2.500m
Four internal support reaction forces
The reaction force of each internal support is approximately calculated by 1/2 sharing method.
q 1 = p 1(h0+h 1)/2 = {γka(h+(h 1-H2)+(γ'+γw)ka[(h0-(h 1-H2)]}(h0+h 1)/2
= 7 1.0 kn/m
Q2 = p2(h 1+h {γka *(h+(h 1-H2)+(γ'+γw)ka[(h0+h 1-(h 1-H2)])(h 1+H2)/2
= 158.7 kn/m
5. Buried depth and total pile length of steel sheet pile:
Calculation of pile depth by shield method
Through the formula γHKa(hi+t)=γ(Kp-Ka)t2
Finishing:
(Kp-Ka)t2-Hkat-Hkahi=0
The solution is t = = 4.837 m.
Therefore, the total length l = h0+h1+H2+... hi+t =12.337m.
The length of steel sheet pile is14.0m, and the actual buried depth is t = 6.500m
Six foundation pit bottom uplift checking calculation
Nq=eπtgφtg2(45+φ/2)=6.463
NC =(Nq- 1)/TGφ= 14.929
The weighted natural bulk density of each layer of soil outside the pit is γ1=18.3m3.
The weighted natural bulk density of each layer of soil in the pit is γ 2 =18.2m3.
Soil cohesion c = 5.0kpa
Therefore, the anti-floating safety factor
ks =(γ2 tnq+cNc)/(γ 1(H+T)+q)= 3.03 & gt； 1.3 meets the requirements.
Checking calculation of piping at the bottom of foundation pit
KL=γ'T/γwh=2γ'/γwhw
= 2.03 & gt 1.5 meets the requirements.
Seepage calculation at the bottom of dam pit
According to the design geological data, the comprehensive permeability coefficient of soil is taken as k = 0.080m/d.
Excavation area of foundation pit A=a*b = 180.
Q=KAi=
KAhw/(hw+2T)
= 4.75 m3/day
Stress Calculation of Jiuwei Purlin (20m)
1 supporting force: r = n/4 = Q2 * a/4 = 793.42kn.
2 Support arrangement is shown on the right.
3 purlin bending moment
Braces are arranged at equal intervals, as shown in the following figure:
L = a/4 = 5.000
Because the integrity of the installation node is usually not easy to ensure, so according to the simply supported beam calculation:
Mmax=q2l2/8=495.9KN*m
It is planned to select hollow square steel (400*400* 14).
Bending section system Wz=0.00252 1m3
Allowable tensile strength [σ] = 200000.0kpa
The maximum bending moment that square steel can bear is m = wz [σ] = 504.2kn * m > Mmax=495.9KN*m meets the requirements.
Force calculation of ten support rods
It is proposed to select hollow square steel (250*250*8).
Calculated length l0=8.2m, bearing surface A=7520mm2, moment of inertia I=72290000mm4, bulk density γ=78.5KN/m3, and bending section system Wz=578000mm3.
According to Table 5. 1.2- 1 in Code for Design of Steel Structures, it is a Class B member.
Initial eccentricity LP of steel support = l0/500 = 0.016m.
Find the slenderness ratio λ:
I = = 97mm
λ=l0/i=85 because the cross section is axisymmetric. Check the profit and loss stability coefficient φ=0.648 in Schedule C of the specification.
Therefore σ1= n/a/φ = r/a/φ =15811.1kpa.
[σ]= 200000.0 kPa
Dead weight bending moment m = γ Al2/8 = 5.11kn * m.
Therefore, σ 2 = m/wz = 8835.0kpa
Then σ = σ 1+σ 2 = 166946.0.
Eleven structural requirements
1 In order to prevent water leakage at the joint, butter, asphalt or other sealing and water-stopping materials should be embedded in the lock mouth before pile sinking, and seepage-proof grouting can be carried out outside the pit or another water-retaining curtain can be built after pile sinking if necessary.
2 The supporting steel sheet piles at the corner of foundation pit should be made into corresponding special-shaped corner steel sheet piles according to the plane shape of the corner, and the corner piles and positioning piles should be lengthened by1m..
What is the ratio of male to female who study veterinary medicine? Animal medicine is a traditional agricultural specialty, and there are always more boys than girls in animal medical college. There is a simple reason. When it comes to animal medicine, people often think of pigs, cows and sheep. These animals are masculine and hard, which are more suitable for boys to practice. The economy is developing, the society is progressing, and the old major is full of youth. In recent years, due to the prevalence of serious diseases such as avian influenza and mad cow disease, the importance of veterinarians has attracted the attention of * * and the public; At the same time, with the improvement of people's living standards, pets have become a member of many families, especially in large and medium-sized cities. As a result, veterinarians, animal doctors and pet doctors are an enviable industry, which is inseparable from modern society. Some experts have long predicted that "human doctors, veterinarians and botanists will be tripartite confrontation." The image of Dr. Niu Ma, a traditional veterinarian, is quietly changing, gradually becoming a high-income industry, and animal medicine is gradually becoming a hot specialty. In 2000, the proportion of male and female freshmen in Animal Medical College reached 1: 1, and the proportion of female students increased slowly year by year. This year, the ratio of girls to boys exceeded 2: 1, which is a special case in the enrollment history of animal medical college.
It seems that there are more women in college, but not many women actually engage in veterinary work after graduation, and many women have changed careers, which may be the reason why veterinarians are actually tired and dirty. . . There are fewer women selling veterinary drugs, which may be mainly because live men running errands in veterinary drug sales are more suitable. . . However, women take more veterinary postgraduate exams.