Single option$(2\text{'}$ per question$)$

The reason why concrete and steel bars can cooperate well excludes which option? A they have a strong bond to transmit force

B they have approximate thermal expansion coefficients

C the surrounding concrete can protect the steel bars from corrosion

D they have similar compressive strength

The category of permanent load and variable is based on $()$

A load variability with time

B load variability with location

$C$ load response of structure

$D$ load acting period

$3.$ In general, the relationship of the three coefficients is $()$

A $1>{}_c>{}_f>{}_q$

${}_c>{}_f>{}_q>1$

C $1>{}_f>{}_c>{}_q$

D $1>{}_f>{}_q>{}_c$

$4.$ Which following option provides horizontal load $()$

A live load on roof $B$ dead weight of beam $C$ crane load $D$ snow load

$5.$ The factors affecting wind load acting on a structure exclude which option $()$

A structure height B structure shape factor C terrain factor D temperature

$6.$ The design reference period of the building structure is of $()$ years.

A $5$

B $25$

C $50$

D $100$

$7.$ Which following factor is related to the design working life $()$

A $L$

$0,$ C $c$

D $q$

$8.$ Which following option doesn't belong to ultimate limit state cases $().$

A a structure failure due to inadequate material strength

$B$ a structure overturns due to unequilibrium soil pressure

C a structure has an excessive deformation which affects its serviceability

D a column bulks

$9.$ The representative value of the permanent load is $()$

A characteristic value $B$ combination value $C$ frequent value $D$ quasi permanent value

$10.$ The partial factor of a variable load which has a favorable effect on the load effect should adopt $()$

A $1\mathrm{.}2$

B $1\mathrm{.}4$

C $1\mathrm{.}3$

D $0$

$11.$ The $C30$ means $()$

A fcu, $k=30$MPa

B fcu $=30$MPa

$Cfc=30$MPa

D ftk $=30$MPa

$12.$ Which following option is not the consequences of concrete creep. $()$

A re$-$distribution of stress $B$ lose of prestressed force

C increasement of deformation

D erosion of steel bar

$13.$ The consequence of confining pressure on concrete excludes $()$

A better ductility $B$ higher strength $C$ higher peak strain $D$ identical peaks strain

The yield strength of soft steel adopts the value of $()$

A the ultimate strength B $0\mathrm{.}85$ times of the ultimate strength

$C$ the lower yield strength

$D$ the higher yield strength

$15.$ The design value of compressive strength of HRB$500$ is of $()$

A $435$MPa

B $410$MPa

C $500$MPa

D $510$MPa

II$.$ Briefly answer $(20\text{'})$

Provide a concise explanation for the stress re$-$distribution phenomenon induced by creep in a reinforced concrete column.

III. Calculation

There is a room whose beam and column layout presented in the figure below. The reinforced concrete slab has a thickness of $100mm.$ The secondary beam within the room possesses a cross section with dimensions $bxh=200mm400mm.$ It is required to calculate the characteristic value of the permanent load transmitted from the secondary beam to the main beam at point A$.(25\text{'})$

The beam under consideration is a simply supported rectangular cross$-$section beam with a safety classification of $11.$ Its cross$-$sectional dimensions are $bxh=200mm400mm.$ The calculated length is $l_0=5\mathrm{.}00m($used to calculate the bending moment$),$ while the net length is $l_n=4\mathrm{.}86m($used to calculate the shear force$).$ Two linear loads act on the beam: a permanent load with a characteristic value of $10k\frac{N}{m}($excluding self$-$weight$)$ and a variable load with a characteristic value of $7k\frac{N}{m}.$ Additionally, there is a variable point force applied at the mid$-$span with a characteristic value of $20kN.$ calculate the basic combination for obtaining maximum bending moment at midspan and maximum shear force at the support edge. $($note: the design working life is $100$ year, and the combination coefficient is $0\mathrm{.}7)$