//example 10.4 //check section for: //Stability of d/s slope against steady seepage //Sloughing of u/s slope against sudden drawdown //Stability of the foundation against shear //Seepage through body of dam clc;funcprot(0); //given //Dimensions H=20; //Heigth of dam Bt=6; //top width of dam s1=4; //u/s slope s2=3; //d/s slope fb=2; //free board //Properties of materials of dam gamma_d=17.27; //dry density wc=0.15; //optimum water content gamma_s=21.19; //saturated density gamma_w=9.81; //unit weigth of water wavg=19.62; //average unit weigth under seepage theta=26; //average angle of internal friction(degree) co=19.13; //average cohesion K=5D-4; //coefficient of permeability //properties of foundation materials gamma_f=17.27; //average unit weigth cof=47.87; //average cohesion fi=8; //average angle internal friction t=6; //thickness of clay FOSp=1.5; //permissible factor of safety of slope PS=8D-6; //permissible seepage //(a) Stability of d/s slope against steady seepage An=302.4; //area of N diagram At=91.2; //area of T diagram Au=98.4; //area of U diagram Le=60; //length of arc SumN=An*gamma_s; SumT=At*gamma_s; SumU=Au*gamma_w; F=((Le*co)+(SumN-SumU)*tand(theta))/SumT; F=round(F*100)/100; mprintf("Part(a):") mprintf("\nFactor of safety for slope=%f.",F); mprintf("\nSafe"); //(b) Sloughing of u/s slope against sudden drawdown h1=15; b=80; P=gamma_s*H^2*tand(45-(theta/2))^2/2+gamma_w*h1^2/2; sav=P/b; smax=2*sav; Ne=(gamma_s-gamma_w)*b*H/2; R=Ne*tand(theta)+co*b; fs=R/P; fs=round(fs*100)/100; mprintf("\n\nPart(b):") mprintf("\nFactor of safety w.r.t average shear=%f.",fs); mprintf("\nSafe"); sr=0.6*H*(gamma_s-gamma_w)*tand(theta)+co; FS=sr/smax; FS=round(FS*100)/100; mprintf("\n\nFactor of safety w.r.t maximum shear=%f.",FS); mprintf("\nSafe"); //(c) Stability of the foundation against shear h1=26; h2=6; gamma_m=(wavg*(h1-h2)+gamma_f*h2)/h1; l=(gamma_m*h1*tand(fi)+cof)/(gamma_m*h1); fi1=atand(l); P=(h1^2-h2^2)/2*gamma_m*tand(45-(fi1/2))^2; sav=P/b; smax=2*sav; s1=cof+gamma_f*h2*tand(fi); s2=cof+gamma_m*h1*tand(fi); as=(s1+s2)/2; fs=as/sav; fs=round(fs*100)/100; mprintf("\n\nPart(c):") mprintf("\nFactor of safety w.r.t overall shear=%f.",fs); mprintf("\nSafe"); gamma_av=(wavg*0.6*H+gamma_f*h2)/((0.6*H)+h2); s=cof+gamma_av*0.6*H*tand(fi); fs=s/smax; fs=round(fs*100)/100; mprintf("\n\nFactor of safety w.r.t overall shear=%f.",fs); mprintf("\nUnsafe"); //(d) Seepage through body of dam s=2; //measured q=K*s*100000/100; mprintf("\n\nPart(d):") mprintf("\n Seepage through body of dam=%fD-5 cumecs/m length of dam",q);