SNe Ia+OHD+GW                          SNe Ia+OHD+Planck-2015+GW                    
  ---------------- -------------------------------------------- -------------------------------------------- -- -- -- --
   $\chi^2_{min}$                   $579.444$                                    $579.455$                            
   $\Omega_{m0}$    $0.2660^{+0.0553+0.0927}_{-0.0524-0.0858}$   $0.2684^{+0.0552+0.0903}_{-0.0522-0.0864}$           
   $\Omega_{r_c}$   $0.1902^{+0.0221+0.0369}_{-0.0209-0.0346}$   $0.1912^{+0.0229+0.0379}_{-0.0203-0.0347}$           

  : Minimum values of the derived $\chi^2$; corresponding $1\sigma$, $2\sigma$, and $3\sigma$ confidence intervals; and the best-fitting values of the model parameter pair ($\Omega_{m0}$, $\Omega_{r_c}$) in the DGP braneworld scenario obtained by using different kinds of constraints: SNe Ia, OHD, Planck-2015, and GW.[]{data-label="tab1"}

In the present work, we utilize the Union 2.1 data sets for numerical analysis; these are composed of 580 SNe Ia data points covering the redshift range \[0.015, 1.4\]. To exhibit the standard $\chi^2$ statistical estimates, the theoretical distance modulus is defined as $\mu_{th}(z_i)=m-M=5\log_{10}d_L(z_i)+25$, where $m$ is the apparent magnitude, $M$ is the absolute magnitude, and $d_L(z_i)$ is the luminosity distance at a given redshift $z_i$ in units of Mpc. The luminosity distance is defined as $d_L(z_i)=(1+z_i)\int^{z_i}_0\frac{dz'}{E(z';\theta)}$, where $\theta$ represents a set of model parameters. Then, the corresponding $\chi^2$ for the SNe Ia observations is written as $\chi^2_{SN}=\sum^{580}_{i=1}[\frac{\mu_{obs}(z_i)-\mu_{th}(z_i;\theta)}{\sigma_i}]^2$, where $\mu_{obs}$ is the observed value of the distance modulus and $\sigma_i$ is the corresponding 1$\sigma$ statistical error at a given redshift $z_i$. We use the latest OHD set consisting of 36 data points, which are obtained from model-independent 